Carb selection help

[LR1970]

Hi, I'm full of questions at the moment, but it I don't get things right the first time my wife will nag me to death!

I need some suggestions with what carb to use. My car will be as follows:

67 Coronet R/T
RPM intake
Port matched intake and mild head work
Comp Cams EX268H 268/280 Duration and .477/.480 Lift
Headers and 2.5 inch exhaust system
727 with stock convertor and shift improver
3.23 rear gears
27 inch tyres

I'm thinking of using one of the following in a vacuum secondary:

Holley 750 3310
Holley 770 Street Avenger
Edelbrock 750

Maybe a 650 Mec secondary will be ok? The car is just a cruiser.

Thank you FBBO

 

[383man]

What siz eng ? 440 ? And what heads are on it ? Ron

 

[LR1970]

Sorry, 440 and stock heads. 915 heads I guess, I will know for sure when I pull the engine down.

 

[451Mopar]

I can make you a deal on a lightly used Holley Ultra Avenger 770 carb with the blue colored base and metering blocks.
Had it on my 505" stroker for about 200 miles, then I switched to EFI.
It Cost me $530, and I'll sell it for $400.

Link to summit an the carb:
http://www.summitracing.com/parts/hly-0-86770bl/overview/

 

[383man]

I would most likely use the 750 Holley but really anyone of the thee carbs you listed would work ok. I would not use the 650 but it would run ok with it course it may not be as fast and as strong as the other three that have more CFM. Ron

 

[Charger686970]

I would give Patrick James at pro-systems carbs a call and talk to him. I gave him the complete break down of my motor and sent him my holley 750 dbl pumper and he built it for my combo. It is now a 780cfm dbl pumper. The carb runs awesome. Even bolted it on my brothers cop car and the tone of the exhaust changed and the car felt like it gained 40-50 horse. You don't need to send a carb they can build one from carbs they have there. Price wise they are the same as ordering them from Summit or Jegs. Other then setting the floats and air fuels that was it. For info I gave pro-system every detail about the motor, tranny, rear end gearing, header and exhaust size, tire size intended use of the car and what gas I was going to be running in it and approx. weight of the car. You will get a print out of what is in the carb and it will show you what jet sizes would be lean and rich on both primary and secondary if you have to change them and they keep it on record so if you call with a question they can look your carb up. Having them build my carb took a lot of the tuning time out because it was ready for the motor combo.

 

[WileERobby]

I would most likely use the 750 Holley but really anyone of the thee carbs you listed would work ok. I would not use the 650 but it would run ok with it course it may not be as fast and as strong as the other three that have more CFM. Ron

I agree. It would come down to which carb you'd be proficient to tune.

 

[Meep-Meep]

Carbs like vacuum, or a strong signal to work properly, so lean toward the smaller size. The 750 on a mild built 440 will work very well but it's best you get a 750 that has a street use calibrated metering block. This does not mean race use like a double pumper.

 

[sleepar]

Vacuum secondary

 

[UKPlymouth]

I'm a convert to the new Street Demon 750 for everyday driving.the Thermoquad style one. Drove smooth out of the box, picks up from idle well and gave me much more idle vacuum than my Holley ever did.
My 750 is on a 340 Roadrunner and is not too much carb. The spread bore application is designed to pick up a good signal from the intake for street driven, non race cars.

 

[rumblefish360]

I was going to suggest a big TQ. But that new Demon is actually an excellent idea.

 

[snakeoil24]

Get yourself a Quick Fuel 750 and you will be very happy. Well made and better design then Holley.