1991MJPioneer

:popcorn: ummm...well back to the topic lol. Will do!

Thanks and I def will cherish it! If I don't enough already :thumbsup: Never understood...why is it some people are so wierd about the VIN on their vehicle? And for that matter, license plates (being blocked out or blurred in pics)? Its information anyone can get by looking at the vehicle, but cannot easily be duplicated :dunno: Anyway, not to steal your thread...just curious. -James I understand where your're coming from and yes people can see my VIN and tag everyday...but I personally am more cautious on the internet when posting things of that matter.... ;)

I've always wondered how rare it was to find a 1991/1992 MJ...and what drivetrain options were most difficult to find...I would suppose the AX-15 and D44 would top the list....As much as I'd love to build a bad nasty rig out of my MJ...I really don't want to tear up a rare Jeep by lifting it and modifying it excessively....I can't say my MJ is in very good condition...but I'd love to restore it... And no I don't want to give my VIN...but my build date was 9-1990 and it has the skid plate option.... Thanks!

So as I've read...97-01 4X4 AW4/231 should be a no brainer electrical swap...ok The 97 up are ECU controlled...then what the heck is this little box bolted to the firewall above and to the right of the accelerator pedal? It says Aisin AW Co on it....it doesn't matter anyways sice the trans ECU is the same for 4X2 and 4X4 I suppose. One last question...is the body wiring the same for a 2WD 2001 XJ as is a 4WD? I know that there are extra connectors ziptied to the harness on the trans and I'm pretty sure I saw the bulb socket once for the T/C shifer light. Thanks!!!

Well then thats what I'll do when I feel the time is right to do the swap! :yes: Also how is the trans controller different between the two? and will the Neutral start switch and kickdown cable from the 2wd work? Does anyone know what year XJ I should get the trans and T/C assembly from? or rather what years are compatible electronically with a 2001? Yes I will!!! :thumbsup:

Well I'm sure this has been covered already somwhere... My main question is...can a 2WD AW-4 be adapted to fit a 231? or will I need to just get a 4WD auto? the Jeep is in awesome shape....only 100K and is worth making into something in my opinion...Is this swap worth my effort or should I should I just try trading it or selling it on craigslist for a 4WD XJ of comparable value? Thanks!

I'm putting a 98 4.0 block into a 91 MJ.....as for the computer issues, I agree. Some of the sensors in the intake manifold will swap...IAT/TPS sensor for example. Although these engines have different power steering mounting patterns on the intakes. You will need to use the 98 intake manifold to retain all the sensors, fuel injectors, fuel rail and throttle body, as they are different from a 91. Just swap all sensors from the 98 engine to the 91....it should be pretty staight forward. Also the fuel pressure for a 91 H.O. is 39 PSI I believe and for a 98 it will be 49 PSI. 91 fuel injectors are supposedly rated at 21lbs/hr. A 1998 is rated at 23.3lb/s an hour...they have grey terminals on the injector. Hope this helps!

Well I'm in no hurry to get the engine done so I should do it at least semi-right with a cam. Yeah I hardly ever get near 4,000 RPM with a 4.0. I have an 01 XJ with 3.55's and an auto and if I punch it at 65 on the highway..then maybe it'll get close to 4,000...but I don't do that often. So, I will just keep the stock springs and go with a good cam. It kinda sucks that I already have everything together...but I'd like to have a decent running engine...so its worh it. Thanks for the links!

Thanks for the info...unfortunately I already have the short block assembled with the stock cam in it... :wall:...oh well I'll just take it out I suppose. Any ideas on what cam I should run? I know comp cams makes a .476/.484 lift cam thats popular. I have a rebuilt 4.0 head...7120 casting sitting in my garage...it has stock springs...how bad will my valve float be with a cam? I'm on a pretty tight budget. Can I still use stock springs at all?

So I'm new here and thought I'd post somthing to get myself started. I've been building a 4.5L stroker for my MJ for the past few months in my spare time. I'm running stock pistons and stock cam from a 98 4.0, 7120 head, 4cwt crank and 707 rods, and pretty much stock everything else. According to JeepStrokers.com its a bad idea to use stock pistons and cam with a stroker because I'll end up with 9.7 to 1 compression and bad quench and so on.. My plan is to run the coolest spark plugs possible (champion RC9YC) plugs and to get a bigger radiator to reduce the chance of detonation... Anyone have any input on what might happen with this motor and what I'm gonna have to do to keep detonation under control other than premium fuel? :dunno: