alright what kindaMPG do u guys get with a 650CFM carb and then u guys with the 750CFM what r u guys getting MPG

 

im running a 600cfm vacuum secondaries and im getting about 14mpg and 27 on the high way

 

nice what kinda power u makin

 

not sure really ran a 15.1 with the ebrake on half way and a bunch going wrong with the car should be in the low 14s high 13s in march

 

sweet any1 else

 

bump

 

15 highway about and 10 in town with a 650 and 12 highway and 8 intown on a 750 but i run a 600 on my car unless i race it...

 

i would just like to say that even for your 351 that u plan to build a 750 carb would still be a little big, a 700 is probably the biggest you should go. if you consider i run a 750 on a 390 fe big block.

 

ya im just trying to figure out what im going to do

 

If gas mileage is of any concern, don't even use a carb, stay EFI.
It's also a fact of life that as more power is produced, more fuel needs to be used. The amount of fuel used in units will be referred as BSFC (if I remember right) on a complete dyno test chart.
Take a look at one someplace for a 300HP engine and then compare that BSFC to one for a 400HP engine you'll see what I mean.......