Lower is generally better low pressure increases the contact patch with the road and reduces vibration and shock through tyre when launching.Ben
For street tyres - 18-22psi is normal ...it gives the tyre more bite and more flex which is needed.I left mine at 40psi just to see what I could do in true street trim. I wasn't getting much wheelspin (thanks to a dying clutch which was doing the slipping instead) so I left the tyres as is.Previous meets I've gone to have been done with pressues in the very low 20's.
Speaking of which... ...when are you heading down Nathan?There aren't too many more Wed night meets this season!
40 for track? I use 32psi when using street rubber, and 28 with R compound rubber. THis gives a semi firm ride with a bit of give in the tyres (ie so its not sliding at the slightest bump on the road or because of weight transition).Only time I put pressures up at the track is normally in the rears when I want to have a bit of fun! Drag racing always use lower pressures so the tyre walls have more give when given sudden power (ie acceleration from a standing start). You don't need tirewall stiffness in drag racing as there are no corners that stiff sidewalls are needed for.
Ummm..... wow Those are some low pressures Franz. Maybe VIC tracks are a little smoother (I doubt it), but I felt siginificant improvement when running tyre pressures much higher than that on the track (this is with 17's).Ben
So, Franz, you beat your previous PB by loading up your car and leaving the tyre at 40psi? how does that make sense? some other mods since last outing?
it came down to an awsome launch his 60' time was 1.8, that's pretty damn good time. best i've done was around the 2.2 mark and i ran a 13.6. but u have to remember he'll then be carrying more speed throughout the track than say what i would be which gives him such a good time. + its typical of franz to pull off somthing like this, you only have to watch the video of him powersliding his zed around mc motorsport, clipping a cone and the damn thing still remains standing! 8-} Cheers,Red Z.
I'm talking cold or at best luke warm R Comps would be different, a proper track tyre will have a nice thick tyre wall, which is exactly why you add a lot of pressure to street tyres to try and counter their weak side walls.Have a fiddle with pressures at the next track day, no one said I was right in my experiences Ben
First wednesday I actually have my car... and dont have to work Im down there guaranteed. I cant see my car being back from the painters by tomorrow, and next wednesday is my birthday so Im heading down to collie for the night to spend it with my folks. The following wednesday I have off so that will be the night Im thinking. All I need is a helmet right?
I am talking cold press at 40psi It so you dont roll the tyre off the rim when you hit hard into a corner and secondly you would tend to slip moreso than flip which is inclined to be a little less expensive!!Luig
40psi is correct for street tires at the track. If they are around the 28psi mark, they will go much higher when hot as the sidewall flex's more which heats the tire up. Semi - slicks are different though and usually set to around 28psi.
Helmet, long sleeve pants, shirt and shoes Let me know if you go down; I would like to go and spectate
Yep - it doesn't make sense I was talking to Risk last night about this; it doesn't make sense.The only difference done to the car between my 13.2 run and the 12.7 run was 0.2bar more boost and a cleaned up fuel map.I think the combination between a sticky track and a slightly slipping clutch it created the perfect combination. I can't think of any other reason - nothing else makes sense!
I'l try and keep wednesday after next free.. and plan on then. Will have to get a helmet sorted and maybe try and find some slicks. Come with a helmet Franz and maybe you can try a 1/4 in my car.
