I recently put a turbocharger on my 96 XJ that previously had an m90 supercharger on it. This is the second time turbocharging a 4.0L but the first time on a JTEC ECU. I am using a log style manifold with a standard T3 flange. It's comical but it's actually easier to get to the lower intake manifold bolts with the log manifold with a turbo attached than with the stock exhaust or even after market headers.




The turbo is a Mitsubishi clone s20g/TD06H watercooled CHRA. The oil feed is a tee off the oil sender with the return being a 5/8 hose to -10an barb. The return tap is a steel bulk head welded into the pan. The turbo coolant inlet is fed from the block at the rear pipe fitting on the drivers side of the block. The coolant outlet is returned to the heater core inlet. Other than extending the life of the turbo, the byproduct of this plumbing is two fold. After engine shutdown coolant continues to cycle through the turbo center section and after a short time of easy driving on cool days you have luke warm in cab heat.

The turbocharger is regulated by a 5 psi internal wastegate with a screw type manual boost controller. I thought it would be nice to have a "valet" mode but the power increase is substantial even at 5psi.

The exhaust downpipe from the turbo drops down in the similar fashion to the stock pipe. After it makes the turn behind the transmission bell it graphs to the stock exhaust pipe.

The hot charge pipe follows the oil pan to the intercooler under the front bumper. I am still figuring out a better position for it.


The cold charge pipe then exits the FMIC and snakes behind the alternator up and over the valve cover to the BOV.


From there it is a straight shot into a 62mm TB.

Engine tuning is made possible with an AEM FIC 30-1913. Info about set up can be found here

https://www.cherokeeforum.com/f67/my...em-fic-245405/

Injectors are 36lbs/hr. ev1 4-hole. I am CT emissions compliant with this setup. One seldom mentioned advantage of the FIC is its ability to be disabled. By changing out your injectors to the stock size and installing the bypass harness, full control is given back to the factory ECU. This is very useful for troubleshooting an error with-in the FIC. Just be sure to keep it out of boost or simply unhook the wastegate actuator.

I will add more pics as I go. If anyone has questions about specifics let me know and I will post up as much detail as I can. Thanks for looking.

Just noticed I entered this in the stock section...damn noob. Mods please move.

 

looks good except I would smash that FMIC

 

It's just pipe. With enough you could put it on the roof if you wanted.

 

I agree with Tinytrax. I like everything but the heat exchangers placement. At least it's easy to move it if you ever decide to.

Ever thought of converting to e85 friendly and turning the boost up?

 

I may eventually get a bottom exit intercooler and place it behind the grill. I want to retain AC and so far ive done it without too much trouble. This is what I had on hand so I made it work.

I have had the boost pressure at 10psi. The end goal is 20psi on 93 and meth. Also last time I checked e85 in CT is not readily available. Looking online I can see that many stations come up with it as an option but I have been to them and have never seen a pump for e85. I am willing to see how far I can push the stock internals with minimum modifications and good tuning. MLS HG/head studs/aftermarket rod bolts I consider minimal.

With the right parts at the right price and resources available to the 4.0L enthusiast I think there will be many more turbo Jeeps popping up. This should have been a factory option for these vehicles, everything about it just feels right. Team Viper* for whatever reason didn't venture into a performance 4.0L but they should have.

*whatever PVO was calling themselves in the 90's.

 

Very cool, any issues with the silicone elbows on the cold-side? And are you using v-band clamps?

I dig it, always cool to see a turbo XJ!
I want to build one but right now I can only live vicariously through other's builds

 

The couplers on the cold side as in post intercooler? No they are fine, they are JDM...LQTM. No vbands just tee clamps.

What's keeping you from doing it?

 

Nice!

Do you have a build thread for the M90 XJ?

 

I can put one together, I took plenty of pictures. I would discourage an m90 on a 4.0L though.

 

Wanting to Turbo my daily driver XJ soon. I must retain the AC as it’s too hot where I live in the summer to be without. With that being said would you do the same exact build if you did it again? Which exact Turbo did you use? Did you ever bump it up to more PSI? I’m a newbie to the Turbo world and really just want a little more pep in my stock motor. Been thinking of headers, and a turbo for now

 

Not only would I do it again, I did do it again. This time using a standalone ECU installed parallel to the factory ECU. This lets the transmission operate normally as well as the fuel pump, ASD, cooling fan, idle valve all while having full control over the ignition and fuel.

https://www.cherokeeforum.com/f46/96-srt6-build-254951/

I will upload some videos and post them in the build thread. If you want the same set up that I used I sell almost every part I run. Send any questions you may have to Trevor.skankfootracing@gmail.com