77GCSX

The new one doesn't have some of the vacuum ports. The main one I'm concerned about is the evaporator line. Do I REALLY need this or can I do away with it.

The others I can tee into.

Thanks, Paul

MDchanic

Perhaps more information would be helpful:
Year of car?
Year of engine?
Displacement?
Original or modified engine?
Year, model, and engine that the new carb was removed from?

- Eric

77GCSX

73 Delta 88, 350 non modified. Bought a carb from National Carb out of Florida. Item number matched what I have but there were some differences in the vacuum ports. The main one I'm concerned about is the evaporator line. There is only one other line with out a port but I can tee it into another. All the other lines are there.

MDchanic

Hmmmm...

I'd have to see pictures of both carbs to offer a really intelligent comment, but

It sounds like they essentially sent you the wrong carb.

A '73 should (apparently) have a port for the evaporative canister, and should also (probably) have a specific EGR port (the QuadraJets did), as EGR vacuum is taken from a slightly different place than either manifold vacuum or "ported" vacuum for the vacuum advance.

If you want to use that carb., you may have to cap off the evaporative emission system, and possibly the EGR as well. A non-EGR carb should run fine on an engine with EGR disconnected, whereas disconnecting EGR and using the original carb will result in a slightly lean mixture.

- Eric

77GCSX

So far so good! I believe I'm ahead of the game with this new carb. The only problem I have is a quarter pedal bog, both from a stop and while cruising. I'm trying to tune it by the exhaust smell and sound (idle). If you or anyone else has any other ideas for tuning I'd like to hear them. This is my first real attempt at tuning a carb.