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Where to hook up brake booster vac line ?

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Old 07-09-2007, 08:30 AM
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Where to hook up brake booster vac line ?

I am about to get my car on the road and I am having trouble figureing out where to put the vac line for the brake booster. I have the pcv valve hooked up to the back of the carb. So I have a spot in the intake where I can screw a fitting in. But when i go to the parts store they have nothing. What can I use ??
Old 07-09-2007, 09:05 AM
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Re: Where to hook up brake booster vac line ?

Hard to believe a parts store doesn't have that.... even VatoZone, which barely qualifies as a parts store (about the way a home-improvement store qualifies as a hardware store or lumber yard), has stuff you can use to make that.

All you need is a 3/8" hose barb with ¼" pipe threads; and a ¼" pipe elbow.

If you can't get those things at your parts store, any place with plumbing supplies - even a Home Depot - will have them.
Old 07-09-2007, 09:54 AM
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Re: Where to hook up brake booster vac line ?

The hole on the back of the intake looks bigger than 1/4
Old 07-09-2007, 10:10 AM
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Re: Where to hook up brake booster vac line ?

It is. Because it's not ¼".

It's ¼" PIPE. Which is closer to about 5/8" diameter or so.
Old 07-09-2007, 10:33 AM
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Re: Where to hook up brake booster vac line ?

Was this on a stock Intake? You might end up going to a junk yard and pulling on off almost any 305 / 350 / 400 car or truck. They are almost all the same. I found the same problem here when I tried to get one for my intake. Napa found one at the last minute. I am not 100% sure but it might be 5/8 pipe like the previous posts said.
Old 07-09-2007, 11:25 AM
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Re: Where to hook up brake booster vac line ?

thanx!!
Old 07-09-2007, 12:16 PM
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Re: Where to hook up brake booster vac line ?

No; it's ¼" PIPE, which is about ½"-5/8" DIAMETER.

2 very different things here.

Go to the hardware store, look in the brass fitting in the plumbing dept, for a ¼" pipe elbow and a ¼" pipe to 3/8" hose barb. That's EXACTLY what you need. Then stick the 3/8" hose to the booster on it.
Old 08-29-2007, 08:15 AM
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Re: Where to hook up brake booster vac line ?

Does anyone make a low profile fitting for holley carbs.

I have a holley 750 on a Edelbrock RPM airgap. I am limited on under hood space. I might be able to get a 1/2 space under the carb, but thats about it.

Any ideas besided cowl hood or drill/tap the intake runner?
Old 08-29-2007, 11:13 AM
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Re: Where to hook up brake booster vac line ?

Not that I know of.

Drill & tap into the side of the plenum. Much neater.
Old 08-29-2007, 12:23 PM
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Re: Where to hook up brake booster vac line ?

I had the same issue using the Holley and BG carb with the float bowls in junction woth the Edel intake. If you look at Holley intakes, the port is moved over on the rear runner. Edel, in the skeem to try to get you to buy their carbs (which they stole design from Carter) decided to tuck it in the worst possible spot. O used the rear carb port (large one) for the brake booster hose. After I finally decided to get my PCV working, I used the stock low-profile eblow from my old intake. These are availible through Classic Ind I think still, any orig. Q-Jet F-body and Motormite (HELP) parts section at some stores. The hose outlet is small, which is why I chose to use the carb port to supply the booster. The Edel intake threaded hols is beveled, so you will need to tap it deeper straight. I pulled the carb, used a wet rag inside the intake to catch the shavings and another to cover the carb opening, tapped it deeper/straight, than screwed the port in as far as it would go and used black RTV as a extra precautionary sealer, then I got a 'thick' Holley carb gasket to add some more clearance. No problems, they both work well and the rear pump works without a hitch. I used some silicone hose I had, an adapter and a regular LG4 right angle/single port PCV valve.
Originally Posted by bluegrassz
Does anyone make a low profile fitting for holley carbs.

I have a holley 750 on a Edelbrock RPM airgap. I am limited on under hood space. I might be able to get a 1/2 space under the carb, but thats about it.

Any ideas besided cowl hood or drill/tap the intake runner?
Old 08-29-2007, 12:29 PM
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Re: Where to hook up brake booster vac line ?

The part is still availible from Classic Industries. #G5179 It list it for the 67-70 C/F but its what it looks like I had on the LG4 intake exactly. Says 3/8-18 Pipe Thread and 3/8 nipple. Another on here said it was a 1/8 pipe. So Im not sire about that. If you could go to a u-pull-it yard and take your plug that in there now, or refer to the Edel intake instructions on the port thread size. Hope this will help out or at least give you an idea/direction.
Old 08-30-2007, 07:27 AM
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Re: Where to hook up brake booster vac line ?

Thanks guys for the good info.

I really hate to drill/tap with the intake still on the car. I dont want to chance getting shavings in the motor. But I see drilling in the side of the plenum with the carb off, I could collect all the shavings.

I will see if I can find one of the low profile fittings and maybe go with a spacer. I kinda wanted to play around with some spacers to see if it picks up at the track.

thanks

Oh yeah, I didnt mean to hijack the thread. Although it did add good info to it.
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