Questions and Pictures.

throttle body injection, If you change the head you have the option of TBI or Tuned Port Injection. Have you considered which?:cool:
 
throttle body injection, If you change the head you have the option of TBI or Tuned Port Injection. Have you considered which?:cool:

If it were me I'd get the TPI to go with it from the doner.
 
I don't see any real advantage to TPI. Fuel delivery is not sugnificantly better, if at all and you need a crank sensor which would be a major expense or at least a PITA. I am leaning toward the mega squirt system, junk yard parts, uses tachometer signal and is programable by me. As an added pluss, if I am totaly out of my mind I can even assemble the controler myself. Whats not to like??:cool:
 
i think you need to do the tfi upgrade first. you can put the 4.0 head on a wore out motor but you may not see much of a difference, being as your compression probably is below stock numbers because you have alot of miles on the motor, there is no physical reason it will not work though. you also don't have to put fuel injection on at the same time as the head swap you can use your factory 2bbl intake, and add the fuel inj. later. i should have done the head swap when i rebuilt mine instead of wasting money having my stock head reworked, oh well. as for tune port injection there is only one setup i know of and its for a chevy v8 mostly used in camaros, you would have to use the intake manifold for that, which will not work on a I6. the junk yard TBI also comes off of v8 or v6 chevys, but you don't need the intake from it just the throttle body, wiring harness, engine computer, adapter for the throttle body to intake, and various other little goodies.

as for the suspension i think i would get rid of the lift shackles and get some lift springs although those may already be lift springs idk. if you want to keep the same height or go higher i would look into a SOA setup but do your research and do it properly. or if you want to keep it like it is and correct the caster problem you could cut off the leaf spring perches and weld new ones on and set the pinion anlge yourself, which would put the caster back at the right setting.
 
If it were me I'd get the TPI to go with it from the doner.

cheepjeep is right about the tpi. what I really ment is the MPI system that came on the 4.0
 
yeah the mpi is a good swap i hear. but in all honesty if i was going to rebuild the motor, do a head swap, do the factory mpi swap, which you will need to rig a crank position sensor for. it might be more economical to just swap in a whole 4.0 liter if you can find a good low mileage donor vehicle, in which case you could get an ax15 5-speed which would be a real good thing if you have a T-4 currently
 
yeah the mpi is a good swap i hear. but in all honesty if i was going to rebuild the motor, do a head swap, do the factory mpi swap, which you will need to rig a crank position sensor for. it might be more economical to just swap in a whole 4.0 liter if you can find a good low mileage donor vehicle, in which case you could get an ax15 5-speed which would be a real good thing if you have a T-4 currently

Ya but then you end up with the short stroke motor and what do all CJ owners want to do? Upgrade! Now you are looking at stroking the 4.0 motor to get the torque back you lost.
 
nah i've driven a few jeeps with 4.0 liters and they do fine, i'd just drop one in and go with it and in all reality if his motor has as many miles on it as it shows on the od then how much torque is he really making now? a stock 4.0 would be a big improvement over a wore out AMC 258 i6 / 4.2l right?
 
Ya, your right. My wife used to have a 95 Cherokee with the 4.0 HO and that thing really ran good!
 
my uncle has a 92 yj it had AMC 232 i6 ,000 hard miles on it when we replaced the motor, it smoked like a freight train but still ran strong, needless to say i was impressed with it. we replaced it with a crate motor a guy had bought for his jeep but got cancer and needed the money, he got a crate motor for $750. and i got the head off his old motor
 
From what I've been reading on Novak-Adapt.com the Transmission I currently have would be better than the AX15. Plus, it would give me a chance to learn how to rebuild a Transmission . The suspension is something I'm going to have to take care of. I'll be digging around over the next few months figuring out what I need to do with the suspension while I look for a new engine. I'll probably search some junkyards for a TJ and yank the engine and axles. For the time being though I'm just going to replace the engine mounts so I can keep wheeling.

Oh, on a side note, I need a good roll cage. I found this one here that looks promising, but does anyone here know of any others?
 

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