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Originally Posted by nitrorocket
The rear suspension is good to go, except for sway bar selection. The front is stock except for the poly bushings. I notice a lot of understeer with the setup I have now in high speed sweepers. I thought B body spindles helped camber and you could get bumpsteer spacers??
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With springs in the weight ranges I suggested a rear sway bar should not be required at except as a tuning aid to dial in a little more oversteer (aka: driver preference.) I run no rear bar and the rear drifts ever so slightly with my setup which is exactly what I wanted.
Given the stock way of mounting a rear sway bar to an A-body the swaybar effectiveness is marginal at best which is why I prefer to tune the rear with springs rather than a bar. If it comes down to needing a rear bar a MUCH better way to do it would be to retrofit a 3rd gen F-body sway bar setup on the car, where the bar swivels on bushings attached to the axle tube then there are hard uplinks going to the frame.
My setup is as follows:
Front: B-body spindles, alignment specs of +5.5 caster / -1.0 camber / 0 toe, 1.125" sway bar, 750# springs (going to 900 or 950# when I change the spindles.) 255/45/17 tires on 9.5" wheels. The car does pull a little bit to the right on the street because I have no cross caster to compensate for road crown. Doesn't bug me, don't have any cross camber or caster in my daily driver either.
Rear: GW TBC-4 lowers, Edelbrock uppers with rubber in the rear end ears, Hypercoil 175# springs. 285/40 tires on 11" wheels.
Shocks all around are Edelbrock IAS which have better rebound control than most in the price range, but still aren't ideal. I am looking at picking up some single adjustable Varishocks from a friend who is a WD for them.
Given the weight of an A-body I chose tires that would end up being installed on the widest wheels recommended by the mfg to minimize sidewall deflection/squirm. I may try a 275/40 & 315/35 setup next time to see if the additional rubber (theoretically more overall grip) outweighs negatives of additional sidewall squirm (theoretically less turn-in feel) compared to the current setup.
As far as the stock front suspension... no wonder you're pushing! The stock suspension has terrible camber gain properties-- in fact, it's reversed! It goes positive on compression. Bump steer is so-so and the roll center is too low. It has everything designed in backwards to what you want in a performance app, but is perfectly safe for grandma (i.e. it pushes really, really badly!)
B-body spindles help raise the roll center a bit and change the FVSA to give better camber gain but they also slow the steering ratio, screw up ackermann, and dramatically increase the bump steer. For a long time it was the "hot ticket" simply because there were no other alternatives short of custom, but now there are lots better options... SC&C stage 2 with stock spindles, ATS spindles, or the "Denny" setup with the Coleman spindles, although with the Colemans and their pin drop that setup is best utilized on very low ride heights. I believe the Coleman setup is better than the AFX setup geometry wise by a hair (and I mean a tiny, tiny bit) but for more "street friendly" ride heights the AFX has the advantage because it puts the control arms in a more favorable spot for lateral scrub because the AFX spindles have less pin drop. If used at the more street friendly ride height the Coleman setup puts the control arms at a slightly less favorable angle. If you don't mind your front X-member about 2.5" off the pavement with 25.7" tall tires then the Coleman setup is pretty badass... at least with stock control arm locations and lengths. Getting much better than the AFX or Coleman setup would likely require custom control arms and revised mounting locations.