7" vs. 9" vacuum booster for brakes...which is better?
 

67-c10...we are adding power brakes. Apparently the conversion can be either 7" or 9". Do any of you have experience with which is best? 7" presumably leaves more engine access room, but we have a straight 6 292. Does 9" give much more "boost"? Thanks in advance!

Mark

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

A 9inch booster is better. Its simple physics, the 9 inch has more sq in for the vacuum to act upon the the 7 inch. This helps apply more force with less pedal pressure. You have the room you can go to a bigger booster if their available.

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

Actually the unit that came on it was 11" in dia.
You have more boost. Sometimes they use a dual diaphragm booster in the smaller sizes to gain more room. If you have any questions feel free to call or drop buy we have done a lot of conversions.

Mike

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

Either run a factory 11" or dual 9". Don't bother with single diaphragm boosters less than 11".

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

OK...we are back on the brake project after many diversions. Any opinions out there as to the best all around solution to adding power brakes (w/ new master cylinder in the process) to what was a manual brake 67 C10?

Thanks.

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

Ummm, just do it.

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

Go to Webster and talk to mbgmike. He'll set you up or give you good advice on what you need.

Otherwise if you have a salvage yard that has some 67-72 trucks find one with the power brakes and take everything off that pertains to the p.brakes: mounting bracket, master cylinder, prop valve and include the brake pushrod inside the cab. The rubber hose and check valve you can get at local parts stores and if the booster is defective you'll have the core.

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

what i would do is to take a power booster off a 3/4 ton and put it on a half ton because the 3/4 ton booster is desgined to stop a heavier truck and the half ton is lighter and then u can have alot of brakes lol that is what i would do just go to autozone and order u a 3/4 power booster and use ur 1/2 ton booster as a core

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

Or to throw another twist,,,,convert to hydroboost and skip the vac booster

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

Either way get a booster bracket from CaptainFab... it allows you to use the late model 1988-1998 full size truck/Tahoe/Burb booster (smaller, less expensive, can be found at any parts store) unless your going for stock resto... The only thing to check is column shift clearance. Click HERE

You can also use this for hydroboost if you want to upgrade (now or later)...

http://67-72chevytrucks.com/vboard/a...1&d=1244429492

http://67-72chevytrucks.com/vboard/a...1&d=1244429543

http://67-72chevytrucks.com/vboard/a...1&d=1244429766

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

i like how that bracket is smaller and does not stick out as much as the stock one

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

X2, I love my hydroboost!

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

I like to see how the hydroboost looks and works on your truck. Could you post or send me some pics

Re: 7" vs. 9" vacuum booster for brakes...which is better?
 

PM replied, Pics and some info are on pages 9, 10 and 13 of my build thread. Link in sig