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Supercharged LS3 crammed into an XJ

I have been out of town quite a bit lately so haven't made much progress but a bunch of parts did come in. Next step will be to cut the output shaft of the transmission so that it will work with my transfer case adapter.
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I also installed some headers, and will need to remove the oil cooler.
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The Header install was easy, just clean the surfaces and put some Ultra Black RTV on there. The header manufacturer insists that Ultra Black left to dry overnight is the way to go, I am a bit skeptical but we will see. You can see the oil cooler that is directly in the path of the exhaust, I hope to remove that tomorrow, I will plug the coolant line at the engine block, and block off the oil ports with a plate that will also allow be to insert my XJ oil pressure sensor.
 
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A photo of the cut down output shaft with the Novak 231J adapter.


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Here you can see that the total length is now 3-3/8"


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I also removed the oil cooler. It was in the way of the exhaust and most people seem to think that it serves no real purpose. The brass plug is GM part Number 12561663. It requires a 17mm hex driver to install.
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Where the oil used to enter the oil cooler I blocked it off and threaded in an oil pressure sensor that I will run into my XJ computer. I am using the XJ computer as a gauge mule.
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A photo from before the shaft was cut. I need to plug those two holes and place an o-ring over the shaft.
 
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That is a nice find and good score! Can't wait to see the final results.




Thanks man. I certainly hit the jackpot with this and I appreciate the interest. I have been working some crazy hours lately and do not have a lot of time to work on this project for the next few months but hope to have it all wrapped up by christmas.
 
You're pretty far along - I guess you've measured? What ECU are you planning to use?


I will use the ECU from the donor camaro. I know the motor will fit cause many people have been down this road, however, that supercharger will almost certainly be too tall for the hood. I also need to cram an extra radiator in there for the intercooler.
 
The main seal is now in. The next step is to plug the other two holes. I tapped them with a 1/4" NPT tap, the wholes are already the correct diameter so it is super easy. Use a vacuum to make sure you get all the little metal shavings out.
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Checking for fitment
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Here they are all plugged up. I put a little Permatex high temp thread sealant on there. I expect these to last the life of the transmission.
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And here finally the Novak 6L80E to NP231J adapter is on. I put a thin layer of Ultra Black RTV on there to keep moisture out. I also put a generous glob of bearing grease on the shaft splines. Finaly the transmission is ready to go back in the car. I also had removed the TCM for reprogramming so that I can bump shift it with my Lokar shifter, but forgot to take any pictures of that.
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My wiring harness is back from Novak. Super clean and convenient. All the wires were labeled and in the correct positions. Whole thing went right back on in less than 30 minutes. Easy peasy.

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I am headed out of town again for quite a while and I dont think I will make any significant progress until November.
 
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Looks like that adapter gives you lots of clocking options.

I will be looking forward to your next installment.
 
I'm guessing you haven't stuck the engine in the XJ yet - I'm wondering how the LS3 pan will fit in there. I'm doing a 5.3 swap now and have a few different pans including an LS3, which I'd prefer to use if possible. I'm also going to try to run the L99 alternator/power steering setup. I think it will clear both the hood and the steering box.



FYI, that isn't a factory blower option on the Camaro. It's a Magnuson TVS2300, an aftermarket kit (a good one). Judging by what I see here I'd bet it's set up for about 6psi. I know you spent some good money to buy this, but you might consider doing a cam swap and get rid of the AFM/DOD stuff. Even just a stock LS3 cam (cheap used) and a few new lifters, valley plate, and a few other misc items would do it.
 
I'm guessing you haven't stuck the engine in the XJ yet - I'm wondering how the LS3 pan will fit in there. I'm doing a 5.3 swap now and have a few different pans including an LS3, which I'd prefer to use if possible. I'm also going to try to run the L99 alternator/power steering setup. I think it will clear both the hood and the steering box.



FYI, that isn't a factory blower option on the Camaro. It's a Magnuson TVS2300, an aftermarket kit (a good one). Judging by what I see here I'd bet it's set up for about 6psi. I know you spent some good money to buy this, but you might consider doing a cam swap and get rid of the AFM/DOD stuff. Even just a stock LS3 cam (cheap used) and a few new lifters, valley plate, and a few other misc items would do it.


