smoked

I was wondering what kind of gas millage i would get from a mildly built carb'd 355 with a 700r4 tranny.. Cam is gonna be around 224/230@50 with the lif being under .550 on both intake and exhaust..Gears are going to be 3.73

Joshiedoom

iTrader: (4)

Depends on the weight of the car and how much you stay outta the gas. I got around 14mpg max with my blazer and that similiar setup

smoked

Its goin to be in a '91 Camaro RS. Its got a TBI 305 in it now, but 170hp at the flywheel just isnt goin to cut it. Looking to make around 300 horse and still get decent mileage. Can the 305 make that much power with out putting alot into it?

ZONES89RS

iTrader: (25)

Nope the 305 needs a bit more. The car should get about 16 give or take how it is set up. I have seen 18-22 carbed, keeping my foot out of it that is.

XtremeModifier

355 should be around where mine is ... 12mpg. Granted, I was getting on it occasionally and have a stroked 355, but since I had it on the street for 1 week after paying but before transferring it to my name (bought from a friend, so he let me have it on the street for a week until I could work a few bugs out) I was still being very light on it, since I didn't want to get pulled over.

slow95z

iTrader: (33)

good luck with that tranny! it won't hold for long without putting a lot of money into it. and then it is still going to be weak.

bluebeast

iTrader: (1)

a carb small block motor if set up correctly can get really good MPG's..... alot of guys are running big gears with A3 trannys and then will have the carb all out of whack and wonder why they are getting 8mpg and then say all carbs suck for fuel economy..... i have a freind who gets 28 mpg in a 1967 camaro sbc carb motor with a 355 gear and tremec 5 speed.... i know he has a decent gear and tranny for fuel economy but still some guys seem to think a carb motor will never get as good as an EFI car and thats not true if its tuned properly!!!!! jake

ZONES89RS

iTrader: (25)

Oh yea, i am geting 18-20 right now and my AF ratio is like 12 to 1, i am jetting it down today.

XtremeModifier

idk why people bash the 700r. It's actually a very solid transmission for an automatic - and there's quite a few LS1Tech suppliers (see: right side column) that build race 700r4's, plus lots of shops that'll build one tailored to your vehicle and what you want. Of course, there's always the good ol powerglide if you're gonna build a big motor.

trailwart

my s10 with a 355 and 700r4 gets 20-22 on the highway cruising at 60mph. around town i see about 17mpg. my last tank was an all out beat down on the truck and i seen 12mpg.

comanten123

iTrader: (24)

i was getting 17mpg with a 700r4 on a 383 stroker motor. so i would say 18mpg. on the highway

jmd

iTrader: (4)

I drove one of my 83 SSs w/ Vortec heads on a 355 w/ the stock ECM and Q-jet, late 80s 700-R4 and 3.42 rear; stock height ~26" tyres. From Phoenix to Abq., I knocked down 25mpg. Prior owner had that carb tuned well; it was one I loaned him, and I'm still using it on another car.

DarkJuggalo

iTrader: (6)

i had a 355 in my 91 RS, t-tops, fiberglass hood, 4.10 gears, posi, full stereo system, original interior, and some other stuff like sub frames and what not and i averaged(driving like a grandma not WOT every chance i got) around 13-15 mpg. 4th gear locked up cruising 55 i got 18 mpg