Dbeck002

would aftermarket heads and intake help gas mileage? i dont see why it shouldnt because its letting the engine run more efficiently, less strain to pull air in.


remark: remember im talking about cruising conditions, not WOT and stuff, i know that consumes more air and fuel.

91hatchgt

I wouldn't think so, because although it is breathing easier, it still takes in just as much fuel.. It just makes it burn more efficiently, maybe i'm wrong... Just a thought.

luckythirteen13

my milage is the same now as it was before i did my heads

Monch

you are right, it does benefit, however the strain that you are relieving is relatively minor (compared to the crappy thermal efficiency of the motor to begin with) and so your gains in fuel economy would be minor.

EGSRacer

On one of 427SC kits I used a base 92 5.0 plant to start with. When I replaced the stock heads with FRP aluminum ones and went from stock to GT-40 intake upper and lower (all ported and polished btw) I saw a +2 mpg difference. Hope this helps.

Monch

thats a pretty good gain, but i'd be worried about running a bit lean if i picked up gains like that, if you were not then more power to you.

roundman

they can but it all depends on how you drive it. it's not so much the strain in pulling the air in but how much more efficient you can make the engine work as an air pump which is what it really is. with the headers you already have you have helped on the exhaust side so reducing flow restrictions on the intake side should yield some gas mileage improvements also if you don't change the way you currently drive now as the engine should be able to make the power needed at a slightly lower rpm if it can breathe better.