Posted by: TJ | November 7, 2009

A Guide Around Mazda Raceway Laguna Seca

Since a lot of our races will be held on Laguna Seca I figured a track guide may be useful for some of you.

Track Map

Image:LagunaSecaOverview.gif


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Turn 1

(I’m not a pro, probably not even very good, but I’ve been fortunate enough to do about 100 laps of Laguna Seca in an S2000. Speeds and gears for a stock S2000… Adjust all speeds gears for the appropriate car.)

Although it doesn’t seem like much of a turn but is possibly the scariest. Since the approact to T1 is uphill and the turn itself is on the crest, this can leave the rear end light at high speed on fast cars with low downforce.

For now just picture yourself winding out full throttle at 90-95 mph in 3rd or just having shifted to 4th and hitting 100-105 having just cleared the Start / Finish hitting a speed of 90-100 miles an hour as you approach the Andretti Hairpin.

This is a full throttle corner that has poor approach visibility. That’s the challenge. A ‘chicken lift’ rising over the hill means less pucker and a lot of lost time. With the lift your approach to Corner 2 is about 90-95 instead of 100-105 mph. My first visit to Laguna I lifted for about 30 consecutive laps before getting up the gumption to go full out. A big smile followed my 31st attempt.

Exiting, you should be aiming for the #1 or #2 Brake Marker (BM) of Corner 2.

Turn 2 “The Andretti Hairpin”

“The Andretti Hairpin” 190 deg left hand hairpin – 45mph 3rd gear or 2nd if challenged:

Corner 2 is the first corner you hit if you enter right after exiting the pits the way the Champ Cars do. Motorbikes use the FIA entrance which enters the track after corner 2. I’ve used both and prefer the FIA entrance for safety (this enters the track right *after* the hairpin.

Single Apex Method (Novice): Usually when approaching this corner I’m aiming for the #2 or #1 Brake Marker (BM) and hard on the brakes at or just before #4. You need all of the braking you can get since you’re going about 100-110mph if you have done Corner 1 correctly. You heel and toe downshift from 4 to 3 (or 2) but be sure to get speed down below 50 before releasing if in 2nd or you will have a big problem. The key (on the single apex approach) to this corner is remember to stay outside until at nearly halfway around the corner. By this time you should have come in from the right about 1/3 of the way. Remember to hit a late apex here since an apex too early is how my friend made his S2000 a sub-compact. Use all the track and the rumble strip to “track out”. Come back in to the left slightly and straighten and THEN turn toward the BM 4. Get over left and then turn along the outside of the track. A slight right kink will force you to turn right slightly… brake in a straight line between 2 and 1 and turn at one. Stay in 3rd unless you are heavily challenged.

Double Apex Method: If you are trying for higher times you might try the double apex approach to Corner 2. Use the same approach to the corner but instead of braking hard at brake marker (BM) 4 to BM 1 turn in to the corner on the left and brake late (BM2?) which takes you right at the apex to the outside of the hairpin. then turn in and hit the exact same apex at before.

Turn 3

Corner 3 right hander – 50-55mph 3rd gear or 2nd if challenged:

Corner 3 approach is as above and in 2nd or 3rd you hit a moderately late apex and track out. Turn in is BM 1 (this is the standard on this track) and use the rumble strip if necessary (this is optimal). You are now on the far left of the track… stay there going under the big tire.

If you have entered T3 at the proper entry speed and hit your apex, you should gain good momentum to carry you through T4 and up to T5 where the uphill really begins.

Turn 4

Corner 4 right hander – 70mph 3rd gear:

Corner 4 is probably my favourite. Hard on the gas to BM 2. Punch the brakes for a spit second to slow slightly and turn in early… about 2/3 the way between BM 2 and 1 (like BM 1.3). Don’t shift. You’ll be on the power still in 3rd as you turn and hit a surprising EARLY apex. Weird, I know, but it works. You are going to take this very fast and will need to get 2 tires on the left hand rumble strip. This sets you up nicely for a sweeping kink with no name. I call it “the sweeping kink with no name”.

Run through this at full speed and if I’m getting the hang of the track I’ll be shifting into 4th and hitting nearly 105 before hitting the brakes for 6.

Turn 5

Corner 5 left hander – 50-55mph 3rd gear:

The biggest challenge for me in Corner 5 is the inevitable downshift to 3rd. This is a pretty fast corner so getting the shift completed without upsetting the car is tricky. Other than that… textbook. Brake between 4 and 2 turn in at 1, moderately late apex and on the gas to the right outside of the track to set up for 6.

Due to the slight kink prior to the bridge preceding the turn, T5 can be deceiving. Watch your markers and brake earlier than you think in order to exit this corner quickly and safely.

Turn 6

Corner 6 left hander – 70-75mph 3rd gear:

I love Corner 6 for its high speed and the cool little gutter on the apex (left side). You don’t brake much in the approach… say BM 3 to 2. You will take this uphill lefthander VERY fast. Maybe 70-75mph. If you can hit a medium apex and get two tires in the “gutter” it will swing you nicely around the corner and zoom up the hill. The temptation in a well executed corner is to NOT track out. WRONG! Track out using the rumble on the right to set up perfectly for the uphill climb to the “little kink”. By doing this you have just straightened the entire climb to Corner 7 and probably gone as quickly through Corner 6 as you can.

T6 is another deceptive corner. You can enter this corner a little faster if you can nail it correctly.

“The Rahal Straight”

This is a long uphill straight that actually has a little kink going up the hill that’s hard to see on the map. The kink is a left hander – full throttle 3rd gear:

Here I’d like to describe an important feature of the track. There is a slight “little kink” in the track between corners 6 and 7. It is right after the bridge (or is it a sign?) and kinks to the left. You should aim for the spot one third to the right of the left side of the sign ( If this is the sign, aim for the asterisk |…..*……….| ) This will have you run OVER the rumble strip and completely straighten the kink. You will now be approaching Corner 7 perfectly.

