The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 04-17-2024, 09:55 PM   #1
72kat
Registered User
 
Join Date: Sep 2020
Location: Osborne
Posts: 16
Power brakes

I have a 72 c10 with 350 and 350 turbo. Was fixing it up with a buddy who was the brains of the operation. He unexpectedly passed away a month ago.
I seriously thought about selling the truck off as its a huge reminder. But recently, I thought damnit I'm going to finish it for him.

We put a edelbrock aluminum intake on it and a Holy 670 cfm street avenger carb. The truck has regular brakes (disks in front, drums in rear). We were going to upgrade the brakes to power brakes, but I'm not sure where to connect the vacuum line from the canister. Somewhere on the carb? Somewhere on the manifold?

Any help appreciated.
Thanks.
72kat is offline   Reply With Quote
Old 04-17-2024, 11:30 PM   #2
Rust_never_sleeps
Senior Member
 
Rust_never_sleeps's Avatar
 
Join Date: Jun 2022
Location: San Ramon,CA
Posts: 591
Re: Power brakes

It's the hex shaped fitting on the back of the manifold. I got one with 3 ports from Corvette Central, p/n 303313
Attached Images
 
__________________
1970 C10 Custom longbed 350/350
Rust_never_sleeps is offline   Reply With Quote
Old 04-18-2024, 12:10 AM   #3
RustyPile
Registered User
 
RustyPile's Avatar
 
Join Date: Dec 2017
Location: Elkhart, Texas
Posts: 1,841
Re: Power brakes

The booster vacuum hose needs to be connected to a large vacuum port on the intake manifold. That carburetor may have a large vacuum port at the rear of the throttle body. Connect the PCV hose there. Your aftermarket intake manifold may or may not have enough vacuum ports for everything. Some may need to be added. If it has a tapped hole between the carburetor flange/gasket area and distributor, install the factory fitting there and connect the transmission modulator vacuum hose and brake booster hose to it.
RustyPile is offline   Reply With Quote
Old 04-18-2024, 09:03 AM   #4
HO455
Post Whore
 
HO455's Avatar
 
Join Date: Feb 2016
Location: Portland Oregon
Posts: 11,350
Re: Power brakes

Good work on finishing the project! It will serve as a reminder of your friendship and the times you shared.
__________________
Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help.
RIP Bob Parks.
1967 Burban (the WMB),1988 S10 Blazer (the Stink10 II),1969 GTO (the Goat), 1970 Javelin, 1952 F2 Ford OHC six 4X4, 29 Model A, 72 Firebird (the DBP Bird). 85 Alfa Romeo
If it breaks I didn't want it in the first place
The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377
HO455 is offline   Reply With Quote
Old 04-18-2024, 10:07 AM   #5
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,731
Re: Power brakes

There’s a diagram in here for what ports to use.


https://documents.holley.com/199r10219-3.pdf
geezer#99 is offline   Reply With Quote
Old 04-19-2024, 05:48 PM   #6
72SB
Registered User
 
Join Date: Apr 2022
Location: Moorpark, CA
Posts: 774
Re: Power brakes

The Edelbrock intake should have a NPT plug near cyl 8 runner. Get a NPT elbow to 3/8 barb to connect to brake booster hose.
72SB is offline   Reply With Quote
Old 04-22-2024, 02:12 AM   #7
'68OrangeSunshine
Senior Member
 
'68OrangeSunshine's Avatar
 
Join Date: Feb 2002
Location: Tucson, AZ USA
Posts: 7,504
Re: Power brakes

I am sorry for your loss.
20 Years ago, I had to switch from a Holley carb to an Edelbrock because my Holley Guy was going thru an excruciating divorce. I needed a carburetor I could work on myself.
Also my regular mechanic/buddy came down with the Long Covid, and just doesn't want to work on trucks.
I must become more self reliant.
__________________


Every 25 years I like to rebuild that 292, whether it needs it or not.
'68OrangeSunshine is offline   Reply With Quote
Old 04-22-2024, 06:34 PM   #8
MikeB
Senior Member
 
MikeB's Avatar
 
Join Date: Jul 2000
Location: North Texas
Posts: 3,597
Re: Power brakes

Quote:
Originally Posted by '68OrangeSunshine View Post
I am sorry for your loss.
20 Years ago, I had to switch from a Holley carb to an Edelbrock because my Holley Guy was going thru an excruciating divorce. I needed a carburetor I could work on myself.
If you can work on an Edelbrock, you should be able to work on a Holley. There are lots of Holley how-to books out there. Buy one and don't be intimidated!

