LM4 5.3L and 4L60E swap into 2004 LJ

This morning we did the bumper nut fix above, put the new crossmember in, checked a few things and laid the GM harness out on the motor.
 
I started today off by finishing up the novak tcase cable shifter, smooth as butter.

Then looked at the transmission shifter but that brought more questions than answers.

Then I swapped out the spark plugs and installed the driver's side header. It fits well.

Passenger side the collector hits the upper control arm mount.
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I notched the collector enough to install it, but I can only notch enough to get maybe 1/16" clearance, not going to work. I've thought of a few options.
1) cut the top of the uca mount and replate it close to the arm joint.
2) another set of ebay headers that dump to the rear and use the passenger side out of that set with driver side I have?

Ideas?

Also, the summit plug wires I got dont look like they're going to work on cylinder #3. Also, I put one on a plug, pulled it right back off, and the connector stayed on the spark plug. Now questioning quality of those wires...
 
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Post a picture where I can see more of the engine bay. May have some header ideas for ya.

I could ask my neighbor what he used on his as well.
 
matth_85 said:
Post a picture where I can see more of the engine bay. May have some header ideas for ya.

I could ask my neighbor what he used on his as well.
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That work? Or I can take some tonight. Above the starter, rear dump has the most room. The factory manifold fits well on this side but I dont want tubular header on one side and manifold on other.

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I just saw what the difference is between what I hve and the AA jeep conversion headers. Theirs do not have a flange. So... option #3 could be cut off that flange and extend it a couple inches to get past the UCA...
 
Yeah, I would definitely not run one manifold and one header. Can you run them backwards and dump to the front? I assume you will be tying them together with a Y on one side anyway...

Extending the header would be fine as well.
 
matth_85 said:
Yeah, I would definitely not run one manifold and one header. Can you run them backwards and dump to the front? I assume you will be tying them together with a Y on one side anyway...

Extending the header would be fine as well.
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The driver side will come around the front of the sump and tie into passenger side then back in stock location. Motor mounts are pretty much under the second cylinder on each side so swapping them wont work. I really think the best solution is an s10 swap header on passenger side, but I'm afraid they're swept back too much. The stock manifold is rear dump but points down at the back of the block, these point more back. I'm also not sure if they're 1 1/2" or 1 5/8" primary.

https://www.ebay.com/c/3022537929
 
I've spent most of my "free" time over the past week moving and organizing tools in to my new boxes, but I've got that pretty much done and worked a little on the jeep today. I looked at headers and trans cable again and think I have solutions for both.

The camaro pan oil cooler bypass has a boss that is not drilled, but makes a perfect spot for the jeep oil pressure sensor. The start of the hole is even 21/64 (the size for a 1/8 NPT tap). So after relocating my vice to a rolling cart, because the new toolbox was in the way of it's old location, I knocked that out.

Through drilled to 21/64, tapped, and sensor installed.

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I can't help but wonder if that location will actually give you a true pressure reading. That serves as a "connector" between the out and in ports for the oil cooler used in other applications. If the flow upstream is unrestricted, your pressure may read lower than actual. Without knowing the path of the oil flow, it is hard to say. I have been on the internet trying to make sense out of oiling schematics with limited success.
 
rolledxj said:
I can't help but wonder if that location will actually give you a true pressure reading. That serves as a "connector" between the out and in ports for the oil cooler used in other applications. If the flow upstream is unrestricted, your pressure may read lower than actual. Without knowing the path of the oil flow, it is hard to say. I have been on the internet trying to make sense out of oiling schematics with limited success.
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It's used all the time and there are companies that sell pre tapped plates of you dont want to do it yourself. It should be fine


Besides, the late TJ sensor/gauge isn't a true reading anyway. It acts like a light with a needle attached, either shows "good" pressure, or none, doesnt change with rpm.
 
I got a couple hours of work in today. i dropped the fuel tank, washed under the back of the jeep and warranty returned the pump. Also swapped out the radiator in the grill and it's ready to sit back in place.

Old:
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New:
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Larry, I would consider using the factory location for the oil sensor. I did what you did here on my first swap but it doesn't give you any indication what you are getting at the cam bearings. The CJ buggy was also done this way. It works, but it's not the best. With the LS platform having some notorious oiling issues and it being in off-camber situations regularly I would feel better about running it up top. You can adapt an aftermarket sender to the factory plug hole pretty easy. I think Autometer sells one, and you can solder that into the factory harness.
 
matth_85 said:
Larry, I would consider using the factory location for the oil sensor. I did what you did here on my first swap but it doesn't give you any indication what you are getting at the cam bearings. The CJ buggy was also done this way. It works, but it's not the best. With the LS platform having some notorious oiling issues and it being in off-camber situations regularly I would feel better about running it up top. You can adapt an aftermarket sender to the factory plug hole pretty easy. I think Autometer sells one, and you can solder that into the factory harness.
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I need both sensors though. I've seen some t fitting adapters that go in the stock location, and I have more room back there than I though I would, so that may work.
 
Soo.... I was looking at something unrelated last night and realized my GM harness no longer has the oil pressure sensor plug in it. I just assumed the ecu would need to see it, but it doesn't. It sucks that I've already tapped the cooler bypass, but I guess I'll put a plug in that and move the jeep sensor up to the factory location with an M16x1.5 to 1/8 NPT adapter.
 
LBarr2002 said:
Soo.... I was looking at something unrelated last night and realized my GM harness no longer has the oil pressure sensor plug in it. I just assumed the ecu would need to see it, but it doesn't. It sucks that I've already tapped the cooler bypass, but I guess I'll put a plug in that and move the jeep sensor up to the factory location with an M16x1.5 to 1/8 NPT adapter.
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Quick research agrees with what your seeing, looks like the PCM never knows about oil pressure... Strictly a gauge signal.
 
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