Turn 7

Corner 7 right hander – 50-55mph 3rd gear:

When you are through the “little kink” as described above you will approach Corner 7. This is barely a corner at all but is super important as a setup for the Corkscrew. Just before Corner 7 the up hill approach steepens abruptly. There is typically a bunch of rubber laid down on the track here. The beginning of this rubber is my start braking mark. Nebulous I know but that’s how I do it.

The track attitude will level off at this kink, leading blindly right into the corkscrew (T8). The fastest times will require careful braking and bravery. As you crest this area of the track watch where your car is pointed as it may go light.

I take this corner differently than I did the first time out at LS and now brake hard setting up for seven. Let off and turn long the outside (right side of the track and STAY to the right. I.e. do not track out. I then hit the accelerator a second and brake again for the Corkscrew.

Turn 8 & 8a “The Corkscrew”

Corner 8A &8B “the Corkscrew” left right “S” curve – 50mph then 60mph 3rd gear or 2nd through 8A and short shift to 3 on the “straight” part:

Here it is. What everyone is waiting for. Corners 8A and 8B are the Corkscrew. The key to the Corkscrew is to straighten between A and B. The natural inclination is to use an “S”… don’t. Turn through Corner 8A with a moderately late apex and then straighten for a split second aiming for the oak… then turn to a medium to late apex on 8B and use all the track. Then aim for the last oak on the left to brake straight and set up for the dreaded Rainey.

Careful modulation of the throttle will keep gravel in this famous turn from spinning your car. After the sharp downhill your suspension will load up allowing you to feed in the power prior to Rainey Curve (T9).

Corner Nine “The Rainey Curve”

Corner 9 “The Rainey Curve” left hand sweeper – 65mph 3rd gear:

Pointing straight at the last oak get on the brakes for about 100 feet. Then let off and begin the turn. Easy does it on this corner carving out a long sweeper. Hit a VERY late apex on the Rainey and run off using all the track on the right to “track out”.

When I drove the track there was a very hazardous concrete gutter on the right side of the track as you come out of the corner. This is exactly where you’d want to track out but if you hit it this became a bit problem. In 2006 the track was redone and happily the gutter was removed.

Corner Ten

Corner 10 right hander – 60-65mph 3rd gear:

Full bore on aiming at the BM#1 for corner 1 and hard brake between 3 and 2 using the BM#1 as the turn in point. hard on the gas here just before the apex. This is surprisingly high speed and you get a lot of room on the left to track out… but you need it.

Corner Eleven

Corner 11 110degree right hander – 35-40mph 2nd gear:

You only get a little while to accelerate because #11 is a b*tch. Brake hard between 4 and 1 and downshift to 2nd. Late apex on this corner OR ELSE!. Track out to the right but geez watch out. That wall is made of concrete.

Start Finish Straight

Start/Finish Straight 2nd to 3rd to 4th 90-95 at the S/F line:

Stay right on the straight ’til about halfway down to the bridge. Then aim for the “AZ” in “MAZDA” This helps straighten out the kink and set up for Corner 1. Right at the bridge is where you’ll hit about 90 and shift to 4th. I think next time I’m aiming for the “Z” to keep me more to the right for Corner 1; driving the kink down the middle and turning in to the left to straighten Corner 1 instead.

Pos Make / Model Time Speed (km/h) Year Power (hp) / Weight (kg) Driven by
1. Devon GTX 1:35.075 136 ´ 659 / - DMW
2. Dodge Viper SRT-10 ACR 1:35.117 136 ´08 600 / 1536 Motor Trend
3. Chevrolet Corvette ZR1 1:35.8 135 ´08 647 / 1530 Motortrend
4. Porsche 997 GT3 1:39.517 130 ´06 415 / 1395 Motortrend
5. Nissan GT-R 1:39.62 130 ´08 479 / 1740 Edmunds
6. Porsche 997 Turbo 1:39.89 130 ´06 480 / 1585 Timed by Edmunds.com
7. Mercedes SLS AMG 1:40.74 129 ´10 571 / 1620 Bern Schneider
8. Audi R8 1:40.8 129 ´06 420 / 1560 Motor Trend
9. Chevrolet Corvette Z06 1:40.9 129 ´05 513 / 1437.3 Motor Trend
10. BMW M3 (E92) 1:42.964 126 ´07 420 / 1619 Motor Trend
11. Porsche Cayman S(facelift) PDK 1:43.0 126 ´08 320 / 1375 Motor Trend
12. Cadillac CTS-V 1:43.9 125 ´09 564 / 1955 Motortrend
13. Shelby GT500 1:44.3 124 ´10 547 / 1767 Motortrend
14. Shelby GT500 1:44.716 124 ´06 507 / 1807 Motor Trend
15. Porsche 997 Carrera (2008 facelift) 1:45.0 123 ´08 345 / 1415 Car and Driver
16. Chevrolet Camaro SS 2010 1:45.7 123 ´10 432 / 1750 Motor Trend
17. Lotus Exige 240R 1:45.818 123 ´05 247 / 941 Motortrend
18. Toyota Supra RZ 1:45.87 122 ´94 284 / 1640 Kurosawa Motoharu
19. BMW 135i Coupe (E82) 1:46.0 122 ´07 306 / 1485 Motortrend
20. Nissan Nismo 370Z 1:46.5 122 ´09 355 / 1500 Motortrend
21. Porsche Cayman S 1:47.577 121 ´05 295 / 1406 Motortrend
22. Mitsubishi Lancer Evo X MR 1:47.713 120 ´08 295 / 1585 MotorTrend
23. Chevrolet Cobalt SS/TC 1:47.751 120 ´08 260 / 1352 Motor Trend
24. Mitsubishi Lancer EVO IX 1:47.926 120 ´05 290 / 1482 Motortrend
25. BMW 335i Coupe 1:49.038 119 ´06 306 / 1610 Motortrend
26. Porsche 997 Carrera S 1:50.0 118 ´04 355 / 1420 Motortrend
27. Mazda 3 MPS 1:50.375 117 ´06 260 / 1485 Motortrend
28. Mazda RX-8 1:50.418 117 ´02 231 / 1379 Motor Trend
29. Honda S2000 1:50.738 117 ´99 239 / 1260 Motortrend
30. Mini Mini Cooper S Works GP Kit 1:51.733 116 ´06 218 / 1180 Motortrend
31. Mazda MX-5 Grand Touring 1:52.2 116 ´09 160 / 1165 Motortrend
32. Honda Civic SI 1:54.990 113 ´06 197 / 1330 Motortrend
33. Honda NSX 1:57 111 ´04 280 / 1330 Jeremy Clarkson
Posted by: TJ | November 7, 2009

