Brake Conversion - Which Brake Booster

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Aug 22, 2008 | 10:47 PM

DarkWolf40

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Brake Conversion - Which Brake Booster

Converting to front disc brakes, the 77 doner's brake booster is about 10 1/2 inches diamter and hits the valve cover. The original 67 booster is about 7 inches diamter. Who knows which year will fit? I need a booster less than 10 inches OD and with the 4" shaft like the 77 unit.

Aug 23, 2008 | 05:56 AM

jowilker

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From: Creedmoor, North Carolina

What engine is in the truck? For the year and V8 it should be a FE 352/360/390, and that booster on the proper mount will not hit it. Does your truck have custom extra high valve covers? There is about 1 1/4" space on my truck with Edelbrock valve covers.

It shouldn't hit if it is a larger 460 engine. I have seen a smaller diameter booster on a 74 F250 but don't know how many years it was used.

John

Aug 23, 2008 | 12:06 PM

Ford_Six

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From: The Big, Oregon

I am using 75 disk brakes, proportioning valve, and master cylinder in my 72, and with the 72 booster it stops great. Everything lined up and bolted up, the pin stickout was the same between the two boosters, etc. There's an article in process about this.

Aug 24, 2008 | 03:26 AM

Dirt racer

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From: Minnesota

You could just move the booster over to the drivers side. I moved mine about an inch on my 75 F100 4x4 and it was pretty easy. Just drilled new holes using the bracket as a template. The pedal I just cut the spacer on the shaft and put it on the other side. Then ground out the center hole to match. Now I can run my tall valve cover on the 429.

Aug 24, 2008 | 10:01 AM

nevrenufhp

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From: Sacramento

If you wanted to try, a hydroboost is smaller and gives about 5X the boosting as a vac booster.

Aug 24, 2008 | 07:26 PM

DarkWolf40

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Got the original 352 in it, its rebuilt as a 410 with Eldelbrock heads and cast aluminum valve covers so thats why there's no clearance.

So whats the diameter of the 72 booster? Maybe that would be the esiaest fix. Don't really want to move everything over an inch if I can keep from doing that.

And what is the world is a hydroboost? Where would a guy get one to bolt up to a bumpside brake system?

Aug 24, 2008 | 07:31 PM

nevrenufhp

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From: Sacramento

It's powered by the power steering pump. It originated in Med duty trucks. Even the new Mustangs use hydroboooost. Carcrafter22 on the CrownVic buildup put it in his 67 (cant remember which page though). Not too terribly hard to adapt in. When I go to power steering & disc on mine, I wont even look at getting a vac booster. I'll go from the worst brakes(4 wheel drum/ non power assist) to superior stopping, and feel comfortable towing a trailer.