TJ Roll Cage and LS1 Swap

[UNSTUCK]

With the cage about done, it was time to pull it. Doing so required removal of the dash, which wasn't bad. We played around with the door bars and decided that removing them with the seats installed was going to become too much of a pain. I removed the tube clamps and made the door bar with a support permanent. I will have to notch the plastic door trim a bit to make the doors close when Braden runs them. It should look okay with the door closed, as the trim will wrap around the tube. I then installed the lower windshield bar and the V bars. After that was the mirror brackets. Braden picked up a 180* race style mirror that he is pretty excited about. With that stuff in place he came and picked the cage up to get powder coated.









While the cage was getting coated, I tore into the heater box to replace the core. I have never replaced one on a TJ before and the research I did lead me to believe that aftermarket units are just about junk. Well the dealer wants $450 for one and this one from Autozone was like $75. I found the fit was pretty good, although it doesn't have the amount of rows that the oem unit had, so we'll have to wait and see how hot the air will blow.




After the heater core was finished I went to work on firewall bars. I drilled the holes for the bars and figured out how I wanted them. Now I just needed the cage back.


The cage back from coating. I think it turned out really well. Maybe just a bit too much shine though. Doesn't match the other black on the jeep. I like flat anyways.

 

[blznnp]

Looks good

 

[UNSTUCK]

With the cage installed again, I was able to finish welding the frame tie-ins on the frame. I had them built before and send them to the powder coater, then just welded them to the frame. I needed to remove the tank to weld in the rear tie-ins, also so I could install the Novak fuel regulator. Once the cage was finished I was able to add the firewall tubes. They tied into the shock hoops. Braden is planning for bypass shocks this winter. This will require a new hoop, and redoing these bars. I left enough stick out before the bend that they will be easy to sleeve and build off of next time.













So just when I thought I was finished with tube work on this project, Braden decided to build new tube fenders. Those will be built after then engine is in and running. At least I can put the bender away for a bit. Anyways, the dash is back in and I'm ready to start on the motor. It really is kind of a boost to have one long project done. I have used 7 1/2 tubes on this project so far, the most I have used on a cage before. I think it turned out really well. I feel like the mountain climber that just summited McKinley. It's also a huge boost when a customer is smiling and says they love it.

 

[UNSTUCK]

Started in on the harness. I have gutted just about every fuse and relay from the PDC and most of the wires from the stock PCM. Really the only thing the stock computer does now is run the stock gauges. If we had went with aftermarket gauges, we could have done away with it as well. So Novak came up with an emulator box that takes the tach signal from the new GM PCM and turns it into a signal that the jeep PCM will recognize. the emulator then sends that signal to the jeep PCM through the crank and cam sensor wires in the stock jeep harness. This tricks the jeep PCM into thinking it is running the stock engine. Then the jeep PCM can send a signal to the tachometer in the gauge cluster with the right engine speed. All of this is in theory of course. The main question I have, and maybe someone here can answer it, is what keeps the jeep PCM from throwing on the MIL? Since it is not getting the right signals back from the rest of the sensors, such as O2. The Novak instructions seem to have left that part out. I will be installing a new MIL that goes with the GM PCM, I wonder if I will have to get in the gauges and remove the stock MIL?

Anyways, just a few random pictures. This first one shows the start of the harness tear down. Braden has a TON of auxiliary power items. Before, they were just kind of thrown in there. Now they will all be part of the main trunk line. I hope to have whats left of the stock harness and the new gm harness seamlessly integrated into one unit. I almost love wiring. I would much rather wire up an engine bay then build a roll cage. I pretty much have OCD when it comes to wiring. I have a feeling I might have to redo the Novak harness to make it work.



This bracket, mounted right under the master cylinder, will hold the GM PCM, Novaks Fuse box, and a few other loose relays. As well as the Novak emulator box.


Maybe someone from Novak can explain how to mount their fuse box?