Forza 3 Suspension Calculator Released

The epic player, Feuerdog, has released a great suspension tuning calculator to get you started in tuning. This really makes tuning a lot easier.

Here is the link to it. Keep in mind this is basically an Excel doc with some fancy formulas. It’s great stuff.

Forza 3 Suspension Calculator

INSTRUCTIONS FOR USE
1. In the yellow fields you will select a drivetype(FF,FR, FA, MR, MA, RR, RA), and enter the vehicles weight(lbs) and front weight distribution. This info is availiable in the upgrade and car selection areas.
FF = Front engine, Front wheel drive.
MR = Mid engine, Rear wheel drive.
RA = Rear engine, All wheel drive.
etc.

2. In the blue fields you will get all of your suspension geometry settings instantly.

3. The orange fields are optional, but will add small compensations into the values to compensate for aerodynamic downforce and differing tire widths. Tire widths are the first three digit number in the tire size located in the tire width upgrade screen. If you do not want to compensate for aero or tires then leave these cells blank.

TUNING NOTES
- The calcs are not tested or designed for dragging or drifting.
- Front tires that are wider than rear tires may result in calc errors.
- The aero and tire compensation calcs are estimates, and untested for use with FM3.
- You can trick the calcs for understeer/oversteer by changing the front weight distribution input.
- Due to limitations in this older set of calcs, some cars will still feel “understeery”.
- I guarantee nothing.
- Always, always, double check your figures and settings. Even a single 1% of difference can have an impact on handling.
- Also keep in mind that some parts that you change in FM3(cooling upgrades for example) and weight reductions will change your weight distribution around. So even something as simple as an engine upgrade can change the weight bias of the chassis.
-Always recalc your suspension after upgrading parts!
- The aero and tire compensation calcs are OPTIONAL. They are very simple modifiers to begin with.
The aero compensations simply add spring stiffness to each axle.
The tire width compensation simply changes the weight bias to compensate for grip.

CALCULATOR NOTES
- The suspension calculators have always had mixed results with the R-classes in previous FMs. I don’t know if FM3 will be the same yet or not. I hope not. With the new blended classification and stiffness modifications the only real hurdle may be aerodynamics.
- The current state of the calcs is actually a little stiffer than I wanted to make them. There are several reasons for this:
1. A limitation in the calcs relating to dampers.
2. Stiffer springs help counter high aerodynamic downforce.
3. The spring strengths are realistically higher in FM3 anyways.
4. Stiffer springs helps limit roll, and therefore keeps camber settings low.


Another version of this calculator that includes metric units of measurement is available from Slave Munky here.

 

Slave Munky Calc FEATURES
- supports both imperial and metric units
- print area enabled so you can print out your setup and make notes
- FM3 suspension dynamics by feuerdog
- tire pressure settings based on curb weight/load on tire
- an all new optional automatic transmission sheet
- intergrated transmission calc with calculated final drive ratio and individual gear ratios.
- full car list with performance figures and prices
- full rim list with weight loss %
- stiff suspension values for the ADVANCED tab for a stiffer suspension and mostly likely faster lap times
- Aerodynamics sheet still under construction

INSTRUCTIONS

To tune any car make sure you are in it and go to:
1.my cars
2.press x (car list)
3.press the LB until you reach the data needed (ex: power rpm, curb weight, redline rpm, etc.)
4.input into sheet
5.if aero parts are installed, write the default vaules into advanced>aero>default downforce.
6.if using the stiff suspension values, make sure you recheck these numbers for any change you make in weight and downforce.

Also check the Forza 3 section here at 360 Maniac for more info on tuning. Good luck and get racin’.

Posted by: TJ | November 7, 2009

The Real Truth About Understeer

If you go to the track, you should read this. Even if you think you know everything there is to know about understeer, you’ll probably learn something.

What exactly is understeer? In purely technical terms, it’s a lack of front tire grip. But what does that actually mean? What causes it? How can you get rid of it mid-corner? How can you avoid it altogether? And most importantly, why is it actually MORE dangerous than oversteer?

First, let’s understand exactly what understeer means. When you enter a corner and the car begins to “push” toward the outside of the turn, you’re experiencing understeer. You’ve dialed in the correct amount of steering input (turned the wheel the correct amount) but the car is turning less than it should.

REASONS FOR UNDERSTEER

So, why does this happen? This happens because your rear tires have more grip than your front tires. When you begin to turn, instead of the front tires gripping on the road, they slide. This can happen for one of three basic reasons:

1) You’ve entered a corner too fast (surprisingly, this isn’t usually the problem!)
2) You’re trying to turn too much (you’ve actually asked the tires to do more than you need them to do)
3) Your brake and/or throttle inputs haven’t loaded the front suspension properly (this is your problem, 95% of the time)

Let’s discuss #3 first, as this is the most common cause of understeer. To understand load transfer, also commonly (and incorrectly) referred to as weight transfer, perform this simple exercise:

Place your hand face-down on the table/desk in front of you. Slide it forward on the table. Your hand slides easily because you have very little load forcing it on the table. Now stand up, and lean on your hand. While leaning on your hand, try to slide it forward. It doesn’t slide. This is because you have a lot of load on your hand. The same exact thing is constantly happening with your tires. When you have load on your tires, they grip. When you don’t, they slide.

