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What 4.0 core should I start with?

Posted: February 14th, 2016, 12:51 pm
by Hussler
I've decided that I want to build the motor for my Jeep without taking the jeep off the road for the duration of the build. It's obd1 and staying that way. I have a junkyard nearby that has just about ever year 4.0 ever made. Which would be the best choice? I understand there is more webbing in the 96+ blocks but are there any other special attributes to look out for?

Has anybody swapped in a wj block? I know they have different engine mounting bolt holes ( I can just make new frame side mounts) But what else? They have the better power steering pump, alternator mounting, intake and belt tensioner. Is the CPS have the same mounting? (that would be a deal killer) does an older dizzy fit right in?

Thanks in advance

Re: What 4.0 core should I start with?

Posted: February 15th, 2016, 3:48 am
by Cheromaniac
Since you have a '92 XJ (like me) it's better to get a block (doesn't matter what year) from a TJ, XJ, or YJ. You'll preferably need a '91-'95 head that has a port on the rear driver's side for the coolant temp. gauge sending unit (a 96-'99 head would be OK but you'd need to relocate the sending unit) so you choices are either:

1. Get a complete '91-'99 TJ, XJ or YJ long block engine.
2. Get a short block of any year from a TJ, XJ, or YJ and get a '91-'99 head separately.

You could get the intake manifold/PS pump mounting bracket/PS pump/tensioner pulley as a complete assembly from a '96-'04 TJ or a '97-'01 XJ.

My stroker has an '00 XJ block and a '92 XJ head with an intake manifold/PS pump mounting bracket/PS pump/tensioner pulley from an '01 XJ.