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camaroracer1992
10-02-2008, 02:20 PM
what would make my car hook good, but then about 10ft out of the hole it looses traction? I would like to get this hammered down so i can spray a 175-200 shot out of the hole.


car has all spohn rear end with rod links, -2 pinion angle, and also a x-duty sway bar.

28 x 11.50 slicks with a good burn at 16.5 psi

mc73nova
10-02-2008, 03:06 PM
what kind of shocks do do you have in the rear? I usually run 11-12lbs in my slicks.

Pro90rscam
10-02-2008, 03:12 PM
I would try getting rid of those girlie tires and put some real rubber back there by tubbing it. Then that bitch will hook!:nod: HAHAHA!!!!!!

mc73nova
10-02-2008, 03:26 PM
That tire should be more than enough. I 60' 1.40 on a 9" and have been 10.52@127.

1984camaroz28
10-02-2008, 07:24 PM
what shocks are in the car. drop the psi down to 13.5

camaroracer1992
10-02-2008, 09:01 PM
BMR tubular front suspension with coil overs and lakewood 90/10 struts

rear is all spohn with lakewood 50/50's with stock springs

Pampered-Z
10-02-2008, 09:22 PM
If you can get a vid of the car launching and watch if the rear is unloading/rocking too much forward.

Try going -3 on the pinion, just to rule out some odd deflection if the angle goes to 0?

Somewhat common is that after the inital hit and the rear squats that as the shocks rebound it can rock back forward causing the rear to unload. if so put air bags in the springs and work with the pressure.

79CamaroDiva
10-02-2008, 09:31 PM
If you can get a vid of the car launching and watch if the rear is unloading/rocking too much forward.

Try going -3 on the pinion, just to rule out some odd deflection if the angle goes to 0?

Somewhat common is that after the inital hit and the rear squats that as the shocks rebound it can rock back forward causing the rear to unload. if so put air bags in the springs and work with the pressure.

listen to him. also, how far up are the wheels coming up? is it unloading when the wheels hit the ground? how old are the tires? definitely drop the psi down some.

also, very important, and you probably know, but only change ONE thing at a time. If you change too much and it still doesn;t work, you won't know if one thing would have fixed it and the other made it worse.

camaroracer1992
10-02-2008, 09:31 PM
i aways though that airbags hurt torque arm suspension launches?

NJSPEEDER
10-03-2008, 05:57 AM
I would try getting rid of those girlie tires and put some real rubber back there by tubbing it. Then that bitch will hook!:nod: HAHAHA!!!!!!

Why don't you just trade him since that pop gun under your hood can't spin tires in snow. lol :rofl:

NJSPEEDER
10-03-2008, 11:21 AM
Two questions:

Are you lifting the fronts at the hit?
What are your front and rear suspension packages?

If the front tires are coming up, you may be getting something similar to limiter bounce. Time to put on your high school physics hat.

When the front tires come up, the front suspension drops down. Now remember, every action has an equal but opposite reaction, so when the front suspension "bounces" to a stop, it actually pulls load off of the rear tires.

Switching to lower rate, longer front springs, and front shocks with more travel can help with this kind of unloading.

-Tim

camaroracer1992
10-03-2008, 02:22 PM
suspension mods are already listed above.

tires are barely coming off (like an inch)

NJ Torque
10-03-2008, 02:38 PM
I had this happen to me.. turned out a broken sway bar bolt.

Pampered-Z
10-03-2008, 09:50 PM
i aways though that airbags hurt torque arm suspension launches?

Your not going to be putting in so much air that it's going to raise the car or change the angle ( that is a common mistake ), you want just enough that it stiffens up the rear so the shocks don't compress down too far causing the suspensions angles to change drastically or that when the shocks uncompresses it pushes all the weight back onto the front tires.

NJSPEEDER
10-04-2008, 11:12 AM
Get a softer spring in the rear, like a stock V6 spring. Should let it sit and stay down better.

12secondv6
10-04-2008, 07:28 PM
When I was spraying off the line and had the rear QA1's set to all loose this was happening.

As I tightened them up this gradually became less.

I ended up having the right rear shock set one less than the left rear and much better.

Lots of trial and error

heavy_chevy29
10-05-2008, 12:59 PM
i feel your pain man. i get consistant low 1.7 60s using the footbrake. forget about using the trans brake. i get mid 1.8s with the transbrake.

JSPERFORMANCE
10-06-2008, 07:09 PM
First off tire pressure is too high.

What is the weight bias of your car?

Spring rates front and rear?

SteveR
10-07-2008, 12:59 AM
Get a softer spring in the rear, like a stock V6 spring. Should let it sit and stay down better.

QFT, and drop the pressure a little. Just make sure you have the wheel well clearance as the softer springs will allow the rear to squat more.

TEKHAWK
08-13-2009, 06:52 PM
about 10ft out of the hole it looses traction

Tighten the rear shocks. Loosen up the front.

JerzLT1
08-13-2009, 07:22 PM
holy year old post!!!