Carb Question

[Quackaddict]

Redoing my motor and the Q-jet that is on there is in sad shape. Been looking around and have found 2 that I am really interested in. But I am a carb virgin here so I don't really understand what to look for and what to stay away from.

One has electric choke I am not sure on the other......but I don't even know if I have electric choke??????

My Motor: 1978 454, 781 Heads, headers, Air gap intake, HEI.

Carb 1 - 850 CFM Holley Double pumper, supposedly has been already tuned on a running motor for max performance etc, etc

Carb 2 - 750cfm Edelbrock 1411 series pretty much brand new out of the box.

There is quite a difference in price which isn't an issue and I am not looking for a edelbrock vs Holley arguement.

The issue I am trying to figure out is would one be better for the motor or would my motor since kind of stock not benefit from an 850cfm or is 750cfm to small those kind of issues.

[prostreetC-10]

Actually, this is a pretty easy one. I don't care if your motor is a 283 or a 454. If it's basically stock, the Holley 850 is ABSOLUTELY OUT!!!!

You would have a better chance of getting away with the ED 750 but it's going to more than likely be too big too. The 1411 differs from the 1407 in that it's supposed to be a big block calibration but I really think they have just leaned it out a bit over the 1407 750. You would acutally do much better with a 600 Holley OR Edelbrock carb. You can even go smaller than that if the motor is bone stock. Either way the 850 is completely out (if it is in fact an 850). There are a lot of 650 Holleys out there being sold as 850+ because the people don't know a thing about Holleys so they take a guess. Stick with the 600 or slightly smaller cfm range and your gas mileage along with streetability will be about the best it can get.

Once again....you can get away with the 750 because it is a 454 but if you are not getting a smoking good deal since it's almost new, you might want to look at a slightly smaller carb. This is coming from a guy that not only builds them but has also tried both a 600 and a 750 on his warmed up 454. The 600 was MORE than enough fuel.

[Quackaddict]

My motor is a 454 big block, with headers, aftermarket intake and possibly roller rockers. The 1411 is a pretty good deal. The holley was a double pumper. Thanks for the advise I guess it was easier than I thought.

[prostreetC-10]

Don't quote me on this becaue my P/T buiness is strickly Holley but I think the difference between a 600 to 750 holley is more dramatic than a 600 to 750 Edelbrock. If it really is a good deal, then go for it. You do have the cubic inch on your side for the 750. You can always sell it if you get into it right and get a smaller carb.

[mclairmo]

I vote for Carb 2 out of the choices presented.

[Leviticus]

Originally Posted by prostreetC-10

Actually, this is a pretty easy one. I don't care if your motor is a 283 or a 454. If it's basically stock, the Holley 850 is ABSOLUTELY OUT!!!!

You would have a better chance of getting away with the ED 750 but it's going to more than likely be too big too. The 1411 differs from the 1407 in that it's supposed to be a big block calibration but I really think they have just leaned it out a bit over the 1407 750. You would acutally do much better with a 600 Holley OR Edelbrock carb. You can even go smaller than that if the motor is bone stock. Either way the 850 is completely out (if it is in fact an 850). There are a lot of 650 Holleys out there being sold as 850+ because the people don't know a thing about Holleys so they take a guess. Stick with the 600 or slightly smaller cfm range and your gas mileage along with streetability will be about the best it can get.

Once again....you can get away with the 750 because it is a 454 but if you are not getting a smoking good deal since it's almost new, you might want to look at a slightly smaller carb. This is coming from a guy that not only builds them but has also tried both a 600 and a 750 on his warmed up 454. The 600 was MORE than enough fuel.

Very good advice here^^ nice work Prostreet.