[Baker]

I’ve been autocrossing my car here and there for the past 4 years. This is my first exposure to autocross in any car. I have had the car full bolt on and tuned for the entirety of this. The car has always been extremely tail happy and I have just chalked it up to being a RWD car on the stock supercar 3’s which take time to get heat in them. Yesterday I attended an autox school where I was able to get about 10 runs in the morning and 10 in the afternoon which got the tires sticky. An instructor rode with me who is use to running RWD V8 cars, his advice to me was that my throttle inputs were way to aggressive. He asked to drive to show me how it should be I agreed. It only took the first turn for him to ask what the hell kind of throttle mapping I had because the tiniest input upset the car. There isn’t any kind of progressive power when applying throttle. Hearing this made sense I’ve learned to drive the car but always fighting the car. He explained a lot of tuners tune for drag racing and the throttle tip in is overdone. Does anyone have any advice on a tuner that would be able to tune this correctly. Or should I try to get a tire setup that can handle the aggressive throttle.

[DaveC113]

It'll make a big difference to use Track mode and within track, enable the PTM (Performance Traction Management) modes, or hold the traction off button for 8+ seconds to disable both traction and stability control. This will also change the behavior of the rear diff, as well as linear throttle mapping.

You can also independently choose what steering weighting you want, track is a bit heavy imo... I also keep the exhaust in track mode all the time. You can't change throttle mapping independently of mode though.

If you're going to autox I'd get dedicated wheels/tires. 18x12 square is possible, but if you want to stick to street class, go oem 1LE sizes but in 19" diameter. Bridgestone RE71RS tires, 295/35/18 or 305/30/19 (all 4).

Also get an alignment with max camber and zero toe front, 1/16-1/8 toe-in rear.

Good Luck!

[JamesNoBrakes]

Track mode track mode track mode, for the throttle.

I also like the heavier steering in track mode, that helps to minimize you getting the steering angle too far, which will send you spinning, but the throttle is a much bigger part of it.

Sport mode is pretty horrible for track stuff. It's great for getting into 4th from 1st, but otherwise, it is significantly regressive. If if the pedal goes 3", it gives you more than half the available throttle in the first 1". It also means when you are at 4500rpm and you "punch it" from there...you don't really go, that part takes fun out of higher RPM driving IMO. At higher RPMs you have a lot less throttle response in sport mode.

I will often do the first lap or maybe two in PTM Race, and then after that it's everything off. Even PTM Race robs significant time/power.

[eimarshall]

With regards to the throttle mapping, I think Randy Pobst commented that he used a pedal commander or something to make the throttle response curve more linear. A lot of the throttle response "solutions" simply hasten the opening of the throttle to make the car feel more powerful, when in actuality they are making it less modulatable/controllable. I'd talk to your tuner.

Also, PTM, as above.

[Baker]

I have used probably every PTM with the exception of track mode and holding the button to turn everything off. We actually found that sport mode and competitive mode was the least violent but still small inputs upset the car. I do have the GM track alignment. I will most likely go with 18 x 12 as I am already in CAM due to the other mods. I have no issues with my tuner however he is use to drag racing. Was looking for a a tuner that had experience with track / autox cars.

[DaveC113]

Originally Posted by Baker

I have used probably every PTM with the exception of track mode and holding the button to turn everything off. We actually found that sport mode and competitive mode was the least violent but still small inputs upset the car. I do have the GM track alignment. I will most likely go with 18 x 12 as I am already in CAM due to the other mods. I have no issues with my tuner however he is use to drag racing. Was looking for a a tuner that had experience with track / autox cars.

I wrote a post on the 18x12 square setup using Apex 18x12 et 41 wheels. It's doable with magride but a pretty tight fit!

[VR Baron]

Originally Posted by Baker

I have used probably every PTM with the exception of track mode and holding the button to turn everything off. We actually found that sport mode and competitive mode was the least violent but still small inputs upset the car. I do have the GM track alignment. I will most likely go with 18 x 12 as I am already in CAM due to the other mods. I have no issues with my tuner however he is use to drag racing. Was looking for a a tuner that had experience with track / autox cars.

I haven’t seen people post up of really having the car tuned for autocross. Most use a DSC controller specifically for tuning the mag ride or getting the GM autocross tune. Though from what DaveC113 said on other posts it’s a bit much for stock suspension and tires as it helps the EDiff to help the car turn in faster and the rear rotate faster.

[JamesNoBrakes]

Originally Posted by Baker

I have used probably every PTM with the exception of track mode and holding the button to turn everything off. We actually found that sport mode and competitive mode was the least violent but still small inputs upset the car. I do have the GM track alignment. I will most likely go with 18 x 12 as I am already in CAM due to the other mods. I have no issues with my tuner however he is use to drag racing. Was looking for a a tuner that had experience with track / autox cars.