Every wire connection will be soldiered and wrapped with heat shrink. This isn't as big of a deal on wires carrying 12-14 volts, but on sensor wires where half a volt can make a difference on how the engine runs, you need to be sure to have no voltage drop from a bad connection.


I'm off to PHX in the morning for a week of fantastic OSHA training. This sets me back a week, and I'm already WAY behind on this project. Mostly I just hope to be able to remember which wire goes where, and am secretly hoping little trolls will come over and finish this thing for me.

As always, more to come.

 

[RockChucker]

I mounted my Novak fuse blocks on the grill support rod that runs from the firewall to the grill. I am running highline tube fenders and there is not the real estate to mount them anywhere else. it works ok. In terms of the MIL. I took my gauge cluster out, popped out the stock bulb and scratched off all the conductive material on the PCB of the cluster. Then I took Novak's MIL bulb and cut it right out of the harness. I believe I soldered the factory Jeep MIL bulb onto Novak's wiring and put it back in the hole it came out of. When my check engine light comes on it shows up like the factory Jeep. Way cleaner than having a red LED mounted somewhere on the dash...

edit: Looks like you are a little better off than I was for space since his Jeep is not a standard trans. The clutch master eats up a lot of space...

 

[Bart]

Nice work.

 

[UNSTUCK]

The fuse box mounting was more of me just venting off some steam. I had Carl cut and bend me a bracket. If anyone was to buy this box from Bussmann, you would get a mounting bracket that sits the box up a bit to allow room for the wiring to come out the bottom. Strangely enough, Novak does not get this bracket when they order them, and even more strange, I'm the only one that has ever called them to ask about how to mount the box. For some reason they feel people should be on their own for the little details of this install, even though more then $3k was spent buying their parts. The little details are ALWAYS the most important.

On a brighter note, the weather here in Phoenix is great. No snow!

I love the MIL light idea. I may have to copy that idea. Thanks a lot.

 

[UFAB]

When ready for a dyno tune. We got you covered. So far 80% of all mail order tunes have been failures. We have used 3 different vendors stateside.



Sent from my SPH-L720 using Tapatalk 2

 

[UNSTUCK]

I didn't know you did dyno tuning. I have a guy that I use for that when needed, closer to me. Thanks though.

 

[UFAB]

Ya. We got a dyno. Not.. well yet

Just making biz contacts with reliable intel.

Tuning is so overlooked. Just lately we realized how important a good tune means.

Thought I saw that cage at cornaby powder coat.
Looked good

 

[UNSTUCK]

That's possible. I'm not sure who Braden used, but I know they are in your neck of the woods.

 

[UNSTUCK]

Time for an update. It's been a while. I had to go to PHX for a week for some work training, which really hurt me for Jeep Time. But at least I was able to get some sun. My brother that lives there is buddies with Gonzo. He was able to get us some front row seats to a game. I highly recommend sitting up front for a game. It's awesome! I even got a ball!!!





Then it was off to the Phoenician Golf Course. I love that course. I did a bit of work while I was down there as well.



Once I got back I was about ready to set the engine. The wiring was cleaned out as much as I wanted it at the moment. So I pulled out the Novak motor mounts from the box and realized that they didn't weld one of them up. So I quickly welded it to match.



Novak's instructions tell you exactly where to tack the mounts in place. 4 1/4 inches back from this hole in the frame, if you can see it in the picture. So with the mounts tacked in place, I was just about ready. Novak tells you to install the drivetrain as one unit, so I worked on putting the three parts together.



I needed to make provisions for the stock jeep temperature and oil pressure senders in the engine. On the passenger head at the rear, there is a plug in the water galley there. It needs to be drilled out to 3/8 pipe. Load your drill bit up with grease to catch all the metal shavings and go slow. Clean off the bit a few times as you go in and reapply more grease.



It's the same process with the tap.



The sender installed and ready to go. If you are not going to reuse the stock jeep gauges, then you can get an adapter from Auto Meter that will allow you to not drill/tap and convert the metric threads to 1/8 pipe for their senders.



