Tire pressure on a promod

Is there any where a guy can get some guidelines on what pressure to run and how it affects the launch with different pressures ?

 

The more psi. you run in the tire the more traction you'll have, the less psi the easier it is for the tire to spin ='ing less traction. Those are very basic statements but they don't need to be overly complex. In theory you could say (I suppose) that the less psi. you run the easier it is for the tire to rotate on the top end...thus making the car think it has a different gear....but that's getting into some bro-science. Which tire (size and compound) are you running? Are you using liners, tubeless liners, or beadlocks?

Brandon Booher
NHRA TAD #34

 

Bingo. There will be a certain pressure that generates maximum thrust, up or down are both less, and there ain't no such thing as too much traction in a P/M.

 

any idea where the over inflation starts to decrease traction on the 2055 hoosier34.5 hoosier Mike?

we use a higher tire presure than most here seem to use @6.5 to 6.75 psi as we have found we can use a 2.04 low without pulling timing and get consistant sub 1 sec @60 and close to 3000 rpm at .5 which the car seems to handle, i wonder how far we can push it presure wise 2700lb legal 1/4 mile car for anyone else with any ideas

 

pressure

If you search just a few years ago people were running a lot more air in the Hoosiers trying to control shake. I've heard of one promod tuner that likes close to 7 psi. Most like 6.0 to 6.5.

I swear i've seen wheelspeed changes moving the pressure around 6.1 to 6.5. It picked up speed with lower pressure as stated above.

We've been running on a track with a decent start and then junk about 2.0 seconds out. I was advised to run lower pressure to help hook downtrack...not sure of the logic on that one but it seems to work ok.

 

Do you happen to remember at what pressure the largest contact patch was? How low can you go on tire pressure? I have heard some people mention it gets a little hairy on the top end with less then 5.5.

 

The other thing over inflation does is strengthen the sidewall. The sidewall squat effects the weight transfer as well as how much you can stretch the sidewall while trying to spin. I honestly think the sidewall strength is what makes the difference at higher PSI. At lower PSI you notice the ripples on the outside tire print as it leaves..That's actually the sidewall stretching and changing the shape of the tire. Higher PSI looks much smoother assuming you can achieve the wheelspeed and traction you're looking for. That being said, one could conclude the weaker the sidewall, the easier it would be to square the tire and shake.