Honestly, I would invest more in learning how to drive it at AutoX. That means time, playing with the settings, tire pressure, so on. You might hose a few events, but you should record your findings and see what you can do to improve your confidence and times. What you are reporting does not sound right, racing against cars like cayman, miata, vettes, fiesta ST and way too many others to list. Basically, a mix of FWD, RWD, front mid and rear engine layouts. Occasionally a car spins out, but not very often and there's nothing special about the camaro that would make it spin out more than the vast majority of these. Steering angle and power application has to be an important consideration. You can't just keep whipping the car harder and harder as you go faster, sometimes that's the thing you want to do, but you have to realize every action has a consequence. The faster you go in a section, the earlier you need to now brake for the next. Going "faster" doesn't often feel like it, it's only the numbers that really show it.

[joelster]

Could be that your rear toe adjustment is out of whack. My cars makes 588rwhp, and it tracks really good out of corners. Obviously I can blow the tires off at will if I mash the gas, but it will handle aggressive inputs on most turns. I'm running -1.5 degrees of camber, and they are toed in -.125 as well.

Also, what tires are you running?

[Christian1LE]

Originally Posted by joelster

Could be that your rear toe adjustment is out of whack. My cars makes 588rwhp, and it tracks really good out of corners. Obviously I can blow the tires off at will if I mash the gas, but it will handle aggressive inputs on most turns. I'm running -1.5 degrees of camber, and they are toed in -.125 as well.

Also, what tires are you running?

Not sure if that was a typo but if you're running -.125 you are toed out, not in.

[MatthewAMEL]

Originally Posted by eimarshall

With regards to the throttle mapping, I think Randy Pobst commented that he used a pedal commander or something to make the throttle response curve more linear. A lot of the throttle response "solutions" simply hasten the opening of the throttle to make the car feel more powerful, when in actuality they are making it less modulatable/controllable. I'd talk to your tuner.

Also, PTM, as above.

No, Randy did not use a add-on. He commented he would like to see a more linear throttle while on track. GM changed the Track mode to give just that.


Pedal commanders with this car are the fastest way to a check engine light and limp mode on a track day.

[DaveC113]

Originally Posted by VR Baron

I haven’t seen people post up of really having the car tuned for autocross. Most use a DSC controller specifically for tuning the mag ride or getting the GM autocross tune. Though from what DaveC113 said on other posts it’s a bit much for stock suspension and tires as it helps the EDiff to help the car turn in faster and the rear rotate faster.

My DSC magride controller is for sale... If anyone's interested PM me, it's the most recent model with current DSC programming. I think I have a program for VIR on my laptop too...

DSC is great for those who find the concept appealing, you can have shocks that react to what the car is doing preemptively based on brake and steering inputs, and more. As an engineer I can get carried away with this sort of stuff, and I don't have the time to spend on dialing it in. It requires some time and effort to test n tune the DSC along with a nuanced understanding of suspension to get the most out of it. DSC also offers active coilovers that work with the controller. OTOH, it's not like GM is incompetent at programming their own magride shocks, oem is good but the main difference is DSC uses more info than OEM to decide on shock behavior.

If you get the ediff tune on stock tires and sus setup it's still better and more fun to drive, but you can literally feel the rear end locking and unlocking, there's a bit too much exit oversteer and if you're not smooth the rear diff will actually unsettle the car. With 200tw tires and a stiffer front roll bar you're good to go though, rear diff feels totally normal except it puts power down better on exit and is more predictable. It may also unlock on corner entry faster, but there's some debate on that, feels like it does to me. Diff tune is FS-legal now too.

[Msquared]

I think we need to go back to basics here with the OP. Baker, what mods have you done to the suspension of the car? Stock SS 1LEs are not "extremely tail happy." They have a proclivity to kick the tail a bit on throttle when exiting a corner due to the stock eLSD tuning. The GM autocross eLSD calibration solves that, but even without it these cars are highly competitive in Street (stock, essentially) class. The kinds of things that upset the forward-traction balance are aftermarket rear suspension links with poly bushings, cars that are lowered such that the outside rear suspension hits the bump stops while cornering, rear toe out, or a way-too-stiff rear swaybar.

If your car literally has an out-of-kilter throttle response (compared to a stock LT1 Camaro), then you need to look at your bolt-ons and/or tune. For instance, an aftermarket throttle body could cause this, especially if there's some kind of "hole" in the A:F curve coming off throttle. If tuning software (e.g. HP Tuners) allows the throttle map to be changed (it probably does) and you've had someone tune the car, then all bets are off. You need to compare your mapping to a stock throttle map to see how it's different: most tuner's idea of improved mapping is probably to give most of the throttle in the first 1/4 of pedal movement (as others have alluded). That's stupid. The stock mapping in Track mode is fairly linear, and in fact I wish we could use that mapping in Touring mode.

My suggestion is to find someone who is a good autocross driver in a stock 1LE and ask them to drive the car and give you their impressions, and also to figure out how your current throttle mapping compares to stock in Track mode.