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LM4 5.3L and 4L60E swap into 2004 LJ

LBarr2002

LIFETIME
SUPPORTER
First trail ride yesterday, home, and quick inspection. It worked pretty good yesterday. It idled around most of the trails with plenty of torque on tap. Tcase stayed in gear. Temp sat at 195 and it didn't push coolant out of the overflow, so looks like that's fixed.

It definitely needs to be tuned, seems pretty rich and could be crisped up.

I knew I still had a little driveshaft to exhaust rub, but I heard a louder rub at times. The front yoke is touching the pipe at times.... probably going to have to get the driver's side exhaust reworked a little.

Tomorrow I'll clean it up and do a little closer inspection. If all is well I'm going to try to drive it to work all week.
 

LBarr2002

LIFETIME
SUPPORTER
I also put the back seat, car seats, and hardtop back on yesterday then took it for a drive. I decided to go ahead and do some highly scientific (stopwatch on my phone) performance tests. With 3/4 tank of fuel it clicked of a blistering 0-60 time of...





14.3 seconds. :shaking:
I've mentioned in this thread about how several people commented it wasn't worth doing with 'just a junkyard 5.3". Any time I hear that, I'll post this picture...

20191215_153424.jpg

7.4 second 0-60 by gps. Full tank of fuel, hard top, and 100 lbs of shit in the back from the uwharrie trip. Also a soft launch. Could probably be sub 7.0s. Cut 0-60 time IN HALF with just an ol' junkyard 5.3 that hasn't been tuned yet.
 

LBarr2002

LIFETIME
SUPPORTER
Just got home from a ride along tune with Charles. His base tune was pretty good but made a few adjustments.

It was lean up top, so fixed that and said it should have picked up some power. He also adjusted the point at which it goes into 'power enrich' mode. Normally the O2 sensors keep air fuel at 14:1. In power enrich mode it ignores the O2s and goes richer, 12:1. This setting base was at 60% load and he upped it to 75%. This should help highway mileage.

At Uwharrie, it was idling fast and trying to 'run away' when just cruising trails. He adjusted the speed at which the idle is controlled by vss up to 19 mph (stock was 4 mph I believe). Because I have my vss in front of the tcase, in 4 low it thinks it's going 2.72 times faster than it actually. Now, compensating for the tcase reduction, it should hold the idle down until 7 actual mph.
 

LBarr2002

LIFETIME
SUPPORTER
Tripp used a different filament for the intake elbow than he normally uses in the printer, but we still weren't completely sure it would hold up to the under hood temps. As a preventive measure, I decided to epoxy the part. The epoxy should give it extra strength and prevent deforming at high temps.

20200105_154557.jpg

One thing we didn't really plan well was all the runs of electrical wires back and forth across the firewall. We ended up with 4 runs of smaller loom. I pulled all of that off and ran a single 1.5" inch loom where it will fit under the tab for the stock harness.

20200105_163734.jpg
 

LBarr2002

LIFETIME
SUPPORTER
Today Tripp put a 200 ohm resistor in my gauge illumination circuit to dim the light to be bearable at night. We also started looking at the cruise control.

I added another half inch of bump stop to see if that would be a temporary fix for my exhaust clearance. Once I make my decision on cage, I'll probably be playing with spring height a little.
 

LBarr2002

LIFETIME
SUPPORTER
Current weight is 4,470lbs, 2130/2340 F/R.

Pre swap was 4,580lbs, 2160/2420 F/R.

I didn't have car seats in and a little less fuel than before, so I'd say about 50lbs difference. That would put it as shedding about 60 lbs.
 
Current weight is 4,470lbs, 2130/2340 F/R.

Pre swap was 4,580lbs, 2160/2420 F/R.

I didn't have car seats in and a little less fuel than before, so I'd say about 50lbs difference. That would put it as shedding about 60 lbs.
Where did you go to weigh it? I think I would be embarrassed to know what my TJ weighs.
 

LBarr2002

LIFETIME
SUPPORTER
15.6 mpg over 209 miles, 3 days commute, one of which included 40 minutes to go 4 miles... Also, the gps speedometer doesn't log miles when it doesn't have gps lock so it doesn't start counting right away and around and around in the parking garage doesnt count. I can live with that.
 
15.6 mpg over 209 miles, 3 days commute, one of which included 40 minutes to go 4 miles... Also, the gps speedometer doesn't log miles when it doesn't have gps lock so it doesn't start counting right away and around and around in the parking garage doesnt count. I can live with that.
TMU! Haha. Glad it’s working out so well for you. I bet it’s a good time. How long before you change out the top end and start making some big HP?
 

LBarr2002

LIFETIME
SUPPORTER
TMU! Haha. Glad it’s working out so well for you. I bet it’s a good time. How long before you change out the top end and start making some big HP?
I'm hoping for a long, reliable, life the way it is. It doesn't need any more power without bigger axles and probably tcase, or at least building the case with wide chain and 6 planetaries.

I really enjoyed the tuning session with Charles.
 
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