Removing sport shims

[Nadine UK GTS]

Went to take my sport shims out (track use) and...the two nuts clamping the sport shims in-between pivot bar and frame, do I do them back up tight after removing shims, or just tighten them back up to where they were when shims were in? (Sorry if this is a stupid question!)

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[Brad Manhattan Beach]

Nadine:

I'm no suspension expert here, but I don't think it's as easy as removing the shims and you're done. I think that most would recommend that you re-align your car after you do this with the race alignment specs. I would call Dan Cragin to confirm this. I would hate for you to hit the track, and find out after the fact that you should have done something that would have prevented an expensive mistake.

Good luck and have a great weekend.

Brad
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Nadine UK GTS:
Went to take my sport shims out (track use) and...the two nuts clamping the sport shims in-between pivot bar and frame, do I do them back up tight after removing shims, or just tighten them back up to where they were when shims were in? (Sorry if this is a stupid question!)

You must be registered for see images

<HR></BLOCKQUOTE>

 

[kverges]

Sport Shim 101 (according to me, anyway)

1. Loosen nuts holding upper control arm pivot shaft enough to remove sport shims.

2. Remove shims.

3. Tighten nuts securely, which will pull pivot shaft against upper frame rail.

4. Replace wheel and drive the car like stink.

5. Reverse the above for street use.

This procedure will give you something like a degree (negative) of extra front camber and some toe out, which will reduce understeer and improve turn-in. Neither are optimum for street driving (i.e. tire wear and smooth tracking), but for the track you do not need to re-align the car, assuming the alignement was satisfactory in teh first place.

FWIW, I also think the rear needs more camber and toe on track and the above may cause your car to oversteer, but since it is free to do the above, try that for starters before you get too fancy with alignment.

FWIW

Keith

Cars with stuff done to them, but not the same stuff as FRANK

 

[pauls]

Have you driven your car at the track with this set up? Autocross maybe, but roadcourses need to take some of the toe generated from removing shimms back out.

 

[GTS Dean]

The additional toe-out is not intolerable, but you have to expect some additional twichiness at high speed on straights.

Last fall at TWS, I ran like 3/16" toe out in the front at up to 142 mph. Upon reflection, it was a bit much, but it sure helped get through the slow, twisty bits.

If you want, you can screw the toe link rods 1/2 turn clockwise to pull the tires in just a bit.

Viper-specific note:

All the toe links are right hand thread. Screwing them clockwise up front _decreases toe out_. Turning clockwise at the rear _increases toe out_ (NOT the hot setup).


P.S. - Tightening the nuts on the front pivot bar is much easier with a ratcheting box end wrench.

 

[Nadine UK GTS]

Thanks, I'll look forwards to having a 'play' with your advice when I've got my exhaust sorted!