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From: At my Bar drinking and wrenching in Lafayette Colorado
All ports on that carb are manifold vacuum except the port coming out of the throttle plate on the forward passenger side at an angle (with the black rubber cap on it). That port is ported vacuum.
Lars
From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by Budryzer
Just to clarify for me please? The stock hose connection as picture in the OP's post is manifold vacuum?
TIA Lars
The OPs hose is not connected to the stock location. It is connected to a manifold vacuum port normally used to supply vacuum signal to the A.I.R. pump diverter valve and to the EFE through the manifold thermal vacuum switch. The stock vacuum advance location is the forward, driver's side port in the float bowl, which is also manifold vacuum on that carb.
Lars
Thanks Lars! I see he is missing a vacuum pot/diaphragm (above and fwd of choke) that has a link that goes to the secondary butterfly's. What effect does this create?
TIA
From: At my Bar drinking and wrenching in Lafayette Colorado
He is running an incorrect Heavy Duty Truck version of the Q-Jet, which uses a rear choke pulloff only. That 1-ton truck carb does not use the standard Corvette/passenger car forward pulloff, and is an ill-suited carb for his application. The rear pulloffs are also notorious for leaking, seizing, and failing, so there's a really good chance that it's defective as well... The OP would be well advised to locate a correct vintage Chevy passenger car carb for his Vette.
Lars
Lars, thank you sincerely for your comments on.my carb. I knew it was not a correct carb, I even knew from your papers it was a truck carb, but what I didnt know was how potentially bad it was. I will start my search for a correct carb. Anyone have a correct 79 L-82 4 speed carb lying around??
From: At my Bar drinking and wrenching in Lafayette Colorado
Pete -
If you send me an e-mail request, I can send you some info that may assist you in the search for a "more correct" carb. You are going to be limited to a 1978-1979 Chevy carb due to your bowl vent/canister emissions hoses. Pre-'78 carbs do not have the bowl vent provision, and it would be nice the have a carb with all the correct hookups, whether you intend to use them or not.
From: At my Bar drinking and wrenching in Lafayette Colorado
Good, rebuildable cores pop up from time to time - you just have to keep looking and watching and snag the good ones (and avoid the crap ones...). That implies you can tell the difference, and I can assist you with that.
Lars
Where to pull vacuum from
