Correct Understeer by Tire Pressure
#1
Melting Slicks
Thread Starter
Correct Understeer by Tire Pressure
I have always been advised that to correct/address understeer,
we should increase front tire pressure, and decrease rear tire pressure.
For Example, running Toyo R888, I use 35 front, 31 rear.
But yesterday, I was told to do EXACTLY the opposite.
Truthfully, I did the opposite (31 front, 35 rear), and could not really tell any difference.
So last night I researched (Google)... holy crap, what a lot of "hits".
And they all are in conflict with one another.
Increase:
http://www.tirerack.com/tires/tirete....jsp?techid=58
http://www.thesmokingtire.com/2012/m...teeroversteer/
http://rennlist.com/forums/racing-an...ndersteer.html
Decrease:
http://www.execstudio.com/tech_suspe...understeer.htm
http://www.drivingfast.net/car-control/understeer.htm
So....... experts ?????
.... what are we supposed to do ??????????
we should increase front tire pressure, and decrease rear tire pressure.
For Example, running Toyo R888, I use 35 front, 31 rear.
But yesterday, I was told to do EXACTLY the opposite.
Truthfully, I did the opposite (31 front, 35 rear), and could not really tell any difference.
So last night I researched (Google)... holy crap, what a lot of "hits".
And they all are in conflict with one another.
Increase:
http://www.tirerack.com/tires/tirete....jsp?techid=58
http://www.thesmokingtire.com/2012/m...teeroversteer/
http://rennlist.com/forums/racing-an...ndersteer.html
Decrease:
http://www.execstudio.com/tech_suspe...understeer.htm
http://www.drivingfast.net/car-control/understeer.htm
So....... experts ?????
.... what are we supposed to do ??????????
#4
Melting Slicks
I'll add some more. You can have to much or to little air pressure that will cause understeer. Some where depending on the tire, driving style, and car setup, you have a sweet spot for air pressure for maximum grip. You might still have understeer though. If so, then I would look at the rear. I personally would add lots of air in the back, until I got the desire results. When I get home, I would make a sway bar change etc.
Steve
Steve
#5
Melting Slicks
I know I can reduce oversteer by reducing rear tire pressure only on my Z28, done it many many times.
Seems to reduce understeer the same would apply in the front.
Reduce front, add to rear for understeer.
Understeer is less front grip than the rear, take away rear grip(more air) add front grip(less air).
Seems to reduce understeer the same would apply in the front.
Reduce front, add to rear for understeer.
Understeer is less front grip than the rear, take away rear grip(more air) add front grip(less air).
Last edited by FASTFATBOY; 05-11-2015 at 10:15 PM.
#6
Here's a link to the Goodrich g-force tire manual:
http://www.bfgoodrichtires.com/asset..._NEW_FINAL.pdf
.
http://www.bfgoodrichtires.com/asset..._NEW_FINAL.pdf
.
Last edited by B Stead; 05-11-2015 at 11:38 PM.
#9
Tech Contributor
Tire pressure changes are more about fine tuning. If you have significant understeer, you need to address it via the alignment.
Of course it really starts to get complex when you add sway bars and spring rates into the conversation!
Of course it really starts to get complex when you add sway bars and spring rates into the conversation!