Simply put, when you accelerate, load is transfered rearward. When you decelerate, load is transfered forward. Deceleration doesn’t necessarily mean braking, as coasting or even easing off the throttle will cause the vehicle to slow down (decelerate). This is even more dramatic when driving up hill, as the slightest decrease in throttle input causes the car to decelerate significantly.

BRAKE RELEASE

So, we know that understeer is caused by a lack of front grip, and we know that we can increase front grip by transferring load to the front of the car. So as long as we decelerate before every corner, we’ll never understeer ever again! Right? Well, it’s not quite that easy.

The way in which we brake and accelerate, or more importantly, the way in which we release the brakes and roll on the throttle, determines how the load is transfered, how much load is transfered, and most importantly, how much load actually STAYS in the front of the car.

If we brake very hard, a lot of load is sent to the front. However, if we abruptly lift off the brakes and get back on to the throttle, all of that load goes right back to the rear. In fact, when you’re accelerating hard, the front tires have so little load that they’re barely making contact with the ground. Just think about how well your car would steer if you were doing a wheelie through the turn.

So, how can we accelerate through a corner and still maintain a healthy amount of front load and grip? The answer is proper brake release, followed by sensitive throttle input. Ideally, a passenger should not be able to tell when you’ve gotten off the brakes and on to the gas.

To do this, you need to revise your braking strategy. Braking “late” or “diving” in to corners and getting on the power early may seem like the fastest way around the track, but this usually slows people down. There is a way to brake late and get on to the throttle sooner, but it can’t happen until you’ve mastered proper brake release.

To start out, brake 10-20% earlier than you normally would. Try to get all of your braking done well before the corner. At this point, you should feel like you broke too early. You have a quarter to half a second of time, which feels like an eternity, in which you don’t need to be slowing down anymore, but you don’t need to be turning yet. During this “dead space” you focus on one thing, and one thing only: brake release. This is your time to gradually release the brakes and begin to turn in. As you get comfortable with this, you can begin braking where you normally did before, combining this smooth brake release with your turn-in, often referred to as “trail braking.” You then need to follow this up with an equally smooth and gradual application of throttle. Smashing on the gas at this point will ruin all of the work you’ve done up this point with your brake release.

If done correctly, one of two things will happen depending on a variety of factors:

1) The car will be perfectly neutral through the turn and will turn exactly the same amount as you turn the steering wheel.
2) The car will oversteer slightly, turning more than you turn the steering wheel.

No explanation is needed for #1. You’re good to go. Congratulations, for the first time ever, your Subaru isn’t fighting you through a turn.

OVERSTEER AND “ZERO-STEER”

Next, we have situation #2. This is a GOOD situation to be in, do not be afraid! Clearly, hell has frozen over, as your Subaru is oversteering. How could this have happened? The answer is you’ve successfully trail braked to the point that you actually have so much front grip that your car is able to turn more than you asked of it. Depending on how quickly you recognize this behavior, you may be able to experience something we call “zero-steer.”

As soon as the oversteer initiates, you can roll on the power. If you’re quick enough, you’ll barely need to correct your steering input (counter-steer) as your throttle input will send load to the rear, reducing front grip. This reduction of front grip stops the oversteer, and you may end up with “zero-steer” where the steering wheel is in the dead center position and the car is turning around the corner almost by itself. At this point, you’re simply steering with the gas pedal. More gas steers towards the outside of the turn, less gas steers towards the inside of the turn, and maintaining throttle keeps you on your current path. This is not only the fastest way around the corner, it’s also the easiest on your tires. Unfortunately, even for the best of drivers, it’s not something you’ll experience every corner, but it’s sure nice when you do.

Now, assuming you’re not quite quick enough and you catch the oversteer a little late, you’ll need to make a slight counter-steer correction. This is extremely fast, and extremely minor. We’re not drifting, we’re not going around the corner with the steering wheel turned in the opposite direction. Simply reduce your steering input (or even temporarily steer in the opposite direction for a split second) and slowly get on to power. Things will quickly sort themselves out and you’ll be going around the turn with very neutral handling. Continue rolling on the power, but don’t accelerate too much! You’ll just end up with understeer again.

As you unwind the wheel and start exiting the corner, you can accelerate more and more. When the wheel is almost straight, you can fully accelerate. It is for this reason that we want to get the car rotated early. The more turning we do at the beginning of the corner, the less we have to do at the end, which means we spend more time on the gas, and less time steering.

I THINK THAT MIGHT BE A BIT BEYOND MY SKILL LEVEL

If this oversteer / zero-steer situation has you scared, or you don’t feel that you will be able to recognize the oversteer soon enough, there is absolutely no reason that you ever need to be in this situation. The only way for this to happen is by trail braking too much. This means your brake release continued too far in to the beginning of the corner.

To assure that this doesn’t happen to you, simply finish your brake release in a straight line, and start your sensitive application of throttle at turn-in. As you get more and more comfortable, you can try trail braking a little at a time. Do your brake release 1% in to the corner, then 2%, then 5%, etc. Eventually, as you get more confident, you’ll find yourself trail braking the first 10% of most corners. Please, PLEASE, keep in mind that “trail braking” is NOT actual braking. This is simply combining your brake release with your turn-in. If you’re actually doing any kind of real STOPPING during your turn-in, you are asking for trouble!

THAT’S GREAT AND ALL, BUT I SCREWED UP AND THE CAR IS UNDERSTEERING AS USUAL. NOW WHAT?

