REAL Stopping power on a 1970 Chevy

[bikertim]

Ok -- what is the best way to get better performance out of my brakes? I have converted to disc on the front -- rebuilt the rear drums -- but performance still isn't what I want it to be. I have power brakes -- and an adjustable proportiioning valve that made it so i could adjust the front to rear bias. Works ok but....

Are larger rotors the way to go? More piston calipers? Disc on the rear? More modern power booster and master cylinder?

I don't want to break the bank here, but I don't want to destroy my truck because the stopping power is weak. I live in the Phoenix AZ area, land of the haul a.. and slam on your brake crowd, and 70s technology isn't up to speed on the stopping front.

Many of you have spent tons of money on this.... what shoudl I do?!?

[LMDGUY]

what disk brakes did you use? if they are a factory type (single piston) caliper they are big inprovement over drums. But maybe look into doin a dual piston caliper upgrade?

[N2TRUX]

First and foremost, is your current set up working correctly? If you feel that you have got the most out of your system, lets move up from there.

The quickest and cheapest step up is quality pads and shoes. There are several companies out there that sell cryogenic treated pads, shoes, rotors, etc. One of the best known is Praise Dyno Brakes I'll let you spend some time looking there, but you can maximize your current system with several options there.

Next up the price scale are bigger and better calipers. There are several options available to replace the stock caliper and utilize your current rotor. Any time you had more clamping force via piston volume you will experience shorter stopping distance. Take a look at the deals being offered by CPP right now.

Here is one- D52 Wilwood caliper Couple these with a slotted rotor, and your pretty much maxed out for a 12" disc set up.

If you want to stay with 12" easy to replace rotors, and would like to improve the rear, consider a rear disc conversion. This will ensure you have maximum stopping power, and minimize brake fade potential.Rear disc kit


Those are all what most would consider as affordable options. Moving to the more expensive upgrades, you can look at 13" or bigger rotors, multi piston calipers, etc. There is no doubt the big systems will make HUGE improvements over the best 12" system. The question is how much do you want to spend.

Like the old saying of "Speed costs, how fast can you afford to go?". The same theory applies to how quickly you would like to stop...

[bikertim]

Thanks for the information -- gives a couple of good options. SOunds like I need to probably give CPP a call, break out that wallet and get'er done! Thanks again.

[suville]

Have you looked into a hydro boost set up you still have all stock components so repairs and replacement is as near as NAPA or ? Just a thot Check out Captain Fab hes a vendor here, in Idaho too Ha!

[andrewmp6]

If your running a 17 or bigger rim you can get some big brakes for it.

[CSGAS]

Before worrying about additional upgrades, check the least expensive problems first.

When you upgraded to front discs, did you check the lines or change any out? 40 year old brake lines tend to have rust--meaning moisture int he lines.

Since your performance did not improve as much as you expected I really would suspect some problem with parts that are common to both systems, which leads me to those lines.

The cheap way to check, is just flush ALL the brake fluid out of the system and refill with fresh fluid. You may even benefit in AZ from using hi-temp (not silicone, just hi-temp) brake fluid. If that improves your system drastically but then fades over time, then plan on replacing your lines.

[project67-stepside]

did u replace the master cylinder< sounds like u didnt and the pressure for drums is about 1/2 the pressure for disk? It could also be the prop valve if its a drum/drum same problem>

[bikertim]

Yea I changed the MC and brake booster at the same time -- tried factory proportioning valve and didn't seem to work right. Went to the adjustable and worked great -- I was able to dial it in.

There was a big improvement when I went to discs, but I want more braking performance. When 99% of the cars around you are newer cars with 4 wheel disc anitlock brakes -- and they slam on their brakes your in trouble. I used to try and just leave plenty of distance, but now for some reason people think if there is room in front of you they can fill it!

Thanks for all the advice!

Tim

[Painter D]

My brakes suck too. I have the same setup as you do I think it's just old technology ,like you said.

[doug70]

You could always go to hydroboost. I am doing that on my k20 as part of the project. The PS pump internals are basically the same as what you have. I am doing it because the donor truck had it and the 427 going into my truck doesn't produce a lot of vacuum. Kind of expensive, but an option.

Doug