This year's project - brakes

[Dleslie212]

Time for this years project - completely revamping the brakes on my 77 K10. I was hoping for some help in selecting a few kits. Budget is between 3 and 4k

I’m going to be swapping to a Hydroboost system and have this one picked out - thoughts?

1973-87 Chevy, GMC Truck Hydro Power Brake Boost Kit with Wilwood Master Cylinder


I also want to spring for a rear disc conversion, and possibly replacing calipers up front as well to something a bit more beefy. The end goal here is for the truck to stop on a dime, and feel as close to a modern car as possible. I had my wife drive it in to her workplace a few months back and she’s since swore to never drive it again as it just doesn’t brake all that well. I’m hoping to find an all around kit - I’d love for the front and rear calipers to all match. Does anyone know of a complete kit that comes with the rear conversion and replacements for the fronts?

I did find this, but I’m curious if anyone knows of anything better. The single piston is concerning - aren’t there typically two pistons?

https://www.summitracing.com/parts/t.../1977#overview

[Shugalou]

When I was thinking about converting to rear disk set up, the shop swayed me away from it telling me the factory set up is pretty good and was designed to stop carrying a full load...I haven't driven a disk converted truck to see if there is any difference and if that opinion holds any weight.

To save yourself some money you could try upgrading the lines to stainless drop lines. and put a more aggressive pad EBC yellow stuff with some slotted rotors. That's what I have done (actually stop tech rotors and pads but I wished I went EBC) and it stops pretty good and my tires are in desperate need of replacement (20 years old probably)

[kipps]

Originally Posted by Shugalou

When I was thinking about converting to rear disk set up, the shop swayed me away from it telling me the factory set up is pretty good and was designed to stop carrying a full load...I haven't driven a disk converted truck to see if there is any difference and if that opinion holds any weight.

Drums have more stopping force, but they are a little more likely to grab. Disks can be controlled more precisely.

The reason for this, is drum brakes are partially 'self-actuating', and don't need as much line pressure to operate. Disks are not self actuating at all, so they need higher pressure, and can be controlled more accurately.

If you go with a disk brake conversion in the rear, definitely pair that with an adjustable proportioning valve. That way, you can dial in the rear brakes, for maximum braking without locking them up on a hard stop.

[79vette]

Is there anything wrong with the existing brake system? I have a 77 K5 on 31s and an 86 K5 on 33s, and both will lock up the tires on dry pavement. 77 is a 350 with vacuum brakes and the 86 is a diesel with factory hydroboost.

What brake performance are you looking to add, specifically? As other posters have stated if you want better pedal feel discs and hydroboost could help with that. If you're racing or towing heavy and are getting brake fade you might need some upgraded parts, but both of those seem unlikely in a K10.

For what it's worth, I can't see needing fancy brakes on a half ton outside of those applications and I feel like the money could be better spent on engine, trans, suspension, steering, or interior upgrades and give much better bang for the buck. But it's your truck.

[Factory Guy]

Do what you want but Scotty Baccus feels Hydra boost is a waste of time.

I am in the middle of re-doing my brakes as I am like you want better stopping.

Just got my parts. I am getting ready to preform Scotty Baccus brake upgrade, which involves a better master cylinder and a new reservoir so It will all fit under the hood.

[Shugalou]

Great info and just when I thought I was done with the brakes. Never heard of the master upgrade - sucks because I bought a stock replacement when I redid the entire system.

[franken]

The rear brakes are about 25% of the braking action so converting to disks isn't going to make much of a difference.

[kipps]

Originally Posted by franken

The rear brakes are about 25% of the braking action so converting to disks isn't going to make much of a difference.

The advantage of disks is they can be controlled better. They're less likely to lock up suddenly if you're on them hard. This is the same reason that front brakes have universally gone to disks.

Drum brakes still have superior stopping power, but they 'grab' worse.

I recently had a scare in a 1981 f150. I wasn't paying attention like I should have been, and had to slam the brakes to avoid slow traffic in front of me. I was going sideways down a interstate on-ramp with nothing more than some hard braking. A properly proportioned disk brake setup would have been a little less likely to lock up like that.

[Dleslie212]

The brakes just have not been good - I'm almost positive my vacuum booster had gone out. I weigh 225, and I'd been having to stand on the pedal to get it to stop. I've previously gone through the brakes completely within the last two years - rotors, drums, everything has been replaced. I figured if I'm having to replace the vac booster, I may as well convert to hydro anyhow.


Moot point now - the hydro assembly has been installed. I'm just waiting on a set of new power steering hoses. The new hydro assembly came with a new adjustable proportioning valve, so I need to get my old hard brake lines plumbed into that.

I'm assuming my old proportioning valve needs to be uninstalled, correct? That way I'm using only the new adjustable? I've read that having two proportioning valves can cause weird problems