This is a good spot for oil pressure. The port is already drilled, and ready to be tapped for pipe thread. All you need to do is punch through the very bottom as seen here. Use a smaller bit then the hole itself.

 

[UNSTUCK]

Tapping and installing the oil pressure sender is pretty straight forward.

View attachment 90786

View attachment 90787

So then I was ready to install the drive train.



Slides right in......until it stops.



There is no way to get past the motor mounts. You will have to install the engine by itself and then lift the tranny and t-case in from under the jeep... But before you do that.... I removed the passenger side mount and slipped the assembly in place. Novak puts a few mounting holes on the engine side mounting plate so you can fine tune the forward/backward location of the engine. They tell you to start with the engine all the way back and move it forward if you still have room behind the radiator. So with the engine all the way back and the pass side mount tacked back in place, I found I was still about and inch or so from being able to set the engine. This was with the back of the heads up against the fire wall. Novak tells you a little fire wall trimming is needed. That didn't help any. So I moved the mounts to the far forward hole location. Still no go. That's when I noticed that even if I could get the motor back further, they were too wide to line the holes up. I was stuck (pun intended )
I ended up cutting off both frame side mounts and moving them to the front about 3/4 of an inch. As they come forward the frame also comes in making the gap narrower. I found this to be a good spot. I moved everything to the pass side as far as it would go and found the gap between the frame and the driver side frame mount to be about a 1/4 inch. The frame was still to wide. I slid the engine over just enough to get a good weld on the driver side with a gap. I didn't dare come any further forward for fear of the pullies getting in to the radiator.



Ta da!!!! It works! After throwing Novaks instructions out the window and just figuring it out. Should have done that a long time ago! I can't pull the whole assembly out which is pretty lame, but for now, it's in place, and looks half decent.




So from there, we have made more progress, with less pictures. I'm kind of in scramble mode now. Who needs sleep?

I finished the major wiring, including reworking some of the Novak harness and cleaning up a lot of older, added on wiring. I hope to have it all looking better then stock when I finally put on loom. I got a bunch of fuel line parts and fittings without realizing the stock fuel line was metric, and metric fitting are hard to come by. So I replaced the stock hard line with a 3/8 SS line, then used some Russell hose and fitting to bring it up to the engine. Looks nice. After that I run tranny cooler lines up to a cooler that has been mounted, but sitting idle for a few years just waiting for this swap to happen. Then installed the Novak radiator/fan assembly. It's a real nice unit and recommend it, based on it's looks. We'll see if it will keep the engine cool. Novak didn't have part numbers on this new design radiator, but I got them to give me the numbers they used on their old radiator. These hoses still worked, just needed a bit of trimming.

So with all the fluids put in, this thing was ready to fire!

A quick test of the key switch showed the newly installed MIL was turning on for a second then turning off again, and staying off. NOT good. The light should stay on while in the run position with the engine off. Then we noticed the dreaded Jeep SKIM light on.
Novak wants you to use the stock Jeep fuel pump relay to power the GM PCM. So the stock ECM was turning on with the key, then going into SKIM shutdown and turning off the fuel relay, which was turning off the GM PCM. I temporarily grounded the fuel pump relay, and with the key on, it left the MIL light on! We could hear the fuel pump kick in. We cycled the key a few times to prime the fuel rail, then cranked it. Fired right up!

But no gauges on the dash. Because we couldn't verify oil pressure we shut it right down.

So this is where I'm at now. I need to figure out why the SKIM shutdown is happening. The owner said it has happened once before, but quickly reset and was okay. Research is telling me I can swap the ECU out with a 1997 ECU which doesn't have the SKIM function. Fingers crossed, we should be good. If you have any thoughts on this, I'd love to hear them. The whole reason for going with all the Novak parts was so that we could reuse the stock gauges. Now they are dead because of the SKIM. Has anyone had this problem and worked around it? What did you do? As a side note, the ODO says, "No Bus" while this is happening. I wonder if I cut a wire that I wasn't supposed to. Novak lists all the wires that need to stay and I double checked that all those are still in place, except the A/C wires, which this Jeep never had. I doubt that system is ran through the A/C wires.

