traction roll question

[loopy]

Anyone has a cure for 911 GT3 traction rolling when racing on RCP track - smooth surface side?

I've changed the tires from F/20 R/10 back to stock and it seem to help a bit. The car rolls under hard braking and cornering.

The car is fully optioned with x-speed motor, ball diff, gyro etc

[MrNanoTrax]

very common occurence with the 911... you need PN Racing 45 degree tires (Kyosho 40 gives u too much grip while 50 is too hard for RCP/Rubber; stock is F/20, R/10 btw). you can make steering angle and servo reaction adjustments to counter-act this as well. if you know what you're doing, the 40s will fine. my setup is F45/R15 and its tough to beat the times it registers. i've even done well with the Atomic 35's but u will need to have patience and pretty good with throttle control to keep it on all fours.

u should run a 2-plate setup in your ball diff (with or without the containing spacer is up to you, i go without). if you're using the Perfex KT-18 Transmitter, back down your braking to a minimum so you don't lock up and cause the roll. those tips should get ya where you want to be but due to the fact the 911 GT3 is most narrow track width, its automatically prone to this problem.

good car choice though

[Jellis]

what is a 2 plate set up???

[MrNanoTrax]

the ball diff incorporates spacer plates allowing you to adjust the spring tension which of courts affects the amount of action in the diff. review the ball diff set support doc which has diagrams of this explaining the effect of each tension setting.

also, i forgot to mention that you should probably reduce your steering angle to reduce roll, the softer the compound, the greater the reduction. you won't get a very tight radius with a reduced steering angle but at speed, the car will turn on a dime.

[loopy]

thanks for the tip. Its not my car but friend's, though after driving it I'm considering it as my next purchase.

I have now rebuilt the diff and put on the stock fronts for him. The car now understeers but traction roll is gone and so is the sharp turn in. I think I still prefer driving my lambo.

[fraz]

Originally Posted by loopy

thanks for the tip. Its not my car but friend's, though after driving it I'm considering it as my next purchase.

I have now rebuilt the diff and put on the stock fronts for him. The car now understeers but traction roll is gone and so is the sharp turn in. I think I still prefer driving my lambo.

Absolutely glue front tires and do it carefully as to not get glue on sidewalls. gluing sidewalls is yet another more extreme traction roll cure but you should creep up on this solution. The edges of the tires lift/peel under load with the high grip so gluing helped a ton.

Nano, I kind of agree with the 50 vs. 40 assessment but I'll tell ya from testing it is kind of chassis/diff based. My ball diff Porsche 962c I run 40/10 and I have to dial down dual rate a good chunk. On my Lambo with gear diff I run stock 50/10 and it is dialed and I even had to take a little dual rate out on that. Sounds like those narrower chassis seem to be prone to traction rolling so I will be testing some narrow chassis combos next.