Interesting thought.
Jeep 4.0 ho and 2wd trans as a drivetrain for doing autocross, hpde, hillclimbs, etc.
Common as dirt, cheap. 190hp/230tq according to Google.
What are y'all thoughts and experiences? Seems like if it was a good idea, more folks would do it. Google didn't tyrn up a lot of quick results....
I'm a fan of these engines, but it looks like there's a better option for a straight six.
I seem to recall a 2wd XJ getting campaigned in LeMons a while back. I'd search their forum and see what pops up.
Didn't the Archer brothers run Jeep Comanche pickups in some series back in the 90s?
Thought It wasn't a fever dream. Googles say 88 tho
Team Petty Cash Racing was the Lemons team.
06HHR (Forum Supporter) said:Didn't the Archer brothers run Jeep Comanche pickups in some series back in the 90s?
Thought It wasn't a fever dream. Googles say 88 tho
If I recall correctly (and it's quite possible that I do not), those might have been four cylinders.
Woody (Forum Supportum) said:06HHR (Forum Supporter) said:Didn't the Archer brothers run Jeep Comanche pickups in some series back in the 90s?
Thought It wasn't a fever dream. Googles say 88 tho
If I recall correctly (and it's quite possible that I do not), those might have been four cylinders.
Yes they were. They Commanche was pretty competitive, what with not needing to worry about a camber curve with the front suspension.
I owned one of the 2.46L Commanches, and I can assure you, Race Car was not a thing I thought very often when driving it.
The 2WD Cherokee has/had a spec class kind of thing in desert racing.
I'm always pleasantly surprised how quick my XJ is. 3000lbs with 190hp ain't too shabby. For endurance racing I like that it's a lower revving engine. Also, they'll bolt up anywhere that an AMC 6 once resided, like an old gremmi, javelin or rambler.
Quick research shows they drop off a lot after 4500 rpm. If you want a straight six go with something that'll scream.
Quick googling suggests those engines are at least 50% heavier than a BMW S52 and make less torque and a lot less power from 25% more displacement. And S52s aren't exactly exotic engines, especially by today's standards. I don't see any upside.
They are cheap, but so are LS engines.
In reply to John Welsh :
The Jeep XJ-R! One of my favorite Challenge cars of all time!
In reply to John Welsh :
That Jeep, and that BangShift article, was my introduction to GRM. Been wanting to build something ignorant for Challenge ever since; finally getting it done
buzzboy said:I'm always pleasantly surprised how quick my XJ is. 3000lbs with 190hp ain't too shabby. For endurance racing I like that it's a lower revving engine. Also, they'll bolt up anywhere that an AMC 6 once resided, like an old gremmi, javelin or rambler.
I've thought about the idea of putting one in a mid-1960s Rambler American. They only weighed about 2500 pounds, so there'd be a decent performance gain.
John Welsh said:
I went to my first Challenge just to see this Jeep. Watching it kick ass on the autocross course was hilarious, Jeeps shouldn't be that quick.
They are great at being jeep engines but they dont like high revs and they HATE getting hot. Head gaskets blow pretty quick on an overheat.
Guys make pretty solid power by stroking it with a 258 crank, but it would be difficult to justify doing all that when, as stated above, a guy could just throw in an LS pickup truck engine in it.
Well, I can certainly think of lighter ways to get 6 cylinders. They weigh in at 500 or so, which isn't bloated, but not really a good trade-off for the power they make.
Sure are bulletproof though.
Edelbrock now makes an aluminum head for them, which I'm sure carves off a huge chunk of weight
We made a 4.7l stroker in my shop for a YJ Wrangler. It was very impressive. It would idle up my sloped entrance to The Toilet no problems while my 4.0 XJ with the same gearing needed gas.
Jeep 258 crank and rods with a 0.040 overbore.
My friend that did it said he'd have gone TBI 350 if he had to do it again.
I am a big sub 8cyl guy (unless you want to talk about v10s lol)
In reply to DeadSkunk (Warren) :
I was there for the XJ-R years too. It's one of my all time favorites mostly because it amazing to watch it do things it was never really intended to do.
Now I go back to see Warren too. 
Sadly, not going this year.
The jeep 4.0 is easily one of the most reliable, takes a beating and asks for more engines i have ever owned. +1 for racing.
Also, they are terribly inefficient at making any real power. NA, it is hard to squeeze much more than 300 or so out of them. Some have tried, but they just don't have it. Its a tractor engine more or less. Off road, sure. the old L6 makes decent enough torque and as mentioned above, will take punishment like few i have ever seen. but not for a higher RPM racing application. They beg to be beat. the only 4.0's i have seen fail have been the ones in a typical daily, treated nice, regular maintenance. treat it like a $3 hooker and they last forever.
Pretty sure that this engine, for my purposes, doesn't have enough benefits to justify it.
Thanks!
Im exploring other options than ls. But i keep coming back to ls as the easy button.....
Different bellhousing, but a 2JZ is similar in size/weight and bolts to several of the same transmissions as the Jeep motor, with potential to make wayyyyyyyyy more power.
Whats the vehicle in question you need propulsion for? Whats your power target?
You'll need to log in to post.