 

[RockChucker]

Integrating the Novak harness to make everything work right (read: emissions) was a pain and I ended up having a shop do all the emissions integration. But my harness was wrong from Novak. Mine was a little different in the fact I'm running a manual trans behind a 5.3 that never had that option in any vehicle. My tune is based off a 4.8 but has 5.3 fuel mapping and what not. Note to self, never do a mail order tune again. Lots of wasted time and money.

In terms of getting the gauges to work, I have a 97, so apparently the skim was never an issue for me to begin with. Kind of a bummer.

Also, I ended up using novaks instructions as a reference and basically figured it all out. Their wiring instructions were a joke. The only good ones were the trans adapter and where the motor mounts go. I was able to put my mounts where they described and the motor is all the way back. I trimmed some on the firewall and massaged it quite a bit with a rather large hammer. I do have a body lift too. Maybe that helped? I also put the motor and trans in together. I pulled everything out and it was the biggest pain. But having the trans only wasn't bad.

It might be worth it to call and talk to Dave up at Novak with your skim issue. If anyone up there has a solution it would be him. Good luck.

 

[UNSTUCK]

I should have just thrown all the instructions out the window and figured it out. Every other ls swap I've done came with no instructions so figuring it out was the game plan. But trying to do an install like this the way someone else did it, in this case, as you said, was a joke!
We deleted all the emissions on this one, so that was one less headache. The problem with calling Novak is that they only want you to talk to your salesman who is also your tech support. Funny how every time I call with a tech question, by salesman passes me on to another. I did get good help over the phone this morning so we will see what happens when I get back at it tonight.
I may not sleep tonight. It needs to be on the trailer Wednesday night.

 

[UNSTUCK]

Oh, speaking of harnesses, can anyone tell me if the oil pressure sensor on the back of the block on these ls motors is for the gauge only, or does it send a signal for the computer as well? This is the only harness I have received from a company that "thinned" that circuit out as well. Seems to me that the computer would want to know what the oil pressure is. Any thoughts?

 

[RockChucker]

That's why I referred you to Dave up at Novak. I've talked to a few different guys but I always go back to Dave. He's the only one that has told me what's what with out trying to sell me something I didn't need.

I believe the oil pressure sensor feeds the PCM which then, in a gm vehicle, feeds the gauges.

 

[Bart]

Bummer about the SKIM and the gauges. When I was building my stretched TJ I accidently hooked up the SKIM wire. Once activated I don't think you can turn it off. It was a pain but I ended up going out to Doug Smith and had a couple of keys made to match the SKIM. Probably not the solution you're looking for.

 

[UNSTUCK]

I picked up a junk yard Jeep ECU yesterday that had a black key in the ignition. Took it home, unplugged the SKIM unit, disconnected the battery, waited a while, unplugged the stock ecu, plugged in the newish ecu, battery, then started it. No luck with the gauges and still the "no bus" message in the digital display.

Did a ton of research, found out that the "no bus" can pop up with a bad TPS, bad CPS, disconnected Bus wires to any of the modules, ect. Well, per Novak, I got rid of the TPS. The new Tach module from Novak is (supposed to be) sending a crank and cam signal to the stock ecu. I ohmed the two bus wires from the SKIM to the ecu. They have a perfect connection. I checked all the harness plugs under the dash that I removed when I pulled the dash out for the heater core swap. They are all good.

I put a mechanical oil pressure gauge in it last night to verify oil pressure. It had good pressure! I was finally able to let it warm up, and then hit the throttle a few times.

It sounds gooooooooooood!

So on to the next issue: the electric fan.

