I've got regular power brake on my car and nothing has been changed on it at all. So with a 1980 GMC Caballero, my next step under the hood is a chrome master cylinder and power booster set combo. How do you tell what size, etc to get 7", 9" or 11" booster and I assume its a dual diaphram. Where would be the place to check out buying one. thanking you in advance, Michael

A street rod universal master and booster will require some modification and i assume thats what your looking at by posting those different sized boosters ? I would look to the lowrider crowd for what you are after if its not painted in there cars its plated . I would look for a direct fit combination unlesss your ready to do some modifications . There are places that rebuild power boosters you could always have it plated during the rebuild same with the master cylinder.
Tim

I guess by just one answer I confused you or I confused myself. I just want to get a combo Booster W/Master Cyl. and do not know where else to look. I've got the Tuff Stuff Performance catalog and it all certainaly looks like one of the best. ???:smileyb:

I believe steelybill asked this question a while back and there were a few good replies about vendors, but as for the 7",9" and 11" the only true difference is the size for clearance and they come in both single and dual diaphram. The only time I have seen dual diaphram is for 4 wheel disc brakes.

You will have to get a booster with the correct bracket on it to mount it to the firewall, or, there are separate brackets available also. Check some of the sites, like Summit, UPGI, etc and see what's available in chrome plated assemblies.

Here's a general overview of how brake boosters work:
http://www.classicperform.com/tech_articles/PDF/Dems_DA_Brakes_3.pdf


This should help you decide what size booster and master to use:
http://www.classicperform.com/PDFs/BoosterBrakePressureChart.pdf
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