I currently have a Holley 4150, which is way too much carb for the pathetic engine that I have. I am looking for a suitable replacement (250-300cfm) that would bolt up to the intake I have, Holley Street Dominator. If anyone has a smaller carb and would be interested in a trade, let me know. I am not looking for power right now, just a more fuel-efficient carb so I can drive it without breaking the bank. I plan on dropping a big-block in later, so I will just buy a new high-cfm carb later.

 

The "4150" is available in several different sizes, 4150 doesn't tell anyone much. What's the cfm rating? If it's the 650, then it should be fine and maybe you just have a tunability issue.

 

I have no idea what size it is, a friend of mine told me its a 750cfm, and I should get a smaller one in the 250-300 range. I've posted on here before trying to find out what it is, and nobody here knew the size either. I get 7mpg... I'd like closer to 15-20 'til I get my big-block in it.

 

Yikes! I guess so. If it's a 305 motor, yeah, I'd think 750 is too much.

I'm no Holley expert, but I assume there is a model number on it somewhere that you could check against the numbers on Holley's site. Or email/call them and have them tell you how to tell - then you'll know what you have.

Is it a 305?

 

It's a 350, bored .030 over. Old block, junk heads.

 

If it's a 750 cfm carb, then you should be able to tune it fine for a 350, although a 600cfm would be better. I get 17mpg on my old junker 350 and auto tranny with 3.42 gears. 200 - 350 cfm is going to starve that motor, you need 500cfm minimum.