v8 guys mpg braggin rights!!

[projectTK]

i got 17.4mpg in my 89 jeep cherokee, 6inch tomken lift, 87 corvette L98 stock internals, NV4500 TRANS 5SPD OD. warner hub unlocks, 31inch tires. It is worth ripping ur 4.0 out or not to stroker build.

 

[yossarian19]

Whats your axle gearing / how is the acceleration off the line & up hills?
My old man keeps talking about putting an LSx engine in his 72 vette, which means I'd get the L98 with LS1 heads for a song...

 

[projectTK]

currie axles, d60 rear, dana44 front, 355 gears, its peppy enough, 1st gear is a crawler gear, i pull out in 2nd gear, rides 1700rpm at 60mph in 5th about.

 

[Talyn]

You could get better MPG with 4.11 gears. You were running 31" tires with a 6" lift? Was your 17.4 mpg on highway, city or combine?

 

[projectTK]

combined, i dont know about upping the gearing. 410 would put the rpm higher running at 60mph which would suck more gas. Might have more pulling power but overdrive would be pointless. Unless you have proof of another v8 jeep with better mpg then me. I plan on 35's n 488 years down the road.

 

[Talyn]

I was suggesting the gearing on the 4.0L Jeep engine... forgot that it would be different on a V8. Your combined is pretty good though. Do you already have the V8 in your Jeep, or is this for another Jeep?

 

[Johnnie Walker]

Not too bad, With an LSx motor and the right gearing you would be stylin

 

[XJEEPER]

Nice mileage, that what I get in my 2000 with 132K miles, 33" tires and 4:88 gears.

The torque peak on an L98 is close to 3800 rpms, so I would think that spinning the motor in OD at 1700 rpms is a little on the low side. I'd bet that your mileage would get up in the 19-20 range if you geared the rig for a 2200-2400 OD rpm.

http://www.vetteweb.com/tech/vemp_0607_l98_engine_induction_system/photo_11.html

 

[Sherman_thetank]

Damn, and i get 14 in my Chevy 1/2ton :gag:

 

[projectTK]

ur right maybe a little higher would cause less parasitic loss cause of low rpm which would result in better mpg. Thanks i may just gear it up before i put the big claws on. Ill post pics up soon.

 

[projectTK]

Here is my v8 jeep done right!!

1989 Jeep cherokee, originally from cali ( i live in ohio).
6inch tomken lift
warn front hub unlocks
Currie axles d60 rear d44 front 355gears
87 corvette tpi 80000miles roughly
Ron davis alum rad
stage 2 clutchmasters
nv4500trans 5spd
agr steering box
eliminated ac
custom heders
2.5exhaust vxmuffler catco high flow cat
stock interior for now
Everything is beefed up um sure i missed a few things

 

[wolfpackjeeper]

Im diggin it, other than the moonvisors and side mirrors.

This thread is nothing but bad for me. I have started scouring craigslist for F-body part outs. The motor would look right at home in my MJ

 

[xj92]

I've always figured an LS engine would get great mileage in an xj because my uncle gets 18 on the highway in his Tahoe and an XJ is much lighter. Seems like it would be a very expensive swap though because the little things just keep adding up on something like that.

 

[projectTK]

The guy i bought it off of said he had well over 20000grand in it when it was all said an done. This is whats gunna kill you guys. I bought it off ebay for 5100$$ robbed him and left. It was my dream jeep the total package and i plan to keep it for ever and in this shape. I plan on going to silver lake and some orv places that i wont get trail rash from.

 

[FlexdXJ]

My buddy gets 23 on the highway in his WJ! That is a pretty slick motor swap though! :cheers:

 

[wolfpackjeeper]

with a LS1 and T56 my camaro was capable of 18ish city and about 27 hwy. Great mileage. The MJ should get slightly better since it is a tad lighter. HOWEVER, my city mileage was never that good since I really just loved the sound of that motor. Nothing sounds quite an LS motor. You find yourself revving a little just because.

 

[projectTK]

yeppers. at idle it shakes the dash a little n vibrates. Lil rev and it shakes the chasis. I luv it.

 

[projectTK]

another thing i wanna do down the road is edelbrock intake, 52mm tb, and maybe a cam.

 

[Mr_Random]

I'm thinking the mirrors are actually a factory option?

In any case, CLEAN swap! Lovin' the TPI, the L89 is a 5.7/350 with aluminum heads, right?

Our suburban with the L05 gets around 16mpg with the 700r4, how is that? It has a holley 2bbl TBI, with valve body mods on the tranny, but otherwise a fresh (under 50K) crate 350.

 

[xj92]

I had a '99 WJ with a 4.7 for a year also. Got 16-18 on the highway, but only 12 around town. Sure sounded nice with the flowmaster muffler though.