rhino1

i got my hands on a 91 two door that i have to rebuild the engine on. if you were doing this, what would you do? cams, intake, exhaust, head work, etc. i dont want to swap anything in, just curious what you all would consider?

rjxj

All depends. Why do you need to rebuild it? How much do you want to spend? Etc.

96Cherokee113

Well, If I were to rebuild my engine, I would stroke it to a 4.6L . You're pretty much just using the internals of a 4.2L I6 from a Wrangler and putting them in your 4.0L. Do a google search and you'll find all the info you need. It's not too expensive and it'll have lots more power.

rjxj

Stroking a motor is a bit more involved then just "swapping" parts.

rhino1

well, i guess i didnt explain much did i. I got the jeep from a friend that junks cars. he picked it up from a guy needing some cash. the motor has been torn apart and its all inside the jeep. guy told my buddy that the oil pump went out and it spun a bearing. its all apart and nothing looks that bad. i have a friend that is a great mech and he looked at it all and said that it didnt look like it spun anything. anyways, anyway you look at it, its got to be rebuilt. i dont mind doing it in steps to have a great motor in the end. but, i am not wanting to dump a lot of cash into it. it will mostly be a drive around toy with some fun mudding in it. i am down around savannah, ga and there are no rocks to play on unless we travel. which i would like to do some in the future. but, mostly just a toy.

rjxj

I think that most of us have a "toy" jeep. I have 2, plus my DD.

If your friend is a mech, then he should know the steps to building a "basket case" motor. The 4.0 has great power, and so on. If you want more, stroke it. If not, just rebuild it, machine what needs to be machined and replace the broken stuff.

rhino1

yeah, he has the rebuild part of it down. I was asking more along the lines off cam, head work etc. the small things that help add up to better performance.

CAEMI

Based on your needs, I would haul the parts to the junkyard and scrap them and buy a used motor on craigslist.

That's my solution to ALL blown engine problems...just buy a motor on craigslist. Rebuilding these 4.0 motors, unless you spend $3500 and do it right and a little more to build a stroker, is a waste of money. These motors are bombproof and will last 200k or 300k even if abused. You can pick up an engine for $500 that will last ten years at your level of useage. And unless you stroke, you'll never make any more power with a rebuild than you have in a used motor - at least not so the butt dyno would notice.

And, if you've ever built a motor from the crank out, you know tha swapping is ten times easier.

96Cherokee113

This is true, but I've built motors before, so I guess I don't see it as being too involved. Also, like you said, most of us have another vehicle. My Jeep is currently off the road until winter hits, so I have plenty of time to build a motor. But if the Jeep needs a motor now, there's nothing wrong with grabbing something from the JY or Craigslist. If anybody wants to read about the stroker choices, here's something useful https://www.cherokeeforum.com/f51/strokers-15710/

rhino1

thanks guys. just day dreaming about things. getting opinions. we dont mind rebuilding what we have, like i said, not sure whats all wrong yet, havent pulled everything out and measured anything. just thinking about things

Cherockee

ultimatly your decision will be based on what your intentions are with the vehicle. Certainly grabbing a JY engine seems like the way to go, but you never know what you're going to get.

if it were me, and I think that is what you're asking, i would go the route of rebuilding, purly for the benifit of knowing my engine- inside and out. the level to which you rebuild will be determined by your budget.

I'm actually building a motor for my 2nd vehicle, so it has to be dependable. Going to have the head cleaned up, new valve seals, probabaly have the block honed and install new rings and bearings. Thought about upgrading the cam but haven't decided yet, too many conflicting opinions. I have an intake from a 99+, and a new header with Borla exhaust. May do a proformance ignition coil and better plugs and might even try this better fuel injector that I hear people on this forum talking about.

I too thought about doing a Storker 4.5 or 4.6, problem is everyone who talks about doing a stroker, has built a stroker, or is driving with one, has a different opinion of what's best. There's too many variables with too many unpredictable outcomes and no one- and I mean NO ONE- will agree on what's the best way to build a stroker. In the end you may spend thousands of dollars, have crappy gas mileage, have to use high octane fuel, and still might not have what you wanted.

Good luck with your build though.

rhino1

thats what i was asking, what would anyone who has been in this position do or what would you have done differently?

Hommersimpson

Check the block.. does it need work? if not drop a crank kit in. have the rod resized , valve job, good gasket set.... and just be done with it...got to spend alot to get much more...

sv41878

I just rebuilt the 4.0 in my 95 and including machine work (block cleaning, bore .030 and hone, polished crank, install new cam bearings and freeze plugs, install rods on new pistons and head refurb) it cost me about $1200. Check enginetech.com out. They no longer sell the kit on ebay where I got mine, but have the best prices around. Their quality, I have put 3000 miles on the motor so far and have no complaints. Whether I will be saying the in 200,000 miles, not sure yet.

It really comes down to budget and desire. My situation was budget controlled. I will upgrade to better injectors, 99+ manifold, better ignition, etc. later and I know the engine, I know it will last awhile and any upgrades will pay off.

If I had $3500 to spend, I probably would have stroked it, but only because that is the only way to get hp gains like I would want if I were dropping that much into it.

Figure out what you have to spend, then figure out what you want and go from there.

xj_maniac_newb

if its only a toy then i would drop a 350 in it....thats what i plan on doin with my beater when i get it