86 GLHS Braking Questions

[jckrieger]

I just put a new timing belt on the GLHS and advanced the timing a couple degrees. While on a test drive, I noticed the car doesn't stop terribly well... and never did. The pedal effort is quite hard, and it seems like the rear brakes aren't doing anything. Assuming the rear brake cylinders are seized (car has 30K miles), what kind of brake performance can I expect? Is it possible my rear brakes are working and the stock GLHS brakes just suck? Let me know how they're supposed to feel relative to say, an 11" brake Daytona/Spirit or a CSX.

-Clark

[86Shelby]

I can say that an '86 GLHS with freshly redone brakes, both front & rear stops great. My car had the minivan calipers & pads on it FWIW. The brakes before the rebuild & minivan calipers were just fine. I would say they were about equal to my R/T with 4 wheel disks considering the weight they are trying to stop. Shortly after doing the brake rebuild we did a 60- test and came in just over 100 ft.

My GLHT with crap rear brakes(siezed cylinders & fried shoes) and warped front rotors stops like warmed-over-refried azz. Yes it sucks. Just going through the rear brakes and adjusting everything real nice does wonders for them.

[jckrieger]

That's encouraging. The previous owner put new Bendix front rotors, pads, and calipers on the car and got discouraged when it didn't help the car's braking. He also purchased new rear drums, shoes, and hardware but never installed them. I'll tear the rear brakes apart tomorrow and see if I can get the car to stop again. I was a little worried since it seems like everyone with an L body is doing brake upgrades!

[tryingbe]

Minivan calipers upgrade and 10 inch rear disc upgrade are great.

[black86glhs]

I just replaced the front rotors on mine. The caliper pins were expanded(rusted) on the driver's side. They weren't frozen, but you could tell it was causing the pads to wear more. The brakes were over 8 yrs old that I just replaced. The new rotors and pads made a big difference in feel. I don't have to stand on the brakes to make a simple stop. Getting the rears working will make a big improvement on yours.

[86Shelby]

Turn the drums, rebuild or replace the wheel cylinders and adjust them accodingly and they should make a world of difference. Remember that the right adjustment for the rear is that when you are turning the drum you hear a real light sshhh, sshhh, sshhh. Sometimes you need to press the brake pedal during it to center the shoes & everything during the adjustment.

[jckrieger]

Today I took the rear brakes apart (fronts have new calipers, rotors, and pads). I found both rear cylinders were stuck, with one side stuck all the way in and the other all the way out (on each cylinder). This caused the drums to drag like crazy, and not stop engage at all. I replaced both cylinders with new units, replaced the shoes, and left the drums alone (still looked new). I figured I'd replace the shoes since the old shoes were glazed from all the dragging.

I also noticed one of the front axle nuts wasn't tight and was causing the wheel bearing to feel loose, so I tightened that up and all seems well. Also bolted up the Lemans wheels with the 225 50 15" Kumho Victoracers. I heard the 6.5" wheels and 225's won't fit an L body, but these have at least .5" of clearance before hitting the spring.

[jckrieger]

I forgot to mention... After the brake repair and bleeding all the lines, the car stops great. I haven't locked up the tires yet, but I do have the auto-x tires on the car so grip is amazing. Any idea how I should have these Konis adjusted for a tight auto-x track? I'm thinking about keeping the rears on full stiff and have the fronts set pretty soft.

[2.216VTurbo]

PM 'johnny' from Polybushings.com. He had his 86 GLHS very competative in autocross for many years and no doubt has some great set up tips:thumb:

[omnigoestohell]

Today I took the rear brakes apart (fronts have new calipers, rotors, and pads). I found both rear cylinders were stuck, with one side stuck all the way in and the other all the way out (on each cylinder). This caused the drums to drag like crazy, and not stop engage at all. I replaced both cylinders with new units, replaced the shoes, and left the drums alone (still looked new). I figured I'd replace the shoes since the old shoes were glazed from all the dragging.

I also noticed one of the front axle nuts wasn't tight and was causing the wheel bearing to feel loose, so I tightened that up and all seems well. Also bolted up the Lemans wheels with the 225 50 15" Kumho Victoracers. I heard the 6.5" wheels and 225's won't fit an L body, but these have at least .5" of clearance before hitting the spring.

coming from somebody who has the discs in the rear for the last 5+ years the front Minivan calipers/pads are really the hottest item in making your GLH stop great with minimal work. adding the rear discs didn't help much in terms of stopping for me and added some complexity as i had to swap the master and the prop valve at the same time --- i'd recommend not to bother with the rear disc and that having new rear drums will give you as much rear stopping power as you need. I also actually used stock chrysler minivan pads with great results. i heated them up a lot to break them in, after that I have had them in the car for YEARS including multiple road racing days and they just don't wear down very fast at all. other guys love some racing pads so your mileage may vary but don't hesitate to try the mopar stuff and let me know if your longevity experience is the same as mine.

I also haven't had any problem running 225/50's on 6.5" wheels on my omni, except of course hitting the transmission on full lock turns. i did have a problem running 225/50s on the rear on 6" wheels, the sidewall bulged too far out and rubbed on the rear spring but the front was never a problem.