When you can’t prevent understeer, you can eliminate it mid-corner. Doing so properly is essential, as improperly dealing with understeer is the most dangerous thing you can do, and is responsible for most accidents at the track. “But I thought understeer was safe!?” Well, it’s not.

THE MOST COMMON, YET COMPLETELY UNKOWN MISTAKE WITH UNDERSTEER

Before we can talk about eliminating understeer mid-corner, we first need to understand the common mistake that most people make to get them in to really bad situations in the first place. This problem is turning the wheel MORE once the car has started to understeer.

When you think about it, it makes sense. If you want the car to turn more, you turn the wheel more, right? Wrong. What?! If you’ve asked your tires to turn a certain amount, and they can’t, how is asking them to turn even more going to help anything?

An example of this would be in a gym. A man is bench-pressing 200 pounds. He almost has the barbell all the way up, but he’s struggling. Then his friend comes over and adds another 20 pounds of weight to his barbell. In this situation, there is no way that the man will be able to lift the 220 pounds, instead, he’ll probably drop the weight on top of himself. This is no different with your car, all that will happen is it will understeer more and start to drive completely off the road.

GOT IT. SO NOW WHAT?

So, your car is starting to understeer in a corner. You catch yourself right before you instinctively add more steering. Now instead of having a serious understeer problem, you have options:

1) Reduce your steering input (turn less)
2) Reduce your throttle input (decelerate)

The first option is important to consider. Many times, maintaining your current speed with just a little less steering input is all that is needed to reduce your understeer. If doing so will still allow you to make the corner, you’re golden. If it’s clear that you’re going to drive off the road at your current radius, you move to option #2.

Option #2 has to be dealt with very carefully. As we know, decelerating will send load to the front, increasing front grip. This is a good thing, but too much, too quickly, will cause oversteer. For this reason, you need to be very gradual and sensitive. Lift slowly off the gas. With 10% less throttle will you make the corner? 20%? 30%? Are things really bad? Maybe you need to let off completely, or even brake. That’s OK, as long as you do it gradually and smoothly. If you simply lift off the gas and step on the brake you will cause oversteer that is so quick and so violent, you will spin, and exit the track sideways or backwards, guaranteed.

SO UNDERSTEER IS DANGEROUS, AND OVERSTEER ISN’T? THAT SEEMS PRETTY BACKWARDS

Oversteer can be dangerous, but unlike understeer, there are two major kinds of oversteer. There’s controllable oversteer, and uncontrollable oversteer. The oversteer you’ll experience from trail braking for example, is easily controllable because it’s gradual and you’re expecting it.

Another kind of equally controllable oversteer is power-on oversteer. This is possibly the easiest kind of oversteer to correct. You got on the gas too hard, too soon, and the rear tires are spinning? Let off. Your problem is gone. The only way to spin out or crash as the result of power-on oversteer is to try to be a drifting, power-sliding, hero that doesn’t want to lose a few tenths of a second letting off the gas and regaining traction. As soon as you feel that you’ve induced that kind of oversteer, lift your right foot and it goes away. That’s all there is to it.

SNAP-OVERSTEER

Now, uncontrollable oversteer almost always comes after bad understeer and is commonly referred to as snap-oversteer. This happens when you improperly deal with understeer, and this is usually what people think about when they hear the word “oversteer.” It’s scary, and it’s usually the only kind of oversteer that most drivers experience.

We’ll take a typical understeer example. You’ve failed to properly load your front suspension and/or you’re just entering a corner way too fast. The car begins to understeer. Because you haven’t read this post, you turn the wheel more to try to make the car turn more. Now you realize that the car is almost certainly going to go off the track and you’re running out of road. The outside of the corner is getting closer and closer. You panic and lift off the gas completely and suddenly, maybe even brake. In a split second you go from having excess steering input with no front grip, to excess steering input with an abundance of front grip. What happens? The car turns like you want it to, and then it keeps turning REALLY fast. You try to react by counter-steering, but by this point, it’s already too late. In fact, it was already too late when you lifted 2 seconds ago. You’re sideways, then you’re backwards, and now you’re spinning.

What should you do? Well, if you haven’t already, you should be hard on the brakes. In fact, as soon as you went more than about 45 degrees sideways you should have been hard on the brakes. But what do most people do? They don’t even get on the brakes until they’re going backwards, and even then, sometimes they still don’t brake. The net result is going off the track sideways or backwards, which can result in rolling the car or hitting a wall. All of which could have been avoided at that very moment you turned the steering wheel more.

That is truth about understeer.

———————————-

Here is some more good information coming from questions in later pages of this thread:

Quote:
Originally Posted by severe View Post
reading this i think i’m always way too jerky with the brakes

I wanted to make a slight clarification here as some people may misunderstand the “smooth” braking technique. When you get ON the brakes, it needs to be forceful, hard, and well, it can be down right jerky. Depending on your brake setup, suspension, aero, etc, the initial half second of braking is when most of the stopping is done. It’s extremely intense G’s and probably can’t be done properly without a good seat and harness. It’s also something that most people don’t do correctly, as it feels natural to progressively get on to the brakes (rather than basically slam them), but that actually increases your stopping distances, heats your brakes more, and reduces pad and rotor life.

To complicate things a little bit, there is the whole theory of “outrunning the load transfer.” This is rarely an issue in any track-worthy cars, but is more important in something like a dirt truck, where you have FEET of suspension travel, not inches, and it can actually take quite a bit of time (second+) for load to actually transfer to the front. In this case, slamming the brakes would instantly lock up the front tires since there is no load on them to do any braking. In an STI, it really shouldn’t be an issue, especially not with coilovers.

After this initial braking period, you’re easing off the brakes a bit (because at the slower speeds you’d lock up the brakes and/or trigger ABS), and doing your downshifting.

