Well, this weekend will be the first time taking my fully built turboed em1 to the track. I am making 430whp and am running 225/50/15 mickey Thompson Et Street R's. What should I put the tire pressure to? Also, I have launch control and right now I have it set too 6k rpms building 10lbs of boost off the line. Is that too high?

 

Id say you will find a happy point with the tire pressure somewhere around 10 psi cold. A good burnout will get them ready to go. dont forget to preload. after you light the first staging light, with the ebrake on kinda drag yourself up by working the catch point on the clutch until you light the second bulb. 6000rpm and 10 psi arent bad starting points, but really you will have to go through trial and error making adjustments. I guess with the launch rpm and boost start off with it spinning and keep dropping it down till you are just barely hooking up. we all know spinning aint winning, but its also not breaking **** as you would from dead hooking with no preload. good luck and have fun

 

Thanks man!! Looking forward to it.

 

I'd start high on the tire pressure (~14psi) and see what the track looks like when you get there.

You want the highest tire pressure you can run with the lowest 60ft. If you keep dropping pressure past that point, the 60ft will stay the same and the ET/MPH will start dropping as the tires end up sucking up friction.

See what it does at 14, then drop them to 12, then drop them to 10 if you picked up a fair amount on the 60ft from 14 to 12.

If the track is garbage, you may even get the best 60ft as low as 8psi.

Don't forget to bring an air pump or make sure the track has one if you dropped pressure and you didn't gain anything

 

Hey man thanks! I will play around and see what works best.

 

I would also run higher pressures. You're running drag radials which like a higher tire pressure than a slick does.

I'd start around 16psi or so and drop from there.

 

So how did you make out?

 

Well not so good. I ended up first pass breaking an axle spline inside my diff. Waiting for my new upsgraded axles and going for another shot!!

 

I would highly recommend some slicks for the track. You'll go faster and they're easier on the drivetrain than drag radials.

 

I highly agree with this statement. Wheel hop is hard to avoid with radials and it tears your drive train to pieces.

 

I am running Mickey Thompson ET street R's. I had the psi dropped down to 12. I'm making 430whp... I was also on stock axles...

 

slicks are the way to go and at least you will see what your car is truly capable of.

 

^^^^^^^^^^^^

 

I agree with everyone on the slicks. Wheel hop will destroy axles and other drive train parts. Drag radials have a harder sidewall and absorbs no shock. Slicks have a soft sidewall (wrinkle wall) that absorbs a lot of shock on launch, plus it will give a slight sling shot effect off the line.
But the main thing is, you will not get the best times you can on drag radials, your car will shine and do what it should with slicks. And I don't know if you're concerned that 430whp is too low for slicks or stock axles are to weak for slicks, I could be wrong but it seems that way based off the above quote, but I was using slicks back when I was only making 270whp. And when I got to 400hp I still ran slicks and ran pretty decent times. And if the concern is the stock axles, preload. Preloading is everything. I got my best time and 60' this year with a really good preload. and it reduces shock loads to save parts. Doesn't matter if you're on stock axles or upgraded axles, preloading is extremely important.

 

While i cannot deny that slicks are the way to go, radials are not a definite death sentence for ur drive train. I have hundreds of radial passes over the years and never broke a axle. Pre load and start a bit higher rpm were important factors in that. Either way its racing and all kinds of **** can happen. What kind of differential was that? Once u get the new axles u will be ready to rock and roll again!

 

agreed, it isn't a definite death sentence. It really does come down to the driver. If you can avoid the wheel hop, then Im sure you'll be fine. In theory the radials should be better on the drive train since they do not grip as hard as slicks, more spinning. So preload, mess with rpms, tire pressure and get it where it shines.

 

I need to get myself into drag racing the idea of driving as fast as you can in a straight line, your hearts must pump

 

Sarcasm?

 

MT ET Street R's are not slicks. they are a DOT drag radial, with semi-stiff sidewall in order to make them safe for driving on the street, aka taking actual turns and not shredding the tires to pieces. The softer the sidewall, the more flex the tire will have. the more flex the tire has, the less prone the drivetrain will be to failure, and the more traction you'll have, and the more consistent your times and traction will be. Hence why everyone is suggesting slicks, aka wrinklewalls, aka the softest sidewall money can buy
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