What is minimum vacuum needed at idle to run vacuum booster brake set up

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sqhead

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I’m looking at a 383 stroker that has 14.5” of vacuum at idle. I’d like to stay with the vacuum booster but thinking I may need to get a hydro boost. What brake system are you running with 383 stroker or similar with that range of vacuum? Or has anyone tried the vacuum assist pumps?
 

sqhead

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squaredeal91

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It's a manual brake system converted to power. Original master cylinder still. And no vac reservoir but not much stop and go time on it.
 

Itali83

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My 350 with a cam has 15 at idle in neutral and 12 in gear. No problems with vacuum and assist braking. Been running this truck 15 years that way. No reservoir just stock set up. You’ll be fine.

Ben
 

Rustisbest

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Mine is around 11 in gear with a reservoir. No issues.
 

Ricko1966

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My camaro had a reservoir. 14lbs you won't even need a reservoir.
 

Don-T

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My K10 has a 383 that pulls 14” of vacuum at idle. It has vacuum power brakes and they work fiine.
 

TotalyHucked

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I've got a pretty rowdy cam in mine, never tested vacuum but I know it's toward the bottom of the scale at Idle. The power brakes work just fine.
 

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