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Trying to figure out which carb is on my 78MY. Bought the car recently. Identifying numbers that I can see are 1405 2597 and 8867.
Also, can anyone tell if the water pump is the short or long version? Looks like short, but I’m not positive. Appreciate any help!
You need to get that carb off of that intake.....see that 1" spacer under it....? That is probably the worst thing you can possibly do to your fuel system and is a straight up epidemic in the vintage world. People bring this setup to me frequently over the yeras and will refuse to work on the car until one of two things are addressed......I tune a LOT of old cars and this adapter makes it impossible to do correctly.
That spacer "adapts" the square bore flange carb to a spread bore intake manifold. The mismatch on the primary side to make this possible is terrible and it blocks off the half of the throttle blade that "tips in" which on a a correct setup....the air would just slide down the blade as it tips back....on your setup, the air has nowhere to go and now the vacuum pulls the air in and around the raised part of the blade going up during tip in......this creates an awful turbulance in the throttle bore and makes it impossible for the boosters to dispense fuel properly.......it also creates a lot of reversion.......the engine will never run as it should.
Pull that carb and sell it....or keep it and swap the intake with a 2101 performer or equivalent. If you decide to get another carb......look for a good used Q-Jet core or a spread bore Holley replacement.
Here is one of my favorite photos of this mismatch on a 318 Mopar...it really gives you an idea of what I am talking about........the blue circles are where your throttle blades tip in.......zero airflow in that area, the most important area to create carb signal.
From: At my Bar drinking and wrenching in Lafayette Colorado
Not to mention that the Edelbrock 1405 is a re-pop of an old 1965 Carter AFB, which was deemed to be obsolete by GM after the 1966 model year. It was simply a horrible carb for use on anything resembling a performance engine. Through the magic of Edelbrock Marketing, that horrible, obsolete carb has now become a "performance" carb. In fact, it's still the awful carb it was in 1966, and still belongs in the shop trash dumpster, which is where we used to throw them... Find a good, used, rebuildable 1978 Q-Jet and have it built properly. It will run circles around that horrible setup, especially with that adapter plate.
Lars
The carb and spacer will be in the trash in no time. Planned on a carb swap anyway. Needing a 4150 blow through carb with what I’m planning. Also needing a long snout water pump. But to my understanding, there’s long, short, and a Corvette style. So not sure on what to do there yet. Obviously electric fans with be needed.
Yes your Corvette uses a Corvette water pump, not a long or a short. None of your belts will line up properly with long or short style pumps. If you go to a long pump and figure out a way to move all accessories forward. And as you said electric fans. Biggest issue you will have is relocating the power steering pump. Cause I'm pretty certain you won't have much room to move the powersteering pump forward.
Not certain what your up to but if you could use the Corvette waterpump somehow it might help. The Vette pump is just a tad longer than the short pump.
If you need a long style pump, pulleys, P/S, A/C....etc......look at ANY small block besides the Vette from the mid 70's to the mid 80's......
Keep in mind though if you use the long style brackets and pulleys.....the Alt and A/C are swapped......
Help identifying carb?
