Need help with airbar install

[ragtop1968rs]

I'm installing an airbar in my 68 camaro. I have the cradle in and the lower bars in. I do not have the coilovers or the upper bars in yet. I have the car in the air and leveled. I'm measuring for the pinion angle vertically on the rear end yoke and getting 89.5*. The rear is centered perfect side to side. The problem is it is not centered in the wheel wells front to back. On the drivers side I've got 1 1/2" in the front and 2 7/8" in back. On pass side, 1 5/8" in front and 3" in back. So it's 1 3/8" difference on each side. Since the lower bars are not adjustable, I'm not quite sure how to correct this or if I can at all. Any ideas? Thanks, John

[marolf101x]

So long as the cradle is in straight you DO NOT want two different bar lengths. Different bar lengths would provide different geometry on both sides of the car, which could make it very unsafe to drive.

Typically we find that "non centered" rears are the result of quarter panel replacement. In these cases there are only two options:
1-cut the quarters out and put new ones in where they should be
2-use adjustable bars and split the difference between each side (keeping the bars the same length).

[bret]

Out of the thousands of Camaro suspensions we've done, I've seen this on maybe 5-6 cars in the last 12 years, with no particular pattern as to why, nor any consistancy between model year. The cradle/rearend is not crooked in the car, just too far forward by about an inch. The solution to this point has been to build a 1" longer set of bars. Rodney at our shop can lead you through this no cost change. [email protected].

We have seen several where a quarter panel has been changed and, depending on other damage or the talent of the installer, you end up with a 1/2" to 3/4" difference in gap from one side to the other. In that case, you can usually split the difference to reduce the gap variation to around 1/4".
Or change the quarter panel.

[onair]

John,
One thing I noticed in your post is your pinion angle. The pinion should be on the same plane as the engine and trasmission to get ujoint cancelation. It is generally right around 3 degrees, so your pinion would be 3 degrees up. The way the kit is designed, the lower bar bolt is down below the axle tube, so when you set the pinion angle up it will rotate the rearend on the lower bar bolt and move the rearend back in the opening. This should center it in the opening.

[ragtop1968rs]

I rotated the rearend up to set the pinion angle at 2.5 degrees. The tires are within about a half inch front to back now. I can live with that. Thanks