4.0 L high output?
- Thread starter Tomdakota
- Start date
Yes I think this was pertaining to the YJ era when Chrysler took over and got rid of the carbureted 4.2 and turned it into the fuel injected 4.0.
I’ve seen it passed around that the YJ 4.0 made a little more power than the TJ, but I’ve never actually researched the claims.
I’ve seen it passed around that the YJ 4.0 made a little more power than the TJ, but I’ve never actually researched the claims.
The Wikipedia article on the 4.0 engine talks about various horsepower outputs, and in 1991 they made several changes to the engine resulting in the final 190 HP and 225 ft. lb. Chrysler called it the "4.0 Litre HIGH OUTPUT" engine. So all of the TJs could claim HO. Not that it means anything in the real world.
At least you’re not looking for one of these!
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This is the correct answer. All TJ's would have had the 4.0 H.O. installed from the factory. I had an '88 XJ cherokee with the supposedly 177hp and 224 ft. lb. Felt moe like 130 hp and 180 ft. lb. even with the 456's in both pumpkins. My cherokee was an oddball with a Peugeot 5 speed manual tranny and a non-C clip dana 35.
Yep I owned one of the earlier 4.0L engines in my 1990 Cherokee XJ which had 177hp, up from the original 173hp when the 4.0L first came out in 1987. When Chrysler purchased AMC/Jeep they updated the old Renix engine management system, tweaked the intake and a few other things to get 190hp in 1991, which is where the "high output" came from on 1991-1996 XJs and on 1991-1995 YJ Wranglers with the 4.0. Once the TJ came out, they dropped the "high output" marketing.
Yes, it doesn't do much good to call it High Output when there is nothing to compare it to except the "Low Output" 4-banger, and they wouldn't want to say that. But I do love the photo from Jamison C above.
I have enjoyed the chrome bragging on the sides of cars for decades, showing whatever the current great thing about the car was. Engine size, V8, fuel injection, turbo, tranny type. Some are kind of funny, like old VW bugs with their Automatic Stickshift.
This is HO:
This is LO:
TJ engines fall in between, so perhaps they're MO.
(Mediocre Output)
JKP
TJ Addict
If you ever drive a carb'd 258 or 4.0, you'll understand why it was HO at the time.
Also, it was making as much or more HP than Ford and Chevy's 5.0 V8s at the time.
Also, it was making as much or more HP than Ford and Chevy's 5.0 V8s at the time.
I had a '74 CJ5 with a carb'd 258 (4.2L). It was powerful enough for the light CJ5, but it had all of the attendant problems of a carb, particularly the lousy design which let it dump raw gas down the barrel when climbing at a steep angle. Compared to that, the TJ 4.0L is HO, and dependable.
I also had a '68 Camaro with a 327 (5.4L) with 225 HP. The TJ 4.0L isn't very far behind that. But a few years later they started rating engines as net HP, which would have dropped that same 225 HP to something like 150 HP.