We got the engine good and hot, about 220 with the fan never coming on. Novak installed a fan relay that operates on the ground side of the circuit. There is 12v on the switch side, and then, I assume the GM ecu closes the ground on the other side of the switch when it hits 210*. The problem is that I have 5 volts on that wire I think should be ecu switched ground. If it is an ecu switched ground wire, it should never have voltage....I think. It's either an open circuit or closed to ground. Having 12 volts on one side of the switch and 5 volts on the other side of the switch will never allow that relay to close and the fan come on.

I just left a message at Novak......

 

[UNSTUCK]

Well time for an update.

Got the fan figured out. After talking to Novak about it, they just told me that I didn't know how to use a meter and that I needed to test it again, being sure to put the right lead in the right spot. They also told me that there was no way that ground wire would ever have voltage. So I went and bought a "DVOM for Dummies" book and went back to work. Turns out I'm not a Dummy.



So the fan grounding pin is 42 in this picture. The blue wire at pin 46 is the ground wire to my fan relay. Pin 46 is the reference signal to the GM fuel tank pressure sensor. It is supposed to put out 5 volts. And to think, I spent all this time relearning how to use a meter.

After I repined the wire, the fan worked as it should. I'm not sure I liked that the fan was set to come on at 210*. That seems way high for a rock crawler. Anyone have any thoughts on that?

So with the fan working the next project was installing the Winters shifter. Novak makes a nice machined adapter that lets you bolt the gate shifter to the the stock center console. Once again, there are no instructions so you are kind of left on your own.

The tabs hanging down fit under the plastic of the console and then you tighten up the counter bolts to pinch it, and that holds the adapter in place. There are four tabs, but just two in this picture.


With the adapter in place.


Notice this mounting spot for the console cannot be used now. You're on your own for attaching your console to the tub. The reason you can't bolt it down first is because you have to fully install the shifter, then flip the console over so you can attach the cable to the shifter. My set up would not allow me to feed the cable through the hold first. I don't think anyone could.


So this is a picture of the shifter Novak sent me. When I was ready to mount it, I took the plastic housing off, knowing it would not be used. It is held on with 4 screws that go through the Sidewinder tag and into the shifter body. I quickly realized that there was no way to mount the shifter body to the adapter. The adapter has 8 threaded holes in it. That's it.
So back to the phone to call Novak. I figured they didn't ship me a bracket that attached the side bolts of the shifter to the threaded holes of the adapter. Again, instructions would have been great here.

It was pretty funny talking to them. The salesman kept saying over and over that it just bolts on. He was getting pretty frustrated with me. Then told me he would go look at one and call me back.


I jumped on the computer to do a little research and found this little beauty! Another phone call to Novak and we had things straightened out. I can only imagine the things the guys at Novak must say about me. I'm without a doubt the dumbest customer EVER! Well that is until we find out that each time its Novaks screw up. This is the shifter they were supposed to send me. They told me they shipped my shifter to another customer, and I got his instead.


So they sent me the right shifter and I got it installed. Keep in mind, if you do this shifter, you need to grab (8) 1/4-20 x 1/2 screws to mount the shifter to the adapter. For what ever reason Novak wont include hardware in their kits so you are, once again, left on your own.

So with the shifter installed, and after tying up a few loose ends, the Jeep was ready for a drive up and down the street. It shifted through the gears nice and seemed to run well. I then used a neighbors forklift to check the front upper link clearance around the exhaust manifold. I was pretty sure it was going to hit. To my amazement and disbelief it cleared just fine! This was great news as I still had a lot of things left to do and the customer was picking it up last night.
I didn't take any pictures of the flexing or driving it, but it was nice. So we put it back in the garage to finish up some details. And then at about 1am, we loaded it on the trailer and sent it on its way. They're doing a shake down run in Moab this weekend. It will be at the exhaust ship this morning getting that taken care of.

I get the Jeep back next week to finish up the wiring and play with the dash gauges some more. And then build some new front fenders for it.

So far, it's a sweet Jeep. I didn't grab a shot of how it looked when it left, but you'll get the idea from this one.