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-   -   Improving brake performance (https://67-72chevytrucks.com/vboard/showthread.php?t=579023)

chevy72blu 05-06-2013 01:56 PM

Improving brake performance
 
I have a 72 C10 SWB (LWB conversion) with front disks on 73-87 spindles, booster, and rear drums. The truck has been converted to 5 lug.

I've noticed that one of my rear rubber hoses has a slight leak and the MC is going out. I figure now is a good time to go through the brakes and while doing so, make some improvements. With new components installed and properly adjusted, I would say the brakes do an adequate job for mundane street driving, but I have never been impressed with them.

The two options I am considering are converting to hydroboost (I have a junkyard pull out from an 86 disel burb that needs to be rebuilt) and/or converting to disks in the rear.

The disk swap seems relatively straight forward, but its pricey as well at $240+ for brackets and $400+ for the kit. I would then need a new prop valve and misc parts.

Is the hydroboost a better option? I realize that both would be ideal, but I am also rebuilding my entire front end and spending that much would definitely land me in trouble with the wife. Then again, definitely cheaper than price of rebuilding the truck and hospital bills (at best)?

ECE has a drum brake upgrade kit that is supposed to increase stopping power, but at $500 it seems like a better idea to just switch to disks.

I'm not trying to build a corner carving race truck, but I would like it to stop more on par with a modern vehicle. Any ideas?

Tinkermc 05-06-2013 02:01 PM

Re: Improving brake performance
 
my personal fav would be go for disc front and rear. Stop on a dime and get 9 cents change from anything short of 100 mph from stop light to stop light.

PanelDeland 05-06-2013 02:09 PM

Re: Improving brake performance
 
You should only have one rear hose.A leak in it will cause air in the system also.You probably would have better brakes with the rear disc since the Hydro boost will only lower pedal pressure.One big factor in brake efficiency is the pads.I would look at a premium pad and maybe turning the disc/drums you have along with the hose replacement before I started any mods.If you can lock up all 4 wheels during braking then the brakes aren't the limiting factor,traction is.My personal opinion is that a properly functioning disc/drum system is plenty for one of these trucks since I've always been able to lock all 4 with it.

chevy72blu 05-06-2013 07:29 PM

Re: Improving brake performance
 
Thank you for the replies.

Yes, I meant to say single rear hose. It was a typo.

I can lock the front wheels now (even with a leaky rear and a bad MC), but I have to stand on it with the force of God to do so. Although, I have never been able to lock the drums, it's my understanding that the front wheels do the vast majority of the braking anyway. Sounds like new performance tires and hydroboost down the road (to improve pedal feel) is the way to go.

Shyguy 05-06-2013 07:57 PM

Re: Improving brake performance
 
We put the front cradle with power disc brakes and the rear end with drum brakes off a '71 truck on my '67 swb stepper.

I can lock up all 4 brakes easily. Of course locking up the brakes is not a good way to maintain control so I don't do it often.

My son's work truck has power drum brakes and has no problem stopping the lwb truck with a 454.

The point I guess I am trying to make is if the brake system is operating the way it was designed on these old trucks they will stop just fine.

When many people do brakes they forget to have the discs or drums turned to remove the glaze.

Hydro-boost power brakes are used on heavier duty trucks, my '75 C-30 dually and my '92 K-3500 both have the hydro-boost brake system.

SS Tim 05-06-2013 08:41 PM

Re: Improving brake performance
 
Your truck was sitting what six years and it sounds like you just started driving it without inspection or service. This is not a good idea with a DD. I think you need to really get the brake system up to factory spec. before deciding if changes are needed. IMHO disc/drum is a non-problem for most people and more to the point "I want" vs "I need". Set up properly, with drums and rotors to spec. and premium pads, the factory installation will give the performance you need. Too many people shop brake parts by price and want "lifetime" pads thinking they get performance too.

Of course you will still need to address the existing problems with your system. You never addressed the apparent brake system mismatch in your last brake thread (my post #10).
http://67-72chevytrucks.com/vboard/s...d.php?t=578172

A lot of mismatched parts are never going to give you the factory designed performance and adding to a bad setup is not going to make it wonderful.
Identify, correct and then evaluate.
By your own admission you are technically weak on drum brake service. Buy a brake book and do some learning before deciding that throwing discs on the back is going to make everything just great.

Lee H 05-06-2013 10:14 PM

Re: Improving brake performance
 
With all the parts in good working order you should be able to lock up the fronts with ease and the backs will work as designed and slow that truck up rather quickly. Sounds like you have some work to do to get your system in good working order. I'd start with Tim's recommendations and get your current system figured out first.
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chevy72blu 05-07-2013 01:58 PM

Re: Improving brake performance
 
Thank you for the responses. I was able to get my wife's car back on the road (new fuel pump and filter, not fun on a "new" car), and my truck has not been driven since I discovered the leaking rear hose.

I was able to ID my MC, and it is correct (as is the rest of the brake system from my inspection, excluding HD rotors from a 73-87). I just ordered all new parts as well as drum rebuild kit from ECE, should be here in a few days.

Can anyone recommend me a good book or video series on rebuilding and adjusting drums? I am familiar with disks, but as noted I have little experience with drums (had plenty of poor jobs done at places like Just Brakes and I'd like to learn myself).

Lee H 05-07-2013 02:28 PM

Re: Improving brake performance
 
Shop manual has all the info you will need. You will need to have the rotors and drums turned in order to take best advantage of your new brake components. Do one side at a time so you have a reference point while things are apart.

chevy72blu 05-07-2013 02:39 PM

Re: Improving brake performance
 
Thanks, Lee. I have the factory service manual. Would the Overhaul manual be a good idea as well?

Lee H 05-07-2013 03:17 PM

Re: Improving brake performance
 
The factory service manual is enough for brakes. You can always come back to the forum with specific questions. Lots of nice folks willing to help out.

GRX 05-07-2013 04:18 PM

Re: Improving brake performance
 
Yep. With all the parts in good working order you should be able to lock up the front easily.
Heck, my '69 LWB stepper has front drums and still locks 'em up. ;)

cdowns 05-07-2013 04:49 PM

Re: Improving brake performance
 
factory service manual will show that your truck came from the factory with 5lug axels

guess you didnt get to that section yet

chevy72blu 05-07-2013 05:00 PM

Re: Improving brake performance
 
My truck came with 8 lug. Thanks for the help.


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