im confused now since the two of you dont agree.. 99 I6 4.0. what do i got?

 

We agree. We're just calling them different things.

I don't call non HO badged motors HO. Especially in your case, since you have the 99+ intake that the HO motors never got.

The ports in the head may be the same size as the HO motors, but since there are no HO badges, and subtle differences, I really don't consider the later motors ''HO'' motors.

 

The start they were called RENIX, then they were called H.O after the first set of upgrades,then late,late 99 they were calle the POWER TECH till the end of their rein.And the only differance in power was a 5H.p raise and a 5 TQ. rise.

 

Power tech? Never heard that before!

 

"Power Tech" is a term that has been used to describe the 4.0 I6 since 1987, through all of its incarnations.

From wikipedia:
source:http://en.wikipedia.org/wiki/Chrysler_PowerTech_engine

From a review written in 1991: source:http://www.cars.com/jeep/cherokee/1991/expert-reviews/

See also:
AllPar's PowerTech page - http://www.allpar.com/mopar/40.html

http://www.yuccaman.com/jeep/history.html#engine

 

So its not just for 99+ years? That makes a bit of sense...

 

x2 the H.O. version had 13 more hp. than the renix hence H.O. PS bye the way fyi the 4.0 was basically a balanced engine with # 1 piston and hardwear for #1 #2 for#2 etc.

 

So...... HO = RENIX ...there basically the same thing then?

 

Different head injection and cam.... not that much better imho. I'm in love with my renix.

 

 

I have a 98xj with the stock motor 220k in it with a few performance mods intake,highflow cat,dual exhaust,throttle body,tune up...etc. And a while back bought a 2000 model parts jeep 114k. From what im understanding the 2000 motor is the powertech which is bout 6 more hp. Was planning on dropping the powertech in my jeep. Will this be a big difference from my 98 4.0 and will the motor mounts be the same?
Thanks.

 

Keep your original block and head. Just use the intake manifold and TB, less work.

 

This has all you need to know right here:
http://jeephorizons.com/tech/xjstockspecs.html

 

Would that be a noticeable power gain? And even with 220k miles on my motor when that one has 114k? I mean I know the i6 is bulletproof lol but I plan on parting the 2000xj out and don't wanna lose the opportunity of a new motor if I'm gonna possibly need it someday

 

I no this thread is old but I'm hoping it will get the same attention. I just bought a 92. The guy said that the engine had been replaced 85000 miles ago and that he wasn't sure that it was the same engine that originally came in the 92's. How can i tell visually between 4.0L, the 4.0L HO and a 4.2L?