Once your downshifting and braking is done, you get in to the smoothness that is being discussed in my post, which is your brake release. Getting ON is rough, getting OFF is extremely smooth.

Quote:
Originally Posted by Chris05STi View Post
It was like your were in my head! Very good info, makes sense. We should have a Forza 3 meeting online for this!

Indeed. It’s actually fun to mess with in Forza. One of the biggest things you can improve in that game is not mashing the joystick all the way to one side. The same concept applies in that game, if you push the joystick all the way to one side (full steering lock) you’re asking your tires to turn more than they need to and causing understeer.

Quote:
Originally Posted by severe View Post
well yeah my initial braking is really hard, i found this to help my times sometimes i get a single chirp from the abs kickin in also. i havent been to the track yet but my seat time is mainly in autox and im pretty much learning.

 

i generally slam them hard right before the turn, but reading your post i realize what i never do is release them smoothly. i just drop the brake pedal and then get my foot on the gas. i dont slam the gas i have a pretty good feel for the throttle and how the car reacts to minute adjustments mid turn.

based on what you wrote though it seems like i should take a split second longer in my brake release. i dont know how practical it will be since our autox setups are generally really tight and technical but its worthwhile to try and see if it’ll help my times.

right now i can rotate the car a tiny bit with just throttle if i have the dif set to open, and it has some very slight understeer if i’m accelerating through the turn 1 notch up.

btw this has been on my mind, im generally screeching my tires around the entire course. i keep wondering if this is slowing me down or not. its right at the threshold usually i.e. if i remove a very small amount of steering input the screech goes away. i noticed most other guys aren’t so aggresive though (though most of them also have rwd)

Two things here. First, this obviously matters a lot more at the track than at an auto cross, but the concept can still be applied. No matter what corner you’re talking, a little trail braking will benefit your Subaru. It’s just going to be an even quicker brake release in auto x because you brake considerably less and you’re not going fast enough to be able to really get on the pedal hard without the ABS coming on.

As for tire screech, try not to rely on that. It’s more of a crutch than anything. Really good r-compounds and any slick are completely silent. You don’t hear any noise at all until you’re backwards. The same goes with lockup / ABS, they don’t chirp, you’re just see silent tire smoke in your rear view (or in front of you in an open wheel car ).

The key is to feel that understeer coming on BEFORE the tires have to tell you about it. First, because if you correct it really early or avoid it altogether, you’ll go much faster. The second reason is obviously as you get better tires you’ll stop getting that audible warning. Now, with street tires and street suspension, you still have plenty of time to correct if you wait too long because everything is somewhat in slow motion. If you go to a stiffer, lighter car with stickier tires, everything happens much faster.

Quote:
Originally Posted by santacruz02 View Post
Ben, I’d assume the size or width of the front tires makes a difference as well. Like possibly understeer was cause from not having enough tire to pavement?

This actually makes no difference, unless you’re suggesting running a DIFFERENT size tire in the front versus the rear. Whether you have 225’s on all four corners or 315’s you’re still going to have identical understeer characteristics basically. The only difference is you’ll get it at a slightly higher speed, but when the grip is still going to give up at the same point in the same fashion.

When you see cars with wider tires in the back than the front, they do this to artificially reduce front grip to compensate for oversteer problems. This is particularly noticeable in a Porsche.

You can actually mess with this in the opposite direction with a Subaru and it’s kind of fun. Like running 245’s in the front and 225’s in the back, assuming you can find a tire with the same overall diameter as to not slowly destroy your center diff. Another way to toy with this is to run new tires on the front and used tires on the rear. I used to do this quite a bit, but just know that if you trail brake now, you’ll DEFINITELY get oversteer.

Also, please keep in mind when I’m talking about new and used tires I’m talking about race tires, so the difference at most is 2/32’s tire depth. If you put new street tires and almost bald street tires you’d probably have a 5/32’s difference which isn’t so great for your center diff.

Last but not least, and the easiest thing to adjust, is your tire pressures. Running more pressure in the rear than the front will also help make the car more neutral, or more oversteer prone after aggressive trail braking.

Obviously you can adjust suspension settings, swaybar settings, etc, but I like to go to them last for the fine tuning. I’ll first start out with what makes the biggest difference (tires), then move on to aero (adjust rear downforce), and then move on to the suspension when the car is close to my liking.

A lot of people ask me why I run a considerably bigger front splitter than rear wing. Well, going back to our most basic load transfer example, the bigger splitter makes 400-500 pounds of downforce (front grip) versus the 300-350 that the rear wing makes (rear grip). The net result is more front grip than rear, which in a perfectly neutral car would cause oversteer, but in a Subaru just makes it more neutral.

Next time you see a Subaru at the track with a 10-foot wide wing raised to roof level and a little v-limited lip spoiler, you’ll probably laugh now that you understand what he’s actually done to his car.

Quote:
Originally Posted by thundercamel View Post
I wonder this also. I use the tire squeal to know to not push it any harder, and keep it squealing through the turn (on a track). I had just a little squeal the first time, but I’ve been pushing it louder the last 2 times.

The squeal is your car not wanting to turn, and you either giving it more gas or more steering input. Now, depending on the tires, this squeal could be AFTER it’s already understeering pretty badly, or when it’s just starting. This is why I tell people not to really use the noise as their indicator.

Now, assuming this noise is the start of understeer for you, hearing the noise isn’t terrible, but you could actually go faster if you got the car to rotate more initially before getting to power. The squeal would go away, you’d be on the gas sooner, and you’d have a higher exit speed. Depending on the corner, this may be almost impossible, especially in auto x since it’s all understeery, slow, tight corners. Still, brake a little later and get some good trail braking in and you may find that you can still rotate the car before the apex even in those little 40mph corners that seem impossible to get through without plowing.

