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LM4 5.3L and 4L60E swap into 2004 LJ


The s10 ls conversion headers came in today. The collector touches the starter but it looks like I can make this work :unsure: I'll just need to flatten one side of the collector. Hope to make some progress this weekend.



The flange or tubing? Please don't flatten tubes....would get more out of a manifold than a dented/flattened header...
The three bolt collector. It looks like I just need to flap wheel the collector a little bit. Didnt get to look at it this weekend because we had a yard sale Saturday and something went in my back yesterday and I pretty much didnt move.


I got a few good hours in today. Started with exhaust. The collector on the passenger side hit the boss for the starter bolt. I wonder if this boss is bigger on the aluminum blocks than the iron? Anyway, I was able to round off that boss and have sufficient clearance.


Then I made it look like a Jeep again.

And put plug wires all on.

Then I messed with the transmission shifter. I was able to get full range with the jeep shifter, just need to get a metal bushing for the jeep cable end to be able to tighten the linkage and not bind the cable. Down the road I'll have to make a new comb plate if I want to keep the function of the shifter button, lock in park, etc.

And I replaced the jeep regulator with the novak bypass.

I also got the gm harness routed and everything plugged back in. So next on the list is fuel lines and radiator hoses.
I had hoped to keep the transmission cooler hard lines up to the front of the motor then a short piece of rubber hose, but the cooler ports are on the wrong side of this radiator. After looking at is last weekend, we decided it would be better to run flexible lines and cross over the trans tunnel to the drivers side and come up that way. This will avoid any interference with exhaust routing also.

I ordered the Russell 640520 adapters that are 1/4" NPSM to -6AN. I'll order 1/4" NPT to -6 fittings for the radiator once I see if I need straight or 90°.

Power steering hose... I have to have the tj pressure line end to tuck tight on the box and under the grill, but it's way too long and the bends are wrong on the pump end (threads are correct). Anybody know where to get a custom hose with a factory jeep box end?
There's a place in Augusta that makes custom hydraulic hoses for all sorts of things from super small to really large metric size included. They are on Gorden highway about 2 miles past the Savannah river on the right. They probably could make what you need.