'75 Vacuum port sizes
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Joined: Jan 2010
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From: Houston TX
'75 Vacuum port sizes
I'm seeing too many different answers on vacuum port sizes for my '75 with Eldelbrock Performer 600 carb and Edelbrock Torker II intake. Specifically, I'm looking for the correct sizes for:
1. Distributor advance off of carb (3/16"?)
2. Trans kickdown off of manifold (TH400)
3. Brake booster off of carb
The lines I have now are flimsy and compress on deceleration.
Thanks!
1. Distributor advance off of carb (3/16"?)
2. Trans kickdown off of manifold (TH400)
3. Brake booster off of carb
The lines I have now are flimsy and compress on deceleration.
Thanks!
Race Director
Joined: May 2006
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you are using the wrong material for the hoses, sounds like windshield washer hose. You should be using fuel line hose which typically would be 3/8, 5/16, 1/4.
1. Measure the size of the nipple on the vacuum unit.
2. Should be a metal pipe coming up from trani, measure diameter.
3. Measure size of valve that hose connects to on booster.
1. Measure the size of the nipple on the vacuum unit.
2. Should be a metal pipe coming up from trani, measure diameter.
3. Measure size of valve that hose connects to on booster.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
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From: Oxford MA-----You just lost the game!!!!
you are using the wrong material for the hoses, sounds like windshield washer hose. You should be using fuel line hose which typically would be 3/8, 5/16, 1/4.
1. Measure the size of the nipple on the vacuum unit.
2. Should be a metal pipe coming up from trani, measure diameter.
3. Measure size of valve that hose connects to on booster.
1. Measure the size of the nipple on the vacuum unit.
2. Should be a metal pipe coming up from trani, measure diameter.
3. Measure size of valve that hose connects to on booster.
I have heard people argue that fuel line is designed to hold pressure, while vacuum hose is designed to hold vacuum, but this argument has always struck me as ridiculous. Yes, fuel line is designed to hold pressure, but you can tell just by feeling it that it is much more rugged than vacuum hose, and will hold vacuum even better than vacuum hose. Personally, I think that vacuum hose is used by the manufacturer because: 1; it's cheaper, and 2; it is maybe a little more flexible than fuel line.
As for which size to use, that's a pretty easy question to answer: use whatever size line that fits the nipple nice and snug.
Scott
