What pressures do you run on what aftermarket tires ?
- Thread starter cosh68
- Start date
This is one of the most confusing areas of autocross for me, every single FWD driver I've talked to does it differently and has different justification for what they do.
On my 205/50 Rivals, anything under 40Psi upfront rolls over the triangles on the sidewall, I'm not sure if that's okay, but in my head the triangle seems like its pointing at where the sidewall starts. I have also run into some drivers like you that run much lower pressures up front, as low as 28, so I'm not really too sure how i should go about this.
For the rears I've tried anything from 30-40, and most drivers I've talked to are either running ~33 because its "predictable", or they are running 38-40 for more rotation. I've been running 35 just to stay in the middle, but the patch is definitely somewhat small, i may try lower.
On my 205/50 Rivals, anything under 40Psi upfront rolls over the triangles on the sidewall, I'm not sure if that's okay, but in my head the triangle seems like its pointing at where the sidewall starts. I have also run into some drivers like you that run much lower pressures up front, as low as 28, so I'm not really too sure how i should go about this.
For the rears I've tried anything from 30-40, and most drivers I've talked to are either running ~33 because its "predictable", or they are running 38-40 for more rotation. I've been running 35 just to stay in the middle, but the patch is definitely somewhat small, i may try lower.
depends really on the overall setup. With 17's you shouldn't need to run as much pressure as you would with 15s.
For me I run 40 in all 4 for driving on the street. For autocrossing I run 36-37 in the front and 45ish in the rear. That is with 195/50/15 star specs, bilstein coilovers and -2.5 degrees of camber in the front. I have never checked the temps on them yet though.
For me I run 40 in all 4 for driving on the street. For autocrossing I run 36-37 in the front and 45ish in the rear. That is with 195/50/15 star specs, bilstein coilovers and -2.5 degrees of camber in the front. I have never checked the temps on them yet though.
CRG Racer24
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- '11 Mazda2 GX-Convenience Pkg.. Warranty Voiding Mods
I too run 40, or just a hair above on the street.
Same here
racercentral
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- Mazda2 Sport
Using Direzza IIs, 205x50x15. For street use, 34lbs on all four;
Haven't autoxed with these tires, will use 36 front, 40 rear.
On track days, have been starting with 35 front, 32 rear. Check pressures before and after each session. At Buttonwillow & at Thunderhill this year found the after session pressures were usually 43-44 front & 37-39 rear. Pressure dropped a bit between sessions, depending on how cold & the time of day & (yes) which side of the car faced the sun. The grip seemed to be there, rollover looked ok. Tried temps last year, (Star Specs) but tires cool off too much on the cool-off lap to be accurate, but outside & middle about same, inside slightly less, but figure that's because car is stock & no negative camber.
Haven't autoxed with these tires, will use 36 front, 40 rear.
On track days, have been starting with 35 front, 32 rear. Check pressures before and after each session. At Buttonwillow & at Thunderhill this year found the after session pressures were usually 43-44 front & 37-39 rear. Pressure dropped a bit between sessions, depending on how cold & the time of day & (yes) which side of the car faced the sun. The grip seemed to be there, rollover looked ok. Tried temps last year, (Star Specs) but tires cool off too much on the cool-off lap to be accurate, but outside & middle about same, inside slightly less, but figure that's because car is stock & no negative camber.
