63 340HP

I am retiring the factory 63 rear camber bracket and rods to the restoration box and have a new VBP smart strut kit to install. I am looking for tips on where to set the camber and the camber gain.

The 63 bracket has a 10 degree difference between the half shaft and the strut rod. When the axle is level the rod is ten degrees down on the hub end. This produces about five degrees of camber gain in the usable wheel travel. The result is camber gain almost like the front of a twin I-beam truck, with the tire tread on the shoulder corner almost all the time (not good for traction).

The VBP kit uses the better C3 bracket geometry and allows the inboard end of the strut rod to be adjusted in elevation, using vertical bracket slots to change the camber gain. I searched and read the zero to one degree negative static camber suggestions, but the more descriptive camber gain recommendations appeared to be more to fit the tires (camber in to tuck the tire under the fender lip) rather than to improve handling.

The focused question is what camber gain will benefit the handling? Flat (minimal camber gain) for drag racing makes sense, but for a cornering car what is recommended?

Should the lack of a rear anti-sway bar (like my 63) alter the final settings?

I'll be running 225/60/15 tires on 15x7x4.25 backspace (0.25" offset) rallye rims. These fit way inside on the drum brake cars as there is no parking brake bracket on the outside of the trailing arm to hit.

Thanks for the guidance.

Crazyhorse

Here's some recommendations from thier site......

http://www.vbandp.com/instructions/h...ruct/align.htm

And here's an archived thread that may also interest you....

http://forums.corvetteforum.com/show....php?t=1106026

63 340HP

Thanks for the response.

The linked alignment thread is what had me worried (that one, and a few from the C3 forums).

My search resulted in the Herb Adams catalog as well (the reference sighted in the thread) but there is no recommendation to adjust or set the rear camber gain. This lack of reference is most likely due to there not being a method to adjust the camber gain with the stock camber rod bracket when the guide was printed. The adjustable pin height bracket is newer than the printing of the article. VBP did send a few specs with the bracket but I was hoping for some user feedback.

I read the guidance to shim-in as much front caster as bearable (~2 degrees positive with manual steering) and exploit as much front negative camber gain as possible to compensate for the chassis lean, so the front is fairly limited in what we can change (all except for JohnZ's tip to align the front with known shim stacks at near-zero camber for street, and with a preset extra set of track shims that increase the camber when installed -- great tip!).

This brings me back to the rear camber gain. Should it mirror the front gain, or is there a better camber curve to target that better compensates for the chassis lean? I can carry an angle finder and change the rear camber strut rod length as easily as changing the front camber shims (change the static camber) but is the inboard rod pin height something best set and locked, or should it also be adjusted for different tasks (to change the camber gain for street or track)?

I can live with chassis lean angle knowing my 63's single 3/4 front anti-sway bar will never keep the chassis flat like the aftermarket 1.250/0.75 Autocross bars (even with ~500/360# springs). The Sting Ray's chassis lean is a lot less radical than some of the off-road endurance race buggys and trucks I have driven. I just want to exploit what I can alter without drilling to run a rear bar (or making the ride too harsh).

Thanks (again) for the link help.

63 340HP

I have installed the bracket and struts, and they work as advertised. I can set the camber for zero camber change through the travel or set for a camber increase during bump or lean. I still do not know what works best, recommendations are still welcome, but the process has me looking at other things (project creep).

Are there parallel areas of the frame than can be used to square the rear toe and thrust angle (areas to measure from for accurate rear toe-in respective to the frame)? The Adams book has the sight down the rocker panel method, but I do not trust my 63 rockers to be square. If I need to decrease the toe on one side do I just swap shims from inside to outside at the trailing arm bolt (or do I have it backwards)?

I also have a casting number question, with the rear pumpkin in my 63 having a "L 8 2" cast on the drivers side above the strut rod bracket. Is this Dec 8 1962? The stamped numbers are "CE5 17 63" dating the gear assembly a few weeks before the car assembly date, but the 62 date would make it the oldest casting on the car. Did they batch the pumpkin castings for the early C2's?

BTW, does anyone know what the "AAC" stamp refers to on my original 63 strut rod bracket?

C2BOB

I bought a set of the "smart" struts and the poly bushing were junk (worn and sloppy) in under 5,000 miles. I called them and they said the bushing must have been defective but wouldn't warranty them. I bought their replacement bushings, checked the material and hardness and found it to be exactly the same. Bushings went into the trash and stock C3 bushings went into the struts (I do like the adjustability). Good luck with their poly bushings.

JohnZ

Inventory control wasn't a strong point in those days - the casting date (December 8, '62) is probably legit. "AAC" is the vendor's identification code.