-69 Corvette front suspension [Archive]

Olav

05-20-2009, 12:09 PM

I friend of mine has a 69 corvette with BB 427 cid. Totally rebuilt supension with these parts: VP&B fully adjustable suspension system includes tubular A Arms, Bilstein performance shocks, mono fiberglass spring Car has 9.5*20" wheels in front with ZL1 flares. The car is very unstable and it's "tracking" all over the road. Is it the wide front wheels or the alignment thats the problem ? We dont have any alignment spec for the work done on the car so we don't know what it should be with this suspension setup. The stock specs I belive is not suited for this suspension setup.

Thanks!

Olav

ErikLS2

05-20-2009, 12:55 PM

I have a few thoughts based on the info you've provided. First is if possible I would try a more stock tire and wheel size and see if it behaves the same. A tire that wide with most likely a very low profile may be following an imperfect road surface, even if you can't see any imperfections in it. Secondly, see if the toe in is way off, you can get a close idea with a tape measure. Beyond that, I would like to see the alignment readings.

Lowend

05-20-2009, 05:18 PM

I would guess the car has a bad alignment and a bunch of bumpsteer. Start off by going to the alignment shop

Olav

05-20-2009, 11:57 PM

Thanks!
Any recomandations for alignment data/spec.
Bumpsteer wil not be easy to compensate other than raise the car again.

MonzaRacer

05-21-2009, 05:56 AM

OK for a try since its all changed try to shoot for as much negative caster as possible say around +4.0 degrees on left and +4.5 degrees on right the split allows it to climb the road crown, set your camber around -0.25 to -0.50
And with the wide tire I would try for 1/16" to 1/8" in toe. This is just a educated guess, Ill try to look up Actual spec for the car tonite. But this will get it close I feel, and I have only done alignments for over 20yrs.
Oh yeah, when they want tolerances have them simply plug in 0.25 +/- on caster and camber and 1/32 +/- if you dont hear back and still need specs pm me.

Skip Fix

05-21-2009, 06:40 AM

I think you meant positive caster since you have the + sign and that helps them track straighter.

Lowend

05-21-2009, 09:51 AM

you can adjust bumpsteer - you just need a shimable tie rod like the Baer Tracker setup

Olav

05-21-2009, 10:15 AM

OK for a try since its all changed try to shoot for as much negative caster as possible say around +4.0 degrees on left and +4.5 degrees on right the split allows it to climb the road crown, set your camber around -0.25 to -0.50
And with the wide tire I would try for 1/16" to 1/8" in toe. This is just a educated guess, Ill try to look up Actual spec for the car tonite. But this will get it close I feel, and I have only done alignments for over 20yrs.
Oh yeah, when they want tolerances have them simply plug in 0.25 +/- on caster and camber and 1/32 +/- if you dont hear back and still need specs pm me.

Thanks!

parsonsj

05-21-2009, 10:37 AM

Once you check all that out, let us know how much wheel offset you've got. Lots 'o dish?

jp

WS6

05-21-2009, 05:01 PM

get in touch with VB&P about what alignment setting to go with. They will have them on hand and can tell you.

MonzaRacer

05-21-2009, 09:43 PM

Yes I meant positive caster, sorry.

Olav

05-21-2009, 11:56 PM

get in touch with VB&P about what alignment setting to go with. They will have them on hand and can tell you.

I will send them e-mail for the spec.

Olav

Olav

05-22-2009, 09:18 AM

Got answer from they. They refer to catalogue : http://www.vbandp.com/Our%20Catalog/source/page_54.htm

MonzaRacer pls take a look, any comments ?

Olav