I currently have front disc and rear drums with power brakes. My brake booster is the original 11" and I need to change it to a smaller one 9" or 7" for clearance. My question is, is there a difference in the master cylinder with different booster sizes or can I keep my master cylinder and just replace the booster ( I just bought a new master cylinder beginning of the year)? Also does anyone know were I can find just the booster, so far all I have found are the master cylinder and booster as a kit?

Thanks
Josh

Check here with Steve, he may have one for you. http://www.brakeboosters.com/index.htm

I put the 7" dual diaphram master power booster in my car the master cylinder fit but I believe (it was years ago) that it comes with a new rod or the rod has to be adjusted. Master power or SSBC tech will tell you for sure