Brake Booster Vac Hose Size

[Doppleganger]

Does anyone know the size of the vacuum hose for the brake booster? Gates claims its 11/32" but I know that check valve is much bigger than that.

I'm getting a vac fitting from the intake to the booster and need to know what size the barb has to be.

THX

 

[Toad455]

I'll measure one when I get home this afternoon, maybe somebody else will answer before then. I thought they were 3/8 just by memory, which isn't saying much.

 

[brooksman9]

Always used a 3/8” line myself too

 

[Doppleganger]

I almost thought they were closer to 1/2". ?!

IF I have my old one, I have no idea where it is.

 

[PrairieDrifter]

It is indeed 3/8.

 

[Doppleganger]

So maybe that 11/32 (.343) claim wasn't too far off?

Thanks fellas - I owe you all yet another beer.

 

[CalSgt]

This is the one I got for my ‘80, I measured out the fitting on my booster right at 1/2”.

My factory original fit okay with the 350 Vortec but the extra length of this one let me route it a lot more cleanly.

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[brooksman9]

Amazing how high vacuum hose has gotten these days. Bought 3’ at Autozone the other day. Cost $10.

 

[AuroraGirl]

Amazing how high vacuum hose has gotten these days. Bought 3’ at Autozone the other day. Cost $10.

brake booster hose is a separate distinct hose type compared to vacuum hose for other stuff.

 

[Bloodhound1981]

brake booster hose is a separate distinct hose type compared to vacuum hose for other stuff.

Don't tell my brakes that, they don't seem to know.

 

[dngrby]

My '85 uses 11/32 from the vacuum port on the carb to brake booster check v/v. My understanding is that while 3/8 fits, 11/32 ends up having a tighter fit. Also brake booster vacuum line is a heavier wall thickness. I have 3/8 line on my PCV to catch can and I'll be replacing that with 11/32 brake booster line soon here. NAPA sells it by the foot.