69 leaf spring rear, how to raise end height?

[anguilla1980]

I have my new suspension and rear end installed in my 69 Firebird. This design has the axle OVER the leafs for those not familiar.

Right now my car sits PERFECTLY level, which I would be ok with, but my rear fender lips now have slight interference with the sidewall of the rear tires. I *could* roll the inside lip and be good, but to be honest, I want to raise the rear about 1". I really want a little bit of a stance to my car with the rear higher than the front.

Since the axle is over the leafs, I did not install the rubber pads between the axle tube and the shock plate. Am I right in thinking that adding the rubber would only move the axle up higher under the car, thus lowering the car? I went without so the car would be as high as possible.

That leaves me with having to go with longer shackles. I have the Global West Cat5 spherical bushings with their Del-A-Lum rear shackles. It seems they do not make a shackle frame that is simply 1" longer. But, it *looks* to me like I could use any outer shackle frame long as the bolts are the correct size and I'm sure to use the white nylon washers. Is that correct?

Thanks!

[68Formula]

Might get a 1/4" higher if you remove the rubber insulator pad from between the axle perch and top of spring. Then you'll have to compensate for the gap, by adding a 1/4 "lowering block" underneath the spring (sandwiched between the mounting bracket) as a spacer. (Otherwise the spring would be loose when the mounting bracket is flush against the perch.)

[anguilla1980]

I don't have any pads, on the top or bottom of the leaf. The axle from QP has the leaf mounts for a CalTracs setup (even though I'm not running one). It's not like the factory style perch at all.

So from the bottom up its: shock plate, leaf spring, then the axle and the axle mount sits flush on the top of the leaf on the dowel. There is a hole in the center of the shock plate that the bottom of the locating dowel goes through. So everything is nice and tight. I didn't want the flex of a rubber pad, plus I thought adding any would only serve to raise the axle higher into the car.

[ULTM8Z]

I think your only option is taller shackles. But to get 1" of height at the wheel would take nearly a 2" increase at the shackle.

If you have no pad between the axle and spring that's as far as you can go there.

[NOT A TA]

I think you'd need shackles with over a 2" increase to raise the body 1" over the wheel because the axle is forward of the middle of the spring.

[dhutton]

Time for different springs imho.

Don

[anguilla1980]

Thanks for the info guys. Maybe I should just leave my car perfectly level like it is and just roll my fender lip. I'm too worried adding 2" to the shackles may negatively affect the handling too much.

I just spent a bunch of money on these Hotchkis springs and having the Global West spherical bushing pressed and welded up, so no going back....

[68Formula]

What size tires are you trying to fit?

[anguilla1980]

255/50/17 on 17x9 rear (5.250" backspacing). They are the reproduction Rally II wheels from Restore A Muscle Car.

The probably would fit, except when the leafs articulate side to side due to the GW cat5 bushings AND I hit a bump in a turn, the middle of the sidewall is just every so BARELY contacting the inside lip. Not a big deal, I'll be rolling the lip this weekend.

The point if this thread was not to clear the tire, it was to gain that old school muscle car stance with the rear higher than the front. I'm not using the Hotchkis spacers under the front sprint isolators in their a-arms either so the front is already as low as it will go.

[indyjps]

Rearch springs. New springs. Add a leaf. Remove short leaf and add longer leaf. Lift blocks. Longer shackle.

Longer shackles will likely change your pinion angle. Any height addition will be counterintuitive to the GW cat 5 bushings.

You could change back to a poly, rubber, or solid spring bushing to prevent the tire rub, doesnt help with raised stance.

Swapping leaves - I "tuned" my leafs when I was drag racing to get it to launch hard and straight. Swapped leaf lengths and moved clamping points around. Its a lot of work but accomplished what i wanted. You can adjust height some, who knows what your spring rate will end up being though.

New springs is the most straightforward. Heavy truck shops can throw your springs in a press and rearch, results arent always predictable.