Brakes. What should i do? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

dmartin1 · 08-19-2014, 04:09 PM

im at the point of almost completely reassembling my 69's entire front end after stripping painting etc.

the truck is a power drum factory and still has it all there.i plan to swap to disc later down the road(shortly down the road)

im at the point of installing my brake hardlines and from what ive read the hard lines are much different from drum to disc?

my plan was to assemble with the power drums to get the truck on the road and in one piece then swap later, but it looks like the engine would have to be pulled again to replace the brake hard lines for disc?

anyway to install disc lines and adapt to power drum block and slaves? im kind of stumped on what to do.brains going 90mph

**lolife99** · 08-19-2014, 04:13 PM

No need to replace the hard lines at the crossmember.
You will have to bend new lines to work with a disc brake M/C and prop valve.
I would go ahead and install some 63-70 disc brake spindles and do it right from the beginning.
I hate opening up a brake system and trying to keep the brake fluid from eating up all the painted surfaces.
I used ECE's conversion brake hoses for the front calipers and bent new lines to the prop valve.

**lolife99** · 08-19-2014, 04:14 PM

Call ECE and talk to Stan or Mark.
www.earlyclassic.com

dmartin1 · 08-19-2014, 04:31 PM

whew! thanks for the clarification!

i will see if i can work budget to allow to start off with discs.

thanks keith you the man

**jocko** · 08-19-2014, 04:38 PM

I thought that the front disk lines were 3/16" from the distrib block to the calipers on stock GM disk setup(?) (and 1/4" lines from the block to the rear drums). Standard all-drum arrangements are 1/4" all the way around. I know it will work with 1/4" lines all the way around, but without a prop valve to compensate, won't there be a mismatch on the correct amount of pressure applied to the front disks if 1/4" lines are used up front?

Concur with Keith - I would try, if at all possible, to do it now and do it once, even if it incurs a little delay. Understand it's a budget issue, completely understand you want to get it going too.

**lolife99** · 08-19-2014, 07:13 PM

Yes you need a disc/drum prop valve or an aftermarket adjustable prop valve.
I see no reason to change the location of the stock steel lines unless you absolutely have to.

08-19-2014, 04:09 PM	#1
dmartin1 Registered User Join Date: Aug 2008 Location: mohave valley,arizona Posts: 1,088	Brakes. What should i do? im at the point of almost completely reassembling my 69's entire front end after stripping painting etc. the truck is a power drum factory and still has it all there.i plan to swap to disc later down the road(shortly down the road) im at the point of installing my brake hardlines and from what ive read the hard lines are much different from drum to disc? my plan was to assemble with the power drums to get the truck on the road and in one piece then swap later, but it looks like the engine would have to be pulled again to replace the brake hard lines for disc? anyway to install disc lines and adapt to power drum block and slaves? im kind of stumped on what to do.brains going 90mph __________________ 1969 Shortbed in progress 1982 short step, few suspension and motor upgrades.getting a 468 1978 Shortbed fleet side bonanza fully loaded 1978 k20 Silverado loaded.currently engine-less 1989 k10 suburban 9" lift 65 nova And more

08-19-2014, 04:13 PM	#2
lolife99 67-72 parts collector,… Join Date: Nov 2002 Location: Mid-MO Posts: 22,692	Re: Brakes. What should i do? No need to replace the hard lines at the crossmember. You will have to bend new lines to work with a disc brake M/C and prop valve. I would go ahead and install some 63-70 disc brake spindles and do it right from the beginning. I hate opening up a brake system and trying to keep the brake fluid from eating up all the painted surfaces. I used ECE's conversion brake hoses for the front calipers and bent new lines to the prop valve. __________________ Keith Convert to disc brakes. http://67-72chevytrucks.com/vboard/s...d.php?t=444823

08-19-2014, 04:14 PM	#3
lolife99 67-72 parts collector,… Join Date: Nov 2002 Location: Mid-MO Posts: 22,692	Re: Brakes. What should i do? Call ECE and talk to Stan or Mark. www.earlyclassic.com __________________ Keith Convert to disc brakes. http://67-72chevytrucks.com/vboard/s...d.php?t=444823

08-19-2014, 04:31 PM	#4
dmartin1 Registered User Join Date: Aug 2008 Location: mohave valley,arizona Posts: 1,088	Re: Brakes. What should i do? whew! thanks for the clarification! i will see if i can work budget to allow to start off with discs. thanks keith you the man __________________ 1969 Shortbed in progress 1982 short step, few suspension and motor upgrades.getting a 468 1978 Shortbed fleet side bonanza fully loaded 1978 k20 Silverado loaded.currently engine-less 1989 k10 suburban 9" lift 65 nova And more

08-19-2014, 04:38 PM	#5
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 17,960	Re: Brakes. What should i do? I thought that the front disk lines were 3/16" from the distrib block to the calipers on stock GM disk setup(?) (and 1/4" lines from the block to the rear drums). Standard all-drum arrangements are 1/4" all the way around. I know it will work with 1/4" lines all the way around, but without a prop valve to compensate, won't there be a mismatch on the correct amount of pressure applied to the front disks if 1/4" lines are used up front? Concur with Keith - I would try, if at all possible, to do it now and do it once, even if it incurs a little delay. Understand it's a budget issue, completely understand you want to get it going too.

08-19-2014, 07:13 PM	#6
lolife99 67-72 parts collector,… Join Date: Nov 2002 Location: Mid-MO Posts: 22,692	Re: Brakes. What should i do? Yes you need a disc/drum prop valve or an aftermarket adjustable prop valve. I see no reason to change the location of the stock steel lines unless you absolutely have to. __________________ Keith Convert to disc brakes. http://67-72chevytrucks.com/vboard/s...d.php?t=444823



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