benjy_26

Most are, if not, it's not hard to either mod the harness, or drill and tap the head in the proper spot.

When dealing with the pre 96 HO's, look for the 7120 casting number above the #4 exhaust port. This is the "holy grail" head to look for when doing a hi-po rebuild on the 4.0.

Not really. Look at specs for so-called "RV" cams. Typically, they are higher lift than factory cams but shorter duration and less overlap. Their purpose is to increase torque at the low end rather than horsepower at the top end. When I built the first engine for my Javelin race car "back in the day," the cam maker completely misunderstood the performance characteristic I had given him and he gave me ... an RV cam. Gobs and gobs of low end, but where the factory engine would rev to 5500 and stop there due to valve float, the "race" engine was all through at 4500 RPM. Literally ... in top gear that was as fast as it would go, because aerodynamic drag exceeded the available power. Needless to say, I swapped out that cam post-haste. See if you can dig up the specs for the factory Stage 2 cam kit. That would probably be a good target for you. If you might be interested in a factory Stage 3 kit, one of my friends from NAXJA had one. I don't think he has sold it, but he no longer has the 4-banger MJ so he would probably be willing to part with it. If you're interested, send me a PM. Thanks a bunch! :D

Damn... That's a great find!

Thanks for your input! I'll probably stick to 4.56's.

Cool. Where'd you get a Mopar cam?

How fast is your engine spinning at 60-70mph? Your set up seems very similar to what I want, save for the 32's. I'll probably stick to 31's for a while.

Seriously, How much are you going to haul? Meaning are you going to load 2200 lbs in the truck? If you want your cake and eat it also - I would look at a set of air bags or air shocks to increase the payload capacity or to level the truck out with a load. This would be in addition to the springs of your choice. Those two things should work together nicely. Previous owner of my truck added 2 overload leafs on each side and air shocks. All to the full factory Bit Ton/Metric ton package. He used the truck to haul drywall. Me? Biggest load was cement blockes - 2960 lbs worth of them. Just once, and the truck did it! With all the gear and tools I carry when on an outing, I figure I carry about 1000lbs. I also would like to hitch up a 1000-1500lbs trailer to the back of my MJ when going on truly extended outings. I've carried that much (in sand) with my stock springs, but I was hitting the overloads sometimes (felt it on bumps). I honestly hadn't thought of air shocks. How do they handle off road work? Not meg-ultra hardcore rock crawling, but trail rides and maybe some dune blasting (unloaded, of course).

While the 2.5 is loosely based on the L6, it makes all of its power above 3000rpm, torque too. A cam with more lift and duration will give it more of what the engine does naturally, as will the higher compression. While it's not a Japanese DOHC mill, it's still a revver, compared to the 4.0, at least

I just threw in a Powertorque clutch set into my MJ from Oreiley's. It feels close to the same as stock, if a bit grippier and it feels like it has a bit smoother engagement. I like it.

Good info. Thanks! How do they ride, loaded and unloaded?

I'm in the process of throwing in an 8.8 with either 4.56's or 4.88's and am also going to upgrade the braking system. I realize this still won't make it a MT truck, but it should bring me closer. As far as the stock springs having worked for me, they have, but some added capacity would be a welcome thing. I guess I'm just trying to have my cake ans eat it too!

So... if I plan on keeping a stock redline but have a big cam, would new, OEM quality springs be sufficient?

That Siamese boot looks ILL in leather! Must have, if yoj ask me...

How well do you think the 3" leaves would hold up to hauling? Do you think they'll be as durable and capable as the MT packs?

Eagle, if the 4.0 valve springs fit the 2.5 head, would it be safe to assume that the hi-po springs marketed to 4.0 guys would work for us 4 banger guys too?

I'm not going for a bone stock rebuild, but I'm not going über-radical either. I'm planning on an MPFI conversion with a lumpier cam and some overbored, higher comp pistons for good measure. I don't plan on revving it a lot, but this engine will probably make most of its power ar higher rpm's; and I'm fine with that.

What kind of use do you have planned for it? I have been running a set of OME coils in mine along with Rancho shocks for years and I LOVE the way it handles, both on and off road.

Hello all. I'm planning on getting some new leaves for the back of my 87 SporTruck. I use this MJ for light wheeling, camping, and it also does its fair share of towing/hauling. I come to you guys for advice. What do you recommend for my use? Hells Creek makes a Metric Ton leaf set, as well as a 3" lift pack (for us SUA guys). General also makes two flavors of Metric Ton packs. The 4 leaf and the 5 leaf pack. I do have a 3" lift on the front along with 31" BFG AT/KO's and it is a relatively stripped out, 4 banger Jeep with a manual tranny. Thanks in advance!

Reason I ask is because I just picked up a spare 2.5 and am in the planning stages of a rebuild.

Hello all. As I research the Jeep 2.5 mill, I've come across a few bits of info that I find interesting. While going through a forum (I forget which), one user mentioned that the 2.5L that came in our vehicles used valve springs that are relatively weak. This is one thing that I'd like to tinker with. Anyone know of a source for stiffer springs for the 2.5? Do the 4.0 springs fit? Thanks in advance!

Measure the rude height according to the article in the DIY section. Then, you can choose the proper coils to get the look you want. With that said, if your rear is 4 inches higher than the front, grab a set of 3 inch 4WD XJ coils and ypus should be pretty close to even, assuming both front and rear are still within factory spec'd height.

Thanks so much for the update! It peeves me to read a thread that outlines and issue and the OP never comes back to tell us what happened.

I'm curious too.

1989 Eliminator is right. If you havent flushed your system, it would be a good idea. Do you have access to a laser thermometer? I kept chasing overheating issues in one of my vehicles until I zapped the T-stat housing and radiator. Turned out I had a bad gauge.