You'll find they have a lot of adjustability, even the least expensive street models.
__________________
Mike
1969 C10 LWB -- owned for 35 years. 350/TH350, 3.08 posi, 1st Gen Vintage Air, recent AAW wiring harness, 5-lug conversion, 1985 spindles and brakes.
1982 C10 SWB -- sold
1981 C10 Silverado LWB -- sold, but wish I still had it!
1969 C10 (not the current one) that I bought in the early 1980s. Paid $1200; sold for $1500 a few years later. Just a hint at the appreciation that was coming.
Retired as a factory automation products salesman.
Worked part-time over the years for an engine builder and a classic car repair shop.
Member here for 24 years! This is the very first car/truck Internet forum I joined. I still used a dial-up modem back then!
MikeB is offline   Reply With Quote
Old 04-23-2024, 02:28 AM   #9
'68OrangeSunshine
Senior Member
 
'68OrangeSunshine's Avatar
 
Join Date: Feb 2002
Location: Tucson, AZ USA
Posts: 7,504
Re: Power brakes

Quote:
Originally Posted by MikeB View Post
If you can work on an Edelbrock, you should be able to work on a Holley. There are lots of Holley how-to books out there. Buy one and don't be intimidated!

You'll find they have a lot of adjustability, even the least expensive street models.
Really my Edselbrock is a Carter AFB. But I decided I disliked Holleys every time I had a back fire and had to replace the Power Valve. Then the carb had to be set up again.
The AFB design doesn't have that flaw. After 250,000 miles on my last 292 with a 4160, R8007 390 CFM 4V Holley I was OK with it. But I always needed an Expert. When we got my present 292 build on the road in 2005, the 4160 was fine for the 500 mile break in. Then, on the way to work, it backfired for no reason. We couldn't get it to set up anymore. Warped base plate was the assumption. I looked into a separate base plate, but the price of a 500 CFM EDL-1404 [AFB Clone] was about the same, so I dumped the Holley.
Some people love them. I'm not one.
__________________


Every 25 years I like to rebuild that 292, whether it needs it or not.
'68OrangeSunshine is offline   Reply With Quote
Old 04-23-2024, 01:05 PM   #10
MikeB
Senior Member
 
MikeB's Avatar
 
Join Date: Jul 2000
Location: North Texas
Posts: 3,597
Re: Power brakes

Quote:
Originally Posted by '68OrangeSunshine View Post
But I decided I disliked Holleys every time I had a back fire and had to replace the Power Valve.
I had to replace the power valve in my first Holley back in the 1990s. No backfire that I recall, but it all of a sudden would bog when trying to go up even a slight hill. No idea what caused the blow-out.

For years now the carbs have had some kind of check valve that prevent blow-outs. I've never even looked into how it works, but never had another blow-out.

The only old vehicle I have now is my 69 C10, and it has a very old Edelbrock #1406. It works just fine, but I'm thinking about an AVS2 just because.
__________________
Mike
1969 C10 LWB -- owned for 35 years. 350/TH350, 3.08 posi, 1st Gen Vintage Air, recent AAW wiring harness, 5-lug conversion, 1985 spindles and brakes.
1982 C10 SWB -- sold
1981 C10 Silverado LWB -- sold, but wish I still had it!
1969 C10 (not the current one) that I bought in the early 1980s. Paid $1200; sold for $1500 a few years later. Just a hint at the appreciation that was coming.
Retired as a factory automation products salesman.
Worked part-time over the years for an engine builder and a classic car repair shop.
Member here for 24 years! This is the very first car/truck Internet forum I joined. I still used a dial-up modem back then!
MikeB is offline   Reply With Quote
Old 04-24-2024, 01:02 AM   #11
'68OrangeSunshine
Senior Member
 
'68OrangeSunshine's Avatar
 
Join Date: Feb 2002
Location: Tucson, AZ USA
Posts: 7,504
Re: Power brakes

Quote:
Originally Posted by MikeB View Post
I had to replace the power valve in my first Holley back in the 1990s. No backfire that I recall, but it all of a sudden would bog when trying to go up even a slight hill. No idea what caused the blow-out.

For years now the carbs have had some kind of check valve that prevent blow-outs. I've never even looked into how it works, but never had another blow-out.

The only old vehicle I have now is my 69 C10, and it has a very old Edelbrock #1406. It works just fine, but I'm thinking about an AVS2 just because.
I used to hafta keep a spare 8.5''Hg Power Valve in my glovebox. I guess they fixed that issue, but it was too late for me.

Sorry about the rabbit hole. I think I was trying to suggest Self Reliance to the OP.

The 1405 is what I think of as an equivalent to my Federal Mogul Carter AFB 9635S. I use the Edelbrock manual. Same as a 1406 but with manual choke. That's on a 350 in my '71 GMC Jimmy. [~600 CFM]
The 292 in the '68 Stepside has a 1404, manual choke but 500 CFM.
__________________


Every 25 years I like to rebuild that 292, whether it needs it or not.
'68OrangeSunshine is offline   Reply With Quote
Reply

Bookmarks

Tags
power brakes


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 07:47 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com