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Tim Dugan
05-26-2008, 07:32 PM
I'm lookin to find out what people are runnin for spring rates on a 85 VW GTI and what people are usin for sway bars front to rear all imput is good my car is very neutral right now. and any other info as far as set up is welcome too! ( no camber plates as of yet to be added soo!!!) Second order of business thanks to Baren & Anthony I had a great time at the PDX on monday The tires were a god send. :eclipsee_steering::eclipsee_steering:

markw
06-17-2008, 04:33 PM
Sorry no one has replied. Most racers are not using sway bars on the front, only the rear. A sway bar attempts to control body roll by pulling the unloaded tire up into the fender. This has the affect of leveling the car out. Not good for racing. The challenge with a fwd car is to eliminate the understeer or push designed in by the original engineers for safety. You control oversteer and understeer by tightening or loosening the front or rear. If you stiff the rear of your vw, you will remove the understeer. Some stiffen the tar out of the rear, I prefer a more neutral car specially on cold tires on the start of a race. Since no one has offered a suggestion, start with 550 pound springs in the front 400 pound springs in the rear. Put a tie rap around the shock struts, the shinny part and set the ride height. Go out and do a couple laps, but stay on the track. This will move the tie raps up, giving you an idea of how much shock compression you are getting. Shoot for an inch and a half. Once you get the hang of driving with your new spring rate, get some additional springs and make big adjustments one end at a time. Drive the car and see how the handling is affected. To a degree, it will be driver preference. Coleman and Carrera sell racing spring sleeve kits fairly cheap to convert your stock shocks into adjustable ride height. Don't lower the car too much. You can move the roll center too low. Lower the car, but try and keep your front control arms level or a little above level. Think of the tire moving up and down through an arc. The other choice would be to contact someone going fast with a VW that sells parts and take their recommendation as a starting point. You can then fart around trying different things. If you watch nascar, when they go up and down on tire pressures, they are in affect changing spring rates. Once you get a car balanced, slight changes can make big differences.

shwah
06-17-2008, 05:59 PM
I run 550 f, 550 r, stock GLI front bar, big aftermarket rear bar and Ground Control AD shocks.

When you add the camber plates, install them further back for more caster, which gives more camber gain when you turn the wheel, and more stability in straight line.

I have crappy poly bushings in 'donut' postion of the control arm, simply because I have not finished spherical bearings yet. Have delerin in the front of the control arm, and delerin in the front cross member bushings, and delerin in the rear beam bushings (yeah these 'should' be spherical, but this adds roll stifness).

The car handles pretty well for my driving style with a spool.

Beran
06-17-2008, 10:44 PM
Tim - I will share what we had for a springs - I just need to look it up. Send me an email and I will email you back with them. The ones above seem right.
No bar up front and a race Shine bar in the back.
Level control arms up front - even to a little lower in rear ride height then front.
1/16 to 1/8 to toe out in front and zero to a little out in rear depending upon track. NHMS you try to run a little toe out on the right side rear and left side at zero. I run zero to just a hair out in the rear at Lime Rock.
You will need camber adjustment soon especially at NHMS. You can loosen the upright & strut and push it in as much as possible so you get as much as you can but you will need adjusters eventually.
Hoosiers - start cold (begining of day) at 28-29 PSI all the way around... maybe one pound more in the rear corner that get the less use (left rear @ NHMS). Not positive about the PSI for you since you have a softer setup.

Beran
beran(at)beranpeter(dot)com

Bildon
06-17-2008, 11:18 PM
500/400 always worked well as an "all track compromise". You can of course go stiffer on smooth tracks and with some of todays' higher tech shocks. I second all the other advice here on bars, toe and camber etc.

Note: This has been discussed 100+ times here... Give the forum search a try. Lots of info.

Sandro
07-08-2008, 11:01 PM
Note: This has been discussed 100+ times here... Give the forum search a try. Lots of info.

hint: when it comes to vw's especially suspension I search the topic and put bildon as the user, you would be amazed at the info he has poured out over the years regarding car setup, its almost like cheating (just this weekend I solved a rear tire problem based on some of his advice)

:happy204: for Bill