Disc Brake Size [Archive] - Chevelle Tech

: Disc Brake Size

Mar 8th, 09, 10:44 PM
I am buying a disc brake conversion kit for my 71 chevelle and i don't know whether to buy a 11 inch or a 9 inch. How can i figure out which one is right for my car?

Mar 8th, 09, 10:47 PM
11 inch. 9 is tooooo small. Actually I believe 11 is too small. I run 13".


Mar 8th, 09, 11:44 PM
Is their any way that i can somehow measure to just make sure that i but the right kit?

Thanks, Chris

Mar 8th, 09, 11:48 PM
The real question is what wheels do you want to run as goes the bigger the brakes the bigger the wheels need to be.

Mar 9th, 09, 12:17 AM
What do i measure to make sure i get the right size?

Mar 9th, 09, 12:28 AM
go to one of the sponsors web sites and see what there stock kits are. They should tell you what size wheels will fit with there kits.

Mar 9th, 09, 12:36 AM
Wait, do you mean the size of the rotors or the booster? As far as I know, all of the "stock-type" front disc kits use 11" rotors (OK, I lied -- some use 10.5" rotors and metric calipers).

BUT, most list multiple different power brake boosters. If we're talking power boosters, 11" is the "stock" size and works well, but might not clear tall valve covers on some applications (big block?). Smaller 9" boosters clear tall valve covers, but don't provide as much assist.

So let's back everything up a bit...

-- What size wheels are you running (15", 14", ???)
-- What are you looking for in a disc conversion (better brakes? better LOOKING brakes?, "bling", ...)
-- What engine do you have (big block? small block? I6?)