[FIDDYgg]

A last minute track event came up and I've been really wanting to see what the 340i can do in a controlled setting, first time tracking the 340i, basically stock. The car drives really great in stock form honestly and the Bridgestone Potenza S001 run flats were actually surprisingly decent but they really didn't stand a chance with no negative camber. I've been looking for an excuse to get on some Michelin's anyway

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No incidents, just some destroyed rubber shoulders.

[drdino]

Stock pressures?

[340iGUY]

Since this happened after one event, I say you were too aggressive on the corners.

[FIDDYgg]

Originally Posted by drdino

Stock pressures?

I did a little research for starting cold pressures 30F/36R and made adjustments each session but it was to no avail... I'm very familiar with this track as I've raced superbike there for years, so I was hustling at a pretty good clip. I think without negative camber or just driving slower (boring?) it's probably unavoidable.

Originally Posted by 340iGUY

Since this happened after one event, I say you were too aggressive on the corners.

Too aggressive? What's the point, if not going all out?

This is a very tight technical track, with very abrasive track surface (loads of grip), so again without optimized alignment for track use I think it's inevitable when the pace is up there.

[jsouth]

I had a similar experience with track days in a Datsun 510 several years ago. My pressures were too low, AND I was drifting too much. Fun as could be, but I got some lessons and changed the amount of rubber loss in corners while going faster. I have no idea if that was an issue for you - with bike experience on that track probably not.

But I sure miss track days!

[jmg]

Originally Posted by 340iGUY

Since this happened after one event, I say you were too aggressive on the corners.

Too aggressive for the setup. With proper camber he can be this aggressive or more.

[RMachuca3d]

More air pressure, tire rolling over on sidewall is a clear sign that its too low. Camber will help, but the clear issue here is the lack of air.

[FIDDYgg]

Originally Posted by RMachuca3d

More air pressure, tire rolling over on sidewall is a clear sign that its too low. Camber will help, but the clear issue here is the lack of air.

I had the same thought, I added about 8 psi after I noticed the sidewall rolling over and was coming off the track hot around 46psi, it was a cold day as well.

All of my tire pressure experience has been with motorcycle slicks running 25-36lbs hot so I was a bit lost on pressures for the F30.

What are you guys running for cold pressures? Target hot pressure?

[RMachuca3d]

Originally Posted by FIDDYgg

I had the same thought, I added about 8 psi after I noticed the sidewall rolling over and was coming off the track hot around 46psi, it was a cold day as well.

All of my tire pressure experience has been with motorcycle slicks running 25-36lbs hot so I was a bit lost on pressures for the F30.

What are you guys running for cold pressures? Target hot pressure?

I ran mine (throw away cheap track tires to beat on, achiles ATR sport 2's) typically around 40psi hot, so in the ballpark, BUT different tires with different sidewall strengths can differ in what an optimal pressure would be, plus the grip the tires offer can also affect how much sidewall rolling there may be, as grippier tires have higher peak lateral grip which will increase sidewall deflection under load.

[drdino]

Originally Posted by RMachuca3d

More air pressure, tire rolling over on sidewall is a clear sign that its too low. Camber will help, but the clear issue here is the lack of air.

This, hence my question about pressures. Had the same issue the first time I tracked one of my previous cars (loads of shoulder/profile wear) which was fixed by using higher pressures. Just look at how much of the sidewall writing has been lost, camber will help a bit but it can't do miracles...

[MacklinUSOB]

This wear is exactly what you should expect pushing harder than the street tires and camber can keep up with. Running higher pressures is a huge trade off as just 1 or 2 psi can really shift the handling balance as the tires warm.

Camber on these cars DOES do miracles.

[nickf30]

Your tire is clearly rolled over:

1) Keep PSI high until it is up to temperature. Coded the tire temp/psi display and watch that closely.

2) Our car is heavy for its tires especially the front tires. Drive as smooth as possible and try to shift weight to the rear of the car.

3) Get more seat time: more track days / autocross / karting. In my personal 0.02, track is not the safest place to test the limit at the beginning. Spend some time in autocross helps a lot in understanding the limit of the car and how to process the feedback. It is much safer to push the limit in autocross environment when you spin at 40-50 mph instead of 120 mph.

4) Get extreme summer tire 200tw: these tires have much higher heat tolerance (wider operating window) will allow you to push the car longer / more consistently.

[zinner]

I run about 36 PSI hot on RE-71R. Depending on the day I shoot for 28-30 psi cold.

[AmuroRay]

I did a track day on my DSW 06's and they held up ok - Trash at anything resembling grip though.

[Polo08816]

Originally Posted by jmg

Too aggressive for the setup. With proper camber he can be this aggressive or more.

I'm at -2.25 degrees on the front with:

- M Performance Suspension Kit
- OEM Wheel hubs with an additional -.50 of camber
- M3 LCA and TS

Even that is not enough negative camber for heavy track use, it's more than sufficient for street use.

I think for tight tracks you may want to be in the neighborhood of -2.50 to -3.25 degrees of camber.

[brigade24]

so many factors...someone mentioned that these cars come with too little tire. I 100% agree. I ran 265 wide all round with -2.9 degrees of camber and at the limit would still notice the outside half of the tires wear out more quickly than the inside half...i usually run about 34psi hot on my re71r.

camber plates and bushings are the two things i have done that have had the most significant impact on tire preservation. the bridgestones you were using are decent tires, they just a bit narrow for the load under transfer.