Hydroboost

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Gussie

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Hello everyone. I am interested in changing to hydroboost in my 86 k20 which currently is vacuum booster. I was thinking about using a hydrobooster from a 86 k30. Is it as simple as that besides new plumbing and perhaps corresponding pushrod? I see after market kits fir $800 but thought I could piece together cheaper. Thanks
 

Mr Clean

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If you can find a complete set up it is IMO one of the best things you can do to a Squarebody. What I mean by complete set up is... The Hydroboost, master cylinder, push rod and brake pedel.
 

Mr Clean

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I paid 55.00 for my last set up. Took me about 40 minutes to pull it from the truck in the salvage yard. If you find one from a SB it is almost a direct replacement.
 

Strick

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I used the hydroboost from a CUCV when I built my '55 Chevy truck. I love it; the brakes work regardless of how the engine is or is not running. The accumulator on the unit will allow a few stops even after the engine has stopped running. As long as you have all the pieces, the swap is straight-forward. Welcome to the site as well.

HS
 

Gussie

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Thanks everyone. So the k20 brake pedal is different than a k30 w/ hydroboost? Also, can the stock proportioning valve on my k20 be used which is mounted on the lower front crossmember or does the k30 p. valve which appears to be collated to the M.C. need to be used instead?

I really am having fun on my first big resto...I keep finding little mods here and there to make which makes it more cool. Just getting rear springs on was fulfilling lol
 

Mr Clean

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454 BBC, & 383 Stroker
The Proportioning valve will be fine if you are staying with drum brakes on the rear. I changed mine out only because I swapped to disc brakes in the rear. The rod on hydroboost has a larger hole on the side that hooks to the pedal. You can use your pedal but you'll have a little play in it.
 

fast 99

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Try to find one that isn't leaking fluid. They are relatively expensive to replace and are prone to leaks with age.
 

ross632

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Is the pin for HB and vac in the same location? If not what is the difference between them. Just ordered HB and MC from rock auto but thinking I can make a bushing to take up the slack in pin.
 

Mr Clean

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454 BBC, & 383 Stroker
Is the pin for HB and vac in the same location? If not what is the difference between them. Just ordered HB and MC from rock auto but thinking I can make a bushing to take up the slack in pin.
Yes the pin is in the same location.
 

Snoots

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SquareRoot

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^^^^Yup. I was gonna say that but I'm glad you beat me too it! Snoots for the kill.
 

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