G-body LS1 rear brake clearance

[BigBlockOlds]

Anyone else have an issue with clearance between your LS1 rear brakes and notched frame on a G-body?

I had to cut apart my watts link to redesign how it attaches just so that it would clear the bleeder screws. Stinks when you find a clearance issue AFTER you've already had it powder coated. :(

So I managed to get the watts link to clear, but if I jack the rear end up to my desired ride height (see picture below), it end up with the bleeder screws almost hitting the frame during suspension travel. I probably have a 1/4"-1/2" clearance between them and the face of the frame.

https://static1.pt-content.com/images/pt/2009/07/IMG_1321-1.jpg

Being that the watts link isn't supposed to let the rear end move much at all side to side, I'm not too worried about that. My concern is how the brakes react when you step on the peddle. With brand new pads, I imagine the caliper won't move much at all but with worn pads, I'm worried its going to hit.

Anyone know how much a typical disc caliper will move when applying the brakes?

Thanks for the help,

*EDIT* Upon further inspection, I don't have the 1/4"-1/2" clearance I thought. Its more like nothing at all. It appears that the actual bleeder screw is missing the frame but the rubber cap is just barely kissing it. I guess my only option is to install a bump stop between the rearend axle tube and frame somehow.

[T-CHRGD]

Could you please post a pic of the rear caliper / frame ?? Thanks.

[BigBlockOlds]

https://static1.pt-content.com/images/pt/2009/07/IMG_1329-1.jpg

https://static1.pt-content.com/images/pt/2009/07/IMG_1331-1.jpg

https://static1.pt-content.com/images/pt/2009/07/IMG_1333-1.jpg

I just went ahead and notched the frame a tad to clear (after these pics were taken). Works perfect now.

[jackfrost]

Andy - is your rear the same width as a stock g-body rear?

[jackfrost]

also, could you fit a 90* fitting in there and then put the bleeder in pointing up?

[BigBlockOlds]

Yeah, the rear is stock width. If I had it to do over again and new I was going to be using the LS1 brakes, I would have had them make the rear about an 1" wider.

I thought about the 90* fitting but then I don't know how you would get the bleeder to seal. I believe the taper on the end of the bleeder screw is what seals inside the caliper to keep fluid from escaping. You'd almost have to have something custom machined.

Someone on www.montecarloss.com posted a link to some aftermarket calipers that might work assuming they would bolt up to the LS1 brackets. They have the bleeder screws coming into the side of the caliper, parallel with the frame rather than pointing straight at it.

I may have done this all for nothing anyway. I've been concerned with my where my ride height is going to be and want to make sure I have the "look" but when I was under the car the other day, I noticed my shocks were almost bottomed out at the ride height I wanted. I only had the top of the tire almost even with the fender lip which I didn't think was all that low. I'm just going to have to wait until I have all of the weight back in the car before I start messing with the ride height I guess.

[jackfrost]

hmmm... maybe you need different shocks. my car sat with the top of the tire almost even with the fender lip, and I had no problems.

[BigBlockOlds]

Yeah, thats what I was figuring. My brother's '81 is the same way and all he has is F-body rear cargo coils with one coil cut off and stock replacement Bilstein shocks.

I have the same F-body coil springs but I'm using the stock replacement QA1 single adjustable shocks which are the same height as the Bilsteins.

So something is up and I'm figuring it has to do with the weight of the vehicle. So I've stopped messing with the suspension and moved onto finishing the A/C system. I can't really torque any of the suspension down until I have the weight back in the car anyway.