Vacuum boost brake conversion

[72kat]

I have a 72 c10 with a 350. It has disk brakes on front and drums on rear.
I want to convert to vacuum boosted brakes for better stopping.

I have been looking on Summit Racing and Jegs for the combo. master cylinder, vacuum, proportioning valve, etc. I see that there are different diameter vacuum boosters. 11 inch and 9 inch.

Thought I read that some guys ran into a conflict where the booster was too big and causing problems. So with a 350, what size should I get?

Thanks.

[72SB]

11" will work with an SBC but with some headers some go with 9" for better clearance. If you have a camed motor that makes low vacuum go with 11" or a dual chamber 9"

With that said I have a single 9" on my 67 SBC Camaro running a camed motor making 12" of vac, no problem

I have a Right Stuff conversion

[Caddylackn]

Taller aftermarket valve covers and Big Blocks (taller deck) can have issues with the 11" booster. The 11" should still fit but it may not be possible to pull the valve cover off without removing the booster.

If you have a BBC or tall valve covers, you should be able to unbolt the booster with the master cylinder and move it aside without unhooking the brake lines if you are careful.