andrewb70

You definitely do not want squat. When the rear of a car squats, what is actually happening is that the forces of the launch are actually trying to pull the rear tires UP. This in turn causes the body to squat down over the tires. This is the reason why the FC stock suspension is not ideal for drag racing. When drag suspension is set up properly, the body will actuall lift a little in the rear. This is the result of the suspension pushing the rear tires down and causing the body to move up.
Check out these videos:
http://68.178.140.70/videos/06-08-09-013.wmv
http://68.178.140.70/videos/06-08-09-001.wmv
Please ignore the pistonvsrotor thing. I am not starting anything. This discussion is about suspension.
The first video the 60 foot time is 1.18 and the second is 1.27. That car leaves incredibly hard without any squat. I think you should have your 4 link checked out by a good chassis guy again.

Andrew

LUPE

I had my 4 link checked out a few weeks ago when I had the allignment done. The only thing they didn't check was the pinion angle.

These are the things I'm going to change before tuesday.

1. I'm going to measure and set the pinion angle tommorow. I plan on setting the pinion angle at 4 degrees downward.

2. Drop my tire pressure down to 9psi to start out with.

3. Set my front shocks on the softest setting and loosen up my rear shocks as well.

4. Turn 2 step back on

Hopefully, I can smash some tire to the pavement.

13B-RX3

iTrader: (2)

Good luck Eric, keep us posted!

tcb100

Now that i think about it, Andrew b70 is right. I ran non-adjustable bilsteins on the rear and tokicos full soft up front. I would still be wary of such low pressures without tubes though.

silvr94r2

iTrader: (3)

+1

AZ'sFastFD3S

dude I dont know why you keep thinking its tire pressure. I run 18 psi in my ET STREETS. The 1000=HP Supras I know run about 16. Do not run 6psi, It will be very scary. See my FD in this vid transfer the weight back. I am runnning Bilstien struts and grex springs nothin special. They are just soft. This is a very low boost pass...........

http://members.***.net/trevmov3/7s.wmv

1RevvinFC3S

Stiffen right rear shock, soften left rear. That should help with your launches significantly.

LUPE

Well, I just got done working on it.

Here is how the car was setup:

Front shocks were set to the stiffest setting. Rear shocks were already set to soft. Drive shaft angle was 2 degrees downward, diff was set at 7 degrees downward so that means the pinion angle is 5 degress correct?

I made some adjustments and dropped the pinion angle to 4 degrees downward (My control arms are small diameter afco tubing so I expect small amounts of flex).

I loosened up the front shocks all the way and left the rear shocks loose as well. The front of my car sat lower than the rear of my car so I raised the front of my car up .75 inch so that the weight would transfer better.

I plan on dropping the tire pressure to 9psi to start with and work from there.

What do you guys think?

Thanks again !

silvr94r2

iTrader: (3)

I don't agree with the rear being set to it's softest setting but if you want to start there then go ahead. And i hope you get your front end aligned again after raising it up.....if i'm not mistaken that will affect your alignment?

Don't waste the whole night without trying something different. If it ain't working try and figure out what it is and make a change while at the track. That's the only way you'll get a handle on it.

Everything else sounds like a plan so go with it and "git er dun"!

GOOD LUCK and HAVE FUN!!!

13B-RX3

iTrader: (2)

Start with a little higher tire pressure and go from there IMO. If the pressure is too high it just spins but if it is too low it will skate around on the big end. Also if your rims aren't screwed i would not run less than 10 PSI.

LUPE

Even with the rear set soft, it doesn't feel as soft as the front. The rear still feels pretty stiff when I push down on it.

I don't have time to get another allignment but I'm sure it didn't change it very much. It might have moved the camber but not the toe. Camber shouldn't hurt too much I wouldn't think right?

I wish I could get some actual racers to go help out, all my friends are a bunch of drunks.

1RevvinFC3S

Try what I said. From watching the vid, I could see the way it was leaving the hole and what it was doing with each shift. Just try what I recommended and if that doesn't work, well you can call me an idiot.

mcfly

we have a guy up here in canada with a chevy truck.
he has anywhere from 1190(street hp) to 1700 on race gas and smaller pully.

When iwas talking to him he was saying he runs 6 psi in his rear tires.
taking into account that they are 18" wide on a 15" wide rim and sportman tires i do not know how it affects a mt street.

he also had bead locking though

crispeed

What rear spring and shock setup are you using in the rear?
Coil spring rate is most important?

LUPE

I'm using the Eibach springs in front and back which are rated at like 580 lbs. I know they're too stiff, don't I need something like 180 lb springs?

I'm using the Tokiko 5 Way Adjustables.

crispeed

Eibach springs going by the weight of your car are too stiff for your setup especially the rears. With IRS you have to use stiffer springs to combat sqat. With a solid rear it's different. On my car which came right in at 2600lbs I was using 150lbs in the rear. I know you scaled the car so what was the weight on the rear wheels?