-You are right about the blower not being factory, and about the motor not going in the jeep yet. I really wasn't expecting the camaro to have a supercharger when I bought it. It was an auction vehicle and the hood was smashed so no way to see the engine before I bought it. Because of the giant gamble only a couple other people bid on the car and it sold for $5600. Most SS camaros or corvettes with the LS3/L99 were going for closer to $8000 with engines that are known to run and known odometer readings. I really just got lucky with this, could have been a disaster for me! Prying the hood open and seeing a supercharger was a big surprise for sure. It will be fun to flog around an XJ with it but it causes a lot of problems for a swap.
As far as the oil pan goes I am not sure if the camaro pan will work or not, and really wont know until it goes in and I can flex test my suspension to see if it will hit at full compression. At full compression I have somewhere around 2.5" of lift over a factory XJ if that info becomes useful to you.
Because the engine only has 33k miles on it I really don't want to rebuild it to replace the cam or even the AFM/DOD system. I don't put a lot of miles on the jeep, I have had it since '01 and it only has 89k miles on it, so I am hoping that it will last me many years before the inherent problems with AFM/DOD start to manifest.
 
I might know if the LS3 pan works tonight if I get ambitious. The only reason I pointed out the cam is a lot of people have had issues after they start beating on the car after the blower install. I wouldn't call it common, but it happens much more often with a blower and "spirited" driving. It's 8 lifters/pushrods, a used LS3 cam, and a valley cover swap. Could be $200 or less.


I'm also running an E38 (4L60 though), drive by wire, and A/C. You might be interested in an electronic project I started to use the factory gauge cluster and A/C and cruise inputs. It only works on the gen 4 GM stuff (CAN bus), and CCD for the cluster stuff. I don't have the overhead console, but I should be able to get that working, too. You're welcome to a PCB since I'll have to order I think 5.
 
I sat the engine down in there tonight with the LM7 pan and it's clear that the LS3 pan is going to be a lot closer to the axle tube, too close probably unless you have a good bit of lift. I have only the stock worn out suspension in right now, and the LM7 pan does clear everything nicely. The oil filter is close to the pinion yoke on the axle, but should stay out of contact.


FWIW I also have Trailblazer manifolds and the driver's side is just thiiiiis close to fitting. The flange kicks out just a bit too much and it runs into the bracketry that holds the lines there. It might work if the flange is replaced.
 
I sat the engine down in there tonight with the LM7 pan and it's clear that the LS3 pan is going to be a lot closer to the axle tube, too close probably unless you have a good bit of lift. I have only the stock worn out suspension in right now, and the LM7 pan does clear everything nicely. The oil filter is close to the pinion yoke on the axle, but should stay out of contact.


FWIW I also have Trailblazer manifolds and the driver's side is just thiiiiis close to fitting. The flange kicks out just a bit too much and it runs into the bracketry that holds the lines there. It might work if the flange is replaced.

You are likely the first guy ever to LS swap an XJ before modifying the suspension! Talk about a sleeper. I will start looking around for an LM7 oil pan, GM made millions of them so finding one shouldn't be tough. It will also be much much easier to swap that oil pan while the engine is out!
 
I have not had a wheeling machine for 15 years, and in WI the trails went from barely anything to nothing over that span. I bought a stock XJ to build for some mid-level wheeling and to drag behind the motorhome. The suspension stuff won't be here for a couple of weeks, nothing is shipping quickly right now.
 
I have most of the parts that I will need to finish my project, just not any time to do it for another month or so. I dont want to pull the motor out of the jeep until I will have a solid week or so to put the new one in and that wont happen until thanksgiving. In the mean time I will be upgrading my brakes and steering. I think I will make a separate thread for that since I dont see a similar write up on here.
 
Got the new brakes and steering installed. Super happy with that.
Should have my LM7 oil pan and associated parts showing up in a few days. The last parts I need before the old engine comes out and the new one goes in.
 
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