Don't know if this is a repost so sorry if it is. I was wondering if there are any mods that can be done that would add to performance but at the same time save some gas (is driven economicly). I already put in an intake but just wondering if there are any others.

 

Intake, exhaust, tune

 

i get better gas mileage now and i'm stage 2 with a 2.9 and fully bolted. that's of course assuming i'm driving normal. i average about 27 mpg or so, but if i try i get close to 40 on the highway and over 30 city. but i normally get bored with trying to get good mileage and that all goes out the window and when i get that good mileage, it's not driving like an old man, it's over the speed limit on the highway and the speed limit on normal roads. the biggest thing that will help you is coasting to stops instead of using the brakes, and accelerate a little slower. idling KILLS your mileage, so you want to be stopped as little as possible. driving at 2 mph is better than being stopped.

 

...this is the 2.4 section!!!

 

and? i explained how driving a little differently will help regardless of mods. it applies to all models, as well as all cars.

 

...I thought you were suggesting he should get stg 2

 

woops maybe it was a confusing post what i meant to say is that it's more the way you drive. but bolt ons will help if you can keep your foot off the gas.

 

With the turbo, im averaging 44mpg @ 70mph with cruise control.

However, when in stop/go (ex. city streets), i can expect under 10mpg.



Anything performance related, excluding engine internals in theory should increase hp/tq while also improving your mpg. Why? If you allow the engine to breath(More HP/TQ due to the increased air), you also allow the engine to not work as hard when cruising (Cruise Control).

I have also found that back when I just had an Intake/exhaust, 87 octane netted me probably mid 30's mpg, and with 91/93, i was in the 40's.

 

I'm thinking of getting an exhaust next but it's gunna void my warrenty. Now quick quesiton about exhausts...I know a 3" on the 2.4 that is stock is too much but I'm just wondering the logic behind it. I'm still in the process of learning about this stuff lol. And what would be the biggest exhaust to suggest putting on a pretty much stock 2.4?

 

..just go with a 2.5", 3" is to big and loud and will not benifit you any

As for your warranty I wouldn't work to much about it, you're more likely to suck up water w/ your intake then to do any damage with an exhaust.

 

Now if I were to get a 2.5" exhaust I should probably stick with a 2.5" header and downpipe when I do eventually get them?

 

yes

 

How about methyl alcohol and water injection using a progressive controller? I've been considering AIS's NA system -- see http://www.alcoholinjectionsystems.c...c25/index.html

If you set the controller to start injection under light throttle application, you should see improved fuel mileage since less gasoline is used as the result of the increased torque from the water and alcohol. Typical NA HP improvement is 10% to 15% or about 15 to 20 HP on traditional NA gasoline engines producing 146 HP like a LE5. The E67 ECU may actually LEAN the injectors to compensate for the enrichment by the methyl alcohol and lower IATs which would result in better gas mileage. You want to be 1st?

 

Wouldn't it be bad to make it lean though?

 

the exhaust has to have a certain velocity, it has to get out as fast as the engine is pushing it out. so imagine it like this. the engine pushes it out, and then it has to go through the exhaust. if the exhaust is too big, the air flow slows down. the whole point of getting an exhaust is to move air faster, not slower. so you want to get a pipe that is big enough to not restrict the flow, but small enough to keep the velocity up.

too small and the air can't move through the pipe fast enough. too big, and the air just kinda dribbles through the pipe, creating turbulence which = bad

 

Don't speed? Take out unneed weight, and also put proper air in tires, and don't jackrabbit it at lights, even more when there are no cars behind you. Doing just these things I have hit 34 mpg and I have an auto SS 2.4

Plus I have injen CAI, shiftplus only on week before track day, gmpp touring exhaust and header.