Re: [Chevelle-List] RE: carbs.

[MICRLASER]

Generally it is best to run a dual plane intake on a street motor unless you are pushing 600 horsepower.  I run the edlebrock performer intake and a q-jet on on the 350 in my dailey driver Cutlass.  It averages 15-16 miles per gallon on the highway with 3.42 gears running around 75-80 mph.
The 454 on my Chevelle is running an Edlebrock Performer RPM and a Holley 3310 carb.  As far as gas mileage on that car is concerned, it gets about 15 mpg on the highway running at 3800 RPM's at 80 mph.  Not too shabby for a 500 horsepower big block and 4.10's.
The best carb I ever had was the Q-Jet on the original 307 Olds motor that was in my Cutlass.  It had the computer carb on it, but I ripped it off and rebuilt one off of a 79 Delta 88 that had a 350 in it.  That carb never hesitated once, stuck, bogged, or any of those other Q-jet problems.  The one on there now is a POS.  It hesitates, bogs and cuts out when I wind out 1st gear and hit 2nd gear at 5200 RPM's. 
I may have to put the Olds carb on the Chevy motor in there now.  I wanted to throw a Holley on there but since Q-jets are all spreadbore and the Holley isn't, I would have to run a spacer/adapter so I could have brakes and fit the suare bore Holley to the spreadbore intake.  Then there is the problem of hooking up the detent cable and getting a smaller air cleaner to clear the hood.

Tom

PS:  any carb will get ya decent gas mileage if you keep your foot out of it ;-)