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Steamboat 16

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Discussion starter · #1 ·
What are some ways that i can get better gas milage with my 98 Jeep grand cherokke 5.2L V8 that won't cost me too much and that will improve power also. (I already have a KN air filter on it and am getting 2.5 inch pacesetter exhaust)
 
That's tough man, my friend's got a 98 w/a V8 and he gets around 14-20mpg - so I'd say make sure your tires are properly inflated and aligned, (misaligned steering wheels also cause drag not many know that) and watch your right foot. Oh yeah, I sell truck parts and it kills me to see people install 100lb trailer hitches and not use them, stuff like that that weighs down your car kills gas and I don't know why they don't take'm off. I dunno but I wish you good luck and I hope gas is "cheap"er in your neck of the woods lol!

(I'd recommend checking your O2 sensors too, they can hurtcha and so can your fuel filter)
 
Discussion starter · #3 ·
Thanks man for that advice about keeping the weight down, i wouldn't have thougt of that on a SUV, how do you think headers would affect the milage along with the exhaust? apreciate any help you can give.
 
Steamboat 16 said:
Thanks man for that advice, how do you think headers would affect the milage along with the exhaust? apreciate any help you can give.
Well in theory headers will yield a more efficient exhaust flow thereby freeing up some drag enflicted on your engine, promoting BETTER gas mileage... you should also note that headers free up a lot of hp in most cases and more hp = faster acceleration = WORSE gas mileage. IMO, it's a matter of driving style; ie, put on some nice longtubes but watch the right foot and g/m should improve noticeably.
 
Discussion starter · #5 ·
well thanks for the help, my jeep really isn't my car that i drive fast, thats for my mustang, the jeeps just for going out on dates with (Came with $2,000 sound system, Leather, and sun roof, really impresses the chics) and getting around town with in the winter. The headers i'm looking at are edelbrock long tubes so thier pretty good. But just so i know about how much power will the headers add?
 
Steamboat 16 said:
The headers i'm looking at are edelbrock long tubes so thier pretty good. But just so i know about how much power will the headers add?
Anyone feel free to correct me if I'm wrong, but typical power gains on a full exhaust are around 15-40 hp, depending on the size and quality of the tubes etc., and other factors such as engine performance (ie. other mods), size, etc. I'd imagine 10-12 hp from headers alone and don't forget about your midpipe... a good x-pipe alone (imo better than h-pipes) can yield more hp than bigger tubes + headers + hi-flow mufflers combined.

Not that I've ever actually heard of people doing this - but if you have those bike/kayak/cargo racks up on the roof of your Jeep, they're causing aero drag (same principal as keeping your windows up when over 40mph) and will help your mileage if removed.
 
Horseshoeing said:
keep you windows up and don't turn on the air.
There was actually a study of aerodynamic drag on vehicles conducted by Ford Motor Co. down in AZ about two years ago and a few people from Embry-Riddle Aeronautical University, including myself, helped test certain "gas guzzlers" for fuel efficient modes of travel...

A myth that needs to be broken is that it is better on gas to roll down your windows on the freeway to keep the a/c off. Ford backed our test results and is now posting helpful gas-saving tips in magazines across the US. Anyway to break the myth - rolling down your windows causes under 9m/s(s) (ie, the force of gravity :blah ) when traveling at speeds under 40 mph and is therefore beneficial to have your windows down rather than run a/c at those speeds. However above 40mph, it became very detrimental and hurt our test vehicles over 5mpg when compared to having the windows up and the a/c on.

sorry if it got kinda long and confusing there, I'll stop now :wave
 
A better flowing exhaust and a better flowing intake would help ya a bit...
 
Discussion starter · #15 ·
HOw would u/d pullies affect my engine life and my sound system though, PS. horseshoeing they are suv's just to let you know
 
Anyway to get the engine to breathe is a way to improve EFFICIENCY, and thus, gas mileage.

Might I suggest a full intake/exhaust, along with a set of ported heads, properly inflated tires on a set of lightweight rims.


What are your driving habits? Sitting at a redlight awaiting the afterburn take off? or do you grandma your way around town in it?
 
Steamboat 16 said:
HOw would u/d pullies affect my engine life and my sound system
U/d pulleys would net a few hp to the engine, but can be detrimental to your sound system, however a system big enough to worry about this probably needs to be run on its own battery supply anyways, so unless you've got all of Best Buy's subwoofer collection in your back seat, I wouldn't worry 'bout the negative effects of U/d pulleys.
 
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