Quote:
Originally Posted by GotSTI? View Post
I have had 8 hours of track time. 4 hours of class time. All of this was at Watkins Glen. Since I was new to it I was a novice. Still I was one of the fastest cars on the track rarely getting passed my first trip there and never getting passed my second trip there. Needless to say, I started getting Mario Andretti complex… thinking I was better than I was.

 

When I was at the track I heard people talking about late braking and I kept saying to myself I know these Brembos can handle me doing that. My first instructor had me do a lot of early braking whereas the second one did not. That’s where I started to get into some trouble. I saw a lot of the RWD cars braking realllly early. Which made me want to brake realllly late. Quite honestly, this practice had me focusing so hard on timing the braking I wasn’t thinking about my shifting and corner entry well. So, I hit the grass and got high up the curbing a couple times. This cost me a few extra track sessions before my instructor let me drive solo.

I learned to practice shifting smoothly on the straights so it would be better for the turns. It was too tempting to smash through gears on the straight away when you’d see a Z06 or something high powered in front of you. When in actuality being smooth and hitting the turn right made a bigger difference in catching those typ of cars.

Now I didn’t try trail breaking but found that I could turn in later then other cars. I found that tactic built a lot of confidence / straighter lines through the turns. A LOT less worry about going off track too! I came out most turns a lot faster with this tactic. It was my second instructors advice that seemed to make a huge difference with this. I wonder if you could write your thoughts about this?

Also, I am wondering what is the ideal RPM going into turns for our cars. I found that most of the time I was in 4th and 5th at Watkins Glen (4th for turns). The only time I hit third was with slower cars in front of me. However, that generated a ton of power… or was it that I was just able to get on it earlier into the turns? It was very apparent as I got the point by a lot when this happened.

Lastly, how does heel toe work into this? I’m sure that’s a whole other topic but I’d like your explanation on it as I can actually understand you!

Thanks Ben!

What you’re describing is late apexing. It’s always safer, and generally recommended when you’re learning a track. The worst that happens is you go a little slower overall through a corner if you apex way too late. Then when you consider the worst thing that happens when you early apex is you run straight off the track…late apexing is the way to go. Generally speaking, the true apex of a corner is not the same thing as the geometric apex. Most corners require a slightly later apex than the “middle” if that makes sense.

The concept is most often referred to as “slow in, fast out.” In other words, you brake a little bit more, you turn in a little bit later, but then you can get on the power really hard on the way out because you got most of your turning done in the first half of the corner. As you get more comfortable with trail braking, you can take that “slow in, fast out” concept and turn it in to “fast in, fast out” but it takes a lot of practice.

Most people, if not specifically told otherwise, will instinctively go “fast in, slow out” because they enter a corner too fast, understeer, scrub speed in the corner, and then get on the gas late at the exit. If you compare your “slow in, fast out” approach with their “fast in, slow out” you’ll always be faster, and that’s what you were seeing at the track.

Once you are 100% comfortable with the track (you know the line PERFECTLy) and you are 100% comfortable with your car and your driving, you can begin to try some trail braking. Essentially, this lets you carry more speed in to the corner while also reducing understeer. Yes, you can actually go faster and turn more. Thus the “fast in, fast out” principle.

On to RPM range for entering corners. I’d say 4000-5000 RPM. This gives you enough revs to let the gear wind out and not have to shift in a corner (bad!). On the flip side, I’d recommend shifting around 6500. There is no need to wind it all the way out to 7200 unless you’re on a track where the end of a straight is just perfectly at 7200 and it would be slower to upshift and immediately downshift. Otherwise, you’re being nicer to your motor and actually staying in a better power band (on most turbos). For example, on the engine I’m building I’ll be shifting around 7000-7500 even though it’s good for 8000-8500. There is just no reason to tempt fate or excessively stress components like that for little to no gain.

Finally, heal toe. Your heal-toe is done during phase 2 of braking. Phase 1 would be your primary stopping right at the beginning. Phase 2 is the rest of the stopping you need to do to make the corner, as well as your downshifting. Phase 3 is your brake release.

The reason for heal toe is that during phase 2 your right foot is on the brake, but you also need to hit the gas to blip the throttle when downshifting (for a rev-matched, smooth shift). There are two methods for heal toe, one is actual heal-toe (which I prefer, but most people don’t) where you rotate your foot in such a way that your toes are on the brake and your heal hits the gas pedal. The more common way is to toe-toe, where you roll your foot across the pedals so the left side of your foot and your big toe is on the brake, and the right side of your foot hits the gas. This is easier for people with big feet or when pedals are tightly spaced together. For whatever reason, even with my size 12 shoes and fairly narrow pedals, I still prefer to heal toe as I feel it gives me more control over my braking.

Quote:
Originally Posted by TorstenW View Post
Yeah, you’re buddy in the Exige that just outbraked you on the inside and is about to claim position, lol…….

 

ps; Very nice write-up, btw

.

That quote is how to get comfortable with trail braking. When you start applying it in a race setting, you’re braking later than that exige, entering the corner faster, and then getting on the power at almost the same time. The net result is usually a 5mph faster entry speed with a 10mph faster exit speed on say an 80mph corner.

That exige that late braked on the inside is off-line and is either going to have to forfeit his position, run in to me, or I’ll let him in and watch him overshoot the corner as I pass him again on the exit (most common).

Quote:
Originally Posted by subyalex View Post
AMAZING post, I can’t thank you enough or this insight Ben.

 

Now, if you could, maybe expand on how left foot braking may be able to assist with keeping the car neutral on long sweepers etc?

I learned alot fro this post, and made me realize how much I have to learn.

Some drivers left foot brake, most don’t. It’s more common in Rally, but you’d be surprised to find that most track drivers don’t bother.

When you think about it, what is left foot braking doing? Decelerating mid corner. What would lifting off the gas slightly (20%) in a high speed sweeper be doing? Decelerating mid corner. What’s the difference? If done properly, none, but you’re not using two feet, and you’re not heating up your brakes (not really a concern, but still a valid point).

