1991Jeep_Man

I need some input. I will be doing a v8 swap into my XJ hopefully soon, but I am in a snag.

I know FrankZ did his LM7 5.3L swap, and I have read his thread over and over again. At first, I was set on a 5.3L, however after recent local searching and pricing, appariently the only LM7's and such around here were either abducted by aliens or built from pure gold components with pure diamond injection.

Another route I considered was a 1996 Chevy LT1 5.7L. Appariently the market for this engine is good, and the optispark issue can be easily maintained and prevented or even eliminated.

Which direction would you all go?

And before anyone chimes in about it, a stroker is not in question. I wish not to spend $5k+ to build a hopeful stroker that will actually last. The experiences of other members has led me from building a stroker.

Thanks for any input!

N20jeep

the LT1 is a decent motor, but with any motor swap you will have unexpected cost.

what transmission were you planning to use? what tcase or were you going to run an adaptor?

just make sure to figure thing like this into your swap cost
-adaptors
-mounts
-accesories for engine
-bigger radiator
-custom length driveshafts
-hoses
-electric fans
-exhaust work
-random nuts, bolts, clamps, fluids
-plus more

all this kinds of stuff can easily nickle and dime a job into not be affordable to finish.

N20jeep

also, a stroker can be built for MUCH less than 5k

1991Jeep_Man

Yes, but I have heard from MANY instances, from members on the forum to other local XJ owners, that the cheaper it's built, the less it will perform.

As for the v8, I have a source (novak-adapt) for mounts and what not. I would swap out the input shaft on my current NP231J to the NP231C 27 spline input, much like with either the LM7 or LT1 engines 4l60e tranny. However, IIRC the LT1's earlier 4L60E transmission has a different bolt pattern, but novak has the adapter plate, or I can probably machine one myself. I am basically prepared for all aspects of either engine swap minus the decision for which engine to go with. And still should one come availible with reasonable pricing, I will probably still buy an LM7. But, if they continue to have diamond encrusted pistons, then the more availible LT1 will be my choice.

biztyke

and what is this based on? is this getting someone else to build it for you?

last time i priced it(as i plan on one in the near future) it came in under $2k. this includes all parts, all machine shop work and a used 4.0 motor.....all labour would be done by myself. assuming i use a decent machine shop and really do my homework before i build i don't see what could make it a bad motor. certainly a hell of a lot easier and cheaper than doing a v8 swap.

but regardless, if you have the time and money i commend you for taking this on. if i had the space and time i would love to try something like this just to have fun with it, perhaps later on in life when i own bigger property. i can't give you any advice, other than i have read a few v8 swap threads and a number of people having some trouble with the novak mounts......don't know the detailed tho.

00SportXJ

+1 for the 5.3. Any modern GM powertrain is hard to beat. I feel your pains with the cost on them though. I've been trying to find one to replace my 4.0 with. From what I've seen, you can save a few hundred and "settle" on the 4.8. You might want to keep an eye out for a LM4 too. It's an all aluminum version of the 5.3 used in the Trailblazer and Envoy.

On another path, a buddy of mine put a Trailblazer Atlas drivetrain in a CJ. It was pretty impressive. A XJ would do pretty good too considering it weighs half a ton less than a Trailblazer. They can be cheaper than a 5.3... food for thought.