A few simple questions for some.
I have a 69 BB (convertible) with a 750 holley.The engine runs very rich andit seems that Ihave made a futile attempt to adjust the carbair/fuel mixture.I will end up replacing or rebuilding the carb at some point, but didn't know if anyone had a quick fix or proceedure to adjust the carb? I just need to get it to the point that Ican enjoy the ride without getting gassed out?[:-]

Also, I have tried to figure out if I have a 396 or 454? I tried to research the numbers on the block and could not match them up. Are there any tell tale signs I should look for. The reason this came up is when I replaced my tranny the I was told the the engine is internally balance and I could use a standard fly wheel. That definately was not the case and I had to use my old (balanced fly wheel).

 

There is a post on the front page for numbers. You can find any number you want on that one. It leads to several sites with engine, head, body codes, you name it.

As for the original question. It's a Holley 750 cfm carb. Is it a double pumper? 2 float bowls, one at either end. It will have inlets for 2 fuel lines as well. Or is it just a standard carb?
Reason I'm asking is that unless you really know how to tune a double pumper, you're in for some headaches. I suggest picking up a video or book (video is faster to learn). Then do it or swap it out. I ran a double pumper on my '67 for a coupe weeks. SUCKED! I yanked it off and bolted a Edelbrock 750cfm Performer series carb. They have a tune kit for it that is real easy to change the jets and needles. And it ran like a charm. Too bad I sold the car 6 months later. I saved the carb though and just sold it to a guy in Bakersfield, CA for $125 with the kit.

That's just my experience. Do what you want.

 

Yep, It's a Holley double Pumper, two fuel lines and two float bowls. Your the second person that said good luck with the Holley andsuggested the Edelbrock.
Thanks for the info

 

Dual fuel line inlets only tell its a 650 or larger carb. A double pumper has two metering blocks. Holleys work great if you know how to tune them right. You definetly don't need to replace a good carb but it might need a rebuild. Your needle and seat assembly might be sticking open causing it to run rich or your float is set too high, causing the needle and seat to stay open. Remember when adjusting the mixture screws that turning them left runs richer and right is leaner.

 

how long has it been running rich

 

It has just started recently. The last few months. When I purchased the car last year it was fine.