Left foot braking is more of a “sounds cool” kind of thing to do, but in practice, the results just aren’t there (on the track). It’s not BAD, but it’s not better, and it’s generally harder to get comfortable with and is easier to screw up. Once you’ve gotten comfortable with being very sensitive with your gas pedal getting on the gas, it’s not hard to re-use that sensitivity getting off the gas.

I know a few professional drivers that like to do it, and I know about 5 times as many that don’t like to do it. It’s just personal preference. Personally, I’d recommend not. There are other things you could be learning and concentrating on that would make you go faster .

Quote:
Originally Posted by tyler_sti View Post
One thing I was going to add is that. If one were to left foot brake in lets say a nice long 90-100mph right sweeper like big willow. You’re entering the turn at either full or half throttle, at this point if you need to scrub off speed and release off the throttle you might initiate some over steer because the cars is already loaded on its left side at a high rate of speed. It dosen’t always happen especially if you have good suspension, but I’ve found letting off in mid turn can be very dangerous especially without enough down force on the rear. I like to left foot brake because no only does it keep me in boost for the exit, but the weight transfer isn’t as severe. IMO

First, even in a stock STI, turn 8 is a 120mph+ corner. If you’re lifting or left foot braking at 90-100mph…don’t. You should be flat through 8 if you’re comfortable doing it. Aim for the inside of 8 and keep the pedal flat, as you get to the end of 8 release your steering and let the car gently glide out to about 1 car width from the outside of the track, do your braking in a straight line for 9, and get back on the gas.

With coilovers and any sort of good tires and/or aero, turn 8 quickly becomes a turn that is more about balls than car capability.

But as for the left foot braking:

There is no difference in load and/or oversteer characteristics between left foot braking and gently reducing throttle. I’m not telling you to LIFT completely, simply if you’re at 100% throttle, back off to 90%. This is exactly the same thing as remaining at 100% throttle and applying 5-10% brakes, but it requires only one foot. If you’re getting oversteer lifting in sweepers, you’re lifting too much. You could lift less, go faster, and keep things neutral, if that makes sense.

If it’s easier for you to control the deceleration with left foot braking, go for it. It’s not a bad thing. In regards to the “staying in boost” part of it, you shouldn’t be lifting to the point that you fall out of boost anyway. Again, if your lift is that severe, that’s why you’re getting oversteer. 100% throttle -> 90% or 80% isn’t going to drop you out of boost, and you’re not going to be waiting for the turbo on the corner exit. The only way that would happen is if you lift completely.

Some of the terms you’re using are concerning though:

Quote:
Originally Posted by tyler_sti View Post
You’re entering the turn at either full or half throttle

That’s a HUGE difference. Which is it? If you’re thinking of the gas pedal in increments of “OFF, HALF, and FULL” you’ll benefit greatly by changing how you think about the gas pedal. There is a significant difference between even 90% and 100% throttle when you’re at the limit, backing off to 50% throttle is like braking in terms of load transfer.

Quote:
Originally Posted by tyler_sti View Post
I’ve found letting off in mid turn can be very dangerous

Again, letting off or lifting should mean 100% -> 90%, or 70% -> 50%. If you’re thinking of letting off as removing your foot from the gas pedal, yes, that is EXTREMELY dangerous.

The problem with Subarus is people can get away with that kind of stuff and develop extremely bad habits. People lift or even brake mid turn, and many times, nothing bad happens. They then start to think that it’s OK, and all this crap about driving smoothly and making subtle inputs doesn’t apply to them. Then they drive a car that isn’t nearly as forgiving (just about anything else besides an Evo or GTR) and have insane oversteer problems and go spinning off the track.

At the absolute LIMIT, a Subaru doesn’t behave much differently than those “other” cars that are considerably more sensitive to load transfer and throttle input. However, until you get within about 5% of that limit, it’s almost like the rules of driving don’t even apply to an STI (they just understeer). In a normal car, these rules start to apply when you get within about 40% of the limit.

Posted by: TJ | November 5, 2009

The First Racing Series

The Perfection Racing Team will be practicing/racing together on Sunday nights, starting around 5PM. The vehicle will be a stock Lotus Elise and the track will be Laguna Seca. Races/practice will be ten laps.

The race/practices will be held via private invite only. Since there is only room for eight drivers per race we may need to have an additional room administrated by a yet unselected volunteer. If you are interested in handling any overflow please let me know. My email is perfection.racing.fm3@gmail.com.

My gamer tag is Thomhend, friend me if you would like to play. I also suggest friending everyone else so you can race together in the off time as well.

We will only tolerate the pursuit of good racing. No intentional aggressive racing allowed. Drivers who continually crash into other drivers will be removed. If you wreck someone all you need to do is apologize and let them ahead of you on the track.

In the future I anticipate putting together a Class A Evora GT series. I suggest building and tuning the car in advance to the series starting.

Good luck!

The Perfection Racing Team is recruiting players to compete in team mode for C, B, and A classes with no assists. If you are interested in getting in on the ground floor of this racing team please send us an email at perfection.racing.fm3@gmail.com.

The car focus will be on the Lotus line of cars but I’m sure we will branch out to other cars.

You can also find me on life with gamertag Thomhend.

lotus_exige_gt3_concept_1

Posted by: TJ | October 20, 2009

New Game, New Leagues, New Opportunities

I haven’t finished playing FM2 completely, dispite several hundred hours of play time, so I wasn’t planning on buy FM3 right off the bat. Then I played the Forza 3 Demo…. And then I prompty went out and preordered the game.

I am just getting into tournaments in Forza 2 and would like to have a dedicated team and tournament league in Forza 3.

If you are interested in joining this new team, appropriately dubbed Perfection Racing, shoot me an email at tjkastning@gmail.com.

Later I’ll be writing reviews on tracks and just where the fastest line is.

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