Hey guys i want my MPG! haha
im taking my 302 block in for a rebuild next week !
do you guys have any recommendations to building something decent on gas?
Is it possible to reach 20-25 miles per gallon with a carburetor?
thank you

 

you can get 20-25 on the high way with a five speed and good gears out back.

the carb will work against you tho.
if your that concerned about it, go EFI

 

I already have the T-5
i want better gears out back as well, but im low on cash[:@] haha
i have an edelbrock performer 289. Im planning to install it on the block with a holley 2 barrel...
should i go this route or should i just adapt a 4 barrel?
will a better flowing exhaust help my mileage?
thanks

 

Actually... a stock engine is roughly 80% efficient. When you build a performance engine, the volumetric efficientcy goes up, therfore allowing you to make more power on the same amount of fuel (or the same power on less fuel, just depending on how you look at it). So, what I would do, is build a well flowing engine with a small cam.Using a stock (or close to stock) cam will allow you to make you power lower in the RPM range, and you will therefore burn less fuel to make your power.Clean up the stock heads (smooth them up) or buy some small aluminum heads, and add that good intake and a good exhaust with headers. A small 4 barrel carb wont hurt you (get a 500 cfm vacuum secondary). Build it with about 9:1 compression so you can run it on regular 87 octane gas. Then put a 3.25 gear in the rear end with some26-27 inch tall tires. That will gear it just rightfor good mileagesince you have the T5. OH, and the number one way to get good mileage out of any engine is to KEEP YOUR FOOT OUT OF IT! Lol, this will help a lot by itself. Like was stated above, for the absolute best mileage, go with a mass air fuel injection setup out of a Foxbody. But if you don't want to go that way, I still think you could see 20 MPG around town wth this setup and about 25-28 MPGon the highway.

 

awesome! just what i wanted to hear!
thanks guys!

 

i don't get:
"i have an edelbrock performer 289. Im planning to install it on the block with a holley 2 barrel... "
the performer is a 4barrel intake manifod and will not fit a 2barrel carb ?!

 

thats very true, but you can buy an adapter plate that sets on top of the intake manifold and coverts it to a two barrel. basically it covers one of the openings and it comes intergrated with shorten screws to allow for the 2 barrel to be placed perfectly on top. But now that tyler says i can use a 500 cfm 4 barrel carb. without affecting much of the gas mileage there is no need for me to buy an adapter plate and run a smaller two barrel unless one of you guys oppesses his opinion. haha j/k
thanks

 

if you get a vacuum secondary like he suggests they are only bpulled open when the engine needs it which means you have your foot down. so ya. i'd rather go with a 500cfm 4b as well. And maybe occasionally you will like putting your foot down ...

 

If you like lower MPG without compromising too much performance, Do the little stuff too: tune your carb, check for low tire pressure, change/clean your air filter often, and keep your windows closed on the freeway. -5# psi in the tires alone can rob gallons of gas. BTW, The trick to consistently correct tire pressure is 1. Keeping a gauge in the glovebox. 2. Actually using it once in a while.

Carlos

 

Using the propper 4bbl carb can easily improve MPG over a 2bbl carb. Why? because the 4bbl's primaries are a lower CFM than the 2bbl, less air flow, less fuel used.Staying onthe 4bbls' primaries will also increase intake vaccum, keeping torque up, better performance. TILL Ya Put Yer Foot In It! The 4bbl is actually optimised to workmore efficentlyover a broader RPM range than the 2bbl.
Everything else being equal the overdrive tranny is still you best MPG investment.