Drag Radial, tire pressure

[xtweakerx]

Where are a lot of you guys running you're tire pressure for your drag radial?

I'm using M&H Drag Radial : 275/50R17

 

[psfracer]

I run M&H 325's and I use 17psi.

 

[2oo5GT]

Just got to test them out. I would start with 19 and work down to maybe 16. Will you drive them to the track or swap them out at the track? I drive mine to the track then lower the pressure but remember to bring a mini air pump, i got one from Wal mart for a few bucks and it plugs into the cig

 

[fin1]

M/T ET Street Radial @ 12psi

 

[xtweakerx]

wow 12 psi is low for a radial i would think, nice.

I ride mine to the track, I've used them before already. Their is a air pump at the track.

I was going to start off @ 17psi.

So far the best I've done was @ 15psi but it only managed a 2.0 60 foot, i need to work on my launch and this time around I'll have a tune & intake so I won't be bone stock.

 

[xtweakerx]

How are u guys launching w/ the stock suspension and radials?

4,000 rpm and dump clutch? Side stepping clutch?

 

[2oo5GT]

I launch at 3000rpms, easing out the clutch till i feel it grip and floor it. But my Nitto's are crap last week at the track, I had to play with it out of the hole. If i still had the MT's i would probably launch at 4K.

12psi, does your rim spin in the radial?

 

[xtweakerx]

what psi do u rock out 2005GT?

 

[xtweakerx]

What do you guys torque you're radials down to when u put them on your car?

 

[stkjock]

m y best run on my BFG DRs I had the pressure down to 14 pulled a 1.79 60ft leaving around 4000 and slipping it out... I'm still learning to launch it as well. The torque spec on our cars I believe is 100ftlbs

 

[xtweakerx]

thx, going to the track on wednesday first time w/ tune and intake.

 

[ArtQ]

I launch at 6000 RPM slipping it out. M&H 275/50/17 between 23 and 25 psi depending on track, consistant 1.68 60"s

 

[xtweakerx]

wow that seems like a lot of air pressure compared to everyone i talk too.

Have you tried w/ lower PSI ? what happens?

I've been told slipping the clutch really damages parts but those are impressive 60 foots.

 

[stkjock]

the only damage slipping does is wearing the clutch...

dropping or dumping shocks the drive like much more and could break stuff

 

[ArtQ]

wow that seems like a lot of air pressure compared to everyone i talk too.

Have you tried w/ lower PSI ? what happens?

I've been told slipping the clutch really damages parts but those are impressive 60 foots.

With my set up I found that lower pressures allows the tires to cup and you get less contactpatch.

 

[ArtQ]

Tire picture shows good sidewall flex and contact patch at 24 psi. This a 1.68 60'.
Full car picture shows very little squat and the front end is high enough to transfer the weight to the rear without wasting a ton of suspension travel before car moves forward.

 

[xtweakerx]

what do u guys recommend for me to do w/ my setup for psi and launch?

stock suspension, axle-back,intake,tune,drag radial.

 

[ArtQ]

Practice your clutch release with the car off. Let the clutch out to the point were you feel it go overcenter. Fully engaged but dont take your foot off. Get a feel for this point. Move the pedal down a little from fully engaged. Memorize this position. The point where it's just prior to fully engaged. Now push the clutch down and hold it just off the floor. Bring it up slowly till you get to that just prior fully engaged point. Push it back down to just off the floor. Now practice releasing the cluthc quickly to that just prior point. Do this till you automatically stop just prior.
Now when you stage, after lighting the second light bring your rpm up to about 5000. Don't worry about reaction times yet. Bring the clutch pedal just off the floor and hold it after lighting the second light. At the third light quickly, like you practiced, release the clutch to just prior to fully engaged. The car will lauch, hold that clutch position til you feel like the tires are biting, stomp the gas and let the clutch out the rest of the way at the same time. When you hit 6200 rpm, while holding the gas to the floor, punch the clutch pedal and at the same time pull it in to second at the same exact time, same with third. You will most likely not need fourth with your gears. Most tunes rev limit is set at 6800 so you should be good shifting at 6200.
Start your pressures at 28 psi. With stock suspension I expect you will have a wheel hop problem. See how that goes. LCA's and UCA should be your next purchase.

 

[xtweakerx]

thanks