Getting better MPG's... - Great Lakes XJ

xjryder

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Posts: 470

Date: Jul 28, 2008

RE: Getting better MPG's...	Permalink

Ok I need to apologize for my previously post I was mistaken when i said mid to high 20's I went to my folder with all my maintanence records and I was thinking It was 356 miles on a tank but it was 317 (OOPPPSSSS!!!!!) I am running very narrow tires 9.5 now, but that was when I was running 31 Geolanders, as for speedo gear nope stock gear, 8.25 rear, on a 15 gallon tank, drove to Salem ,WI and used 1/2 tank of gas, in NOV I will be driving down to Big Pine , Flo, I will document my findings with these 33x9.5, Maybe I made a mistake when I figured this all out, I am honestly positive I figured that you take the miles you drove on 1 tank of gas to the 15 Gallon tank and so I got 317 miles off 1 tank (HIGHWAY) and divided it by 15 and got 21.13333333, so if I change some speedo gear, get a high flow thermo housing , BRX hoses, high flow water pump, and get a performance aluminum radiator, power programmer, accel tune up kit, and everything else in the jeep parts catalog LOL IT should do the trick -- Edited by xjryder at 13:46, 2008-07-28 __________________ To build something that can run over the idiot driving 45 in the passing lane ,Now Thats Talent!

ChevelleSSLS6

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Date: Jul 30, 2008

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JP magazine is doing a project mpg xj. It'll be an interesting read.

But...
I've heard a 97+ XJ intake manifold will improve power (more efficent airflow) and should therefore use less fuel since the gains are made by reducing pumping losses. What are pumping losses? The power the engine uses to pull air through the air intake hoses, intake manifold, cylinder head, and out through the exhaust. Therefore, the less power used to move air, the more efficent the engine should be. I wonder if the power steering pump on the older XJs will fit on the newer manifold.

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My Fleet
1996 XJ "Snowball"- 3.5" lift, bunch of little mods. I hate pegleg rear axles!
1974 AMC Javelin "Jade Grenade"- 360v8, 4sp, green inside and out. Underfunded Project.
2009 Kawsaki Vulan 900 "Rocket III"- Summer DD

LEAD_NOT_FOLLOW

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Date: Jul 30, 2008

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ChevelleSSLS6 wrote:

JP magazine is doing a project mpg xj. It'll be an interesting read.

But...
I've heard a 97+ XJ intake manifold will improve power (more efficent airflow) and should therefore use less fuel since the gains are made by reducing pumping losses. What are pumping losses? The power the engine uses to pull air through the air intake hoses, intake manifold, cylinder head, and out through the exhaust. Therefore, the less power used to move air, the more efficent the engine should be. I wonder if the power steering pump on the older XJs will fit on the newer manifold.

t's actually the '99-01 intake manifolds as they are designed differently (more curved and larger ports).

And yes, they are a bolt-on swap for any 91-98 XJ.

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ChevelleSSLS6

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Date: Jul 31, 2008

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LEAD_NOT_FOLLOW wrote:

t's actually the '99-01 intake manifolds as they are designed differently (more curved and larger ports).
And yes, they are a bolt-on swap for any 91-98 XJ.

Thanks for the correction smile

__________________

My Fleet
1996 XJ "Snowball"- 3.5" lift, bunch of little mods. I hate pegleg rear axles!
1974 AMC Javelin "Jade Grenade"- 360v8, 4sp, green inside and out. Underfunded Project.
2009 Kawsaki Vulan 900 "Rocket III"- Summer DD

Topic: Getting better MPG's...