airbar 4 link on '69 bird trailing arm issues
 

OK here's my first dumba## question. Currently fabbing the chassis for my firebird(yes I have been working on it, and pictures are coming shortly). Fitting the airbar w/ coilovers using stock 10 bolt/ multileaf BOP axle. Has anyone run into trailing arm length issues? The lowers seem to be about 1 inch short, and I need to keep the tire centered in the wheelwell, first looks, secondly I already had my aluminum driveshaft built last fall. i know it's a bit of cart before the horse, but I think you all know how projects and designs evolve before they are completed. Any thoughts on replacement? Do heims last very well on the street? I could fab up new control arms. suggestions please. Car never driven daily and if I get 1000 miles a year it would be a record. I am thinking of actually running this car at the track for enjoyment only.

Is your pinion anlge set correctly? That will affect the center line of your axle more than you think.

Yes, it does change things. Today I finished fitting the rearend up and I can get it to fit, but I have 6 degrees upward pinion angle. To make matters worse, my rearend is higher than my tailshaft, increasing u-joint angle to around nine degrees. I don't think it will last too long. Now I must look at changing the engine angle, and still lose 3-4 degrees pinion.

Been there done that man. If you can get 4 degrees negative driveline angle and 3.5 positive pinion you should be close to center. Mine is almost perfect but it's a 69 Camaro. If you are low like me then it may be best to cut the tunnel now. I don't have driveline vibrations but if I had it all to do over again I would cut the tunnell and run 2-3 degrees of driveline angle.

Thanks for the info, i'll try to persuade the motor/tranny up a bit, and most likely lengthen the trailing arms. Thought I was done welding the floor, maybe not. It's all apart now, so I'd be dumb not to do it the right way now.