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Higher horses, higher revs & even higher torque, a streetable LJ engine swap

Fenders and grill came back off for easier access for some things. Some oils leaked on the grill so I degreased it and the radiators out in the lawn.

20221005_wash-grill.jpg
 
Before removing the fenders I marked them for some additional trimming. I learned during my previous trips off road that they didn't have enough clearance when the frame flexes.

20221008_mark-fender-trim.jpg
 
Where wiring will be routed close to the exhaust I depinned connectors and sleeved them in DEI heat sleeving (DEI 10916).

This video shows how to depin many different connector types:



20221009_depinned.jpg


20221009_heat-sleeve-wiring.jpg
 
The overflow tank I ordered from Motion Raceworks (32-102) fits the space perfectly! It sure arrived fast!

I made a mounting bracket:

20221012_reservoir-bracket.jpg


And installed:

(I'll be replacing the plug with a black one.)
20221012_coolant-reservoir.jpg
 
This is my battery cable wiring diagram:

20221013-battery-cable-diagram.png


I had previously installed a "big 4" wiring kit since my OEM wires were getting old and tattered. Now that I'm doing it myself and taking care to size things appropriately, I'm finding that I can get by with much smaller and lighter wiring. I've definitely cut out a few pounds of wires so far!

All of my battery cables and lugs are marine grade tinned copper. The split loom is also self extinguishing. I did this in an effort to reduce corrosion and potential fires.

I started crimping cables with the Ancor 703040 crimping tool. If anyone is knowledgeable, I'm curious to know if these are good crimps. They're definitely solid, but I don't like how they smear the lug near a couple of the corners.

20221008_lug-crimp.jpg


I wired the SPAL fan power wire to a 60a resettable breaker from Blue Sea Systems and grounded the fan to the grill.

20221012_battery-cables.jpg
 
You second 4 strap from chassis to battery is a bad idea.

You're introducing a parralel ground path for your accessories which isn't ideal.

I'd suggest deleting it and running it all off of the engine block ground wire. Up this one to 1/0 or 2/0.

Your crimps look fine to me. If you have room, you could double crimp the lug and avoid this issue.

Also, no kill switch ?
 
Bebop said:
You second 4 strap from chassis to battery is a bad idea.

You're introducing a parralel ground path for your accessories which isn't ideal.
Click to expand...

I copied the OEM configuration that Jeep used on the TJs. I'll have to look more into this since it's possible that I've deviated from OEM configuration with my other changes.

Bebop said:
Also, no kill switch ?
Click to expand...

I'm just copying OEM here too. The keyed ignition will kill the engine.
 
Bebop said:
You're introducing a parralel ground path for your accessories which isn't ideal.

I'd suggest deleting it and running it all off of the engine block ground wire. Up this one to 1/0 or 2/0.
Click to expand...

Well, this sent me down a massive rabbit hole of research.

Best reason I can figure is that Jeep added this ground loop to the TJ was for redundancy to deal with the possibility that somebody could accidentally leave one of the ground wires loose. And they presumably and obviously knew that none of the OEM components would have an issue with the ground loop.

Compared to the random Jeep owner, there's significantly less possibility of me leaving a high power ground disconnected and starting a fire. So safety from this aspect isn't as much of a concern for me.

So, as you suggested, as far as I can tell there's only upsides to removing the battery to firewall ground and upsizing the battery to engine ground since all current will be running through it.
 
I didn’t mean to send you in a whirlwind of research, but I try to apply some basic principles to all my harnesses and star point grounding is one of them.

And since you referred to Haltech videos, here is one from them explaining the issues with a parallel ground path.

 
Bebop said:
I didn’t mean to send you in a whirlwind of research, but I try to apply some basic principles to all my harnesses and star point grounding is one of them.

And since you referred to Haltech videos, here is one from them explaining the issues with a parallel ground path.

Click to expand...

Np. It's good to learn. Is it still ideal to ground the accessories to the body at various points or should those be star point? Packaging that would be difficult.

What'd you have in mind for a kill switch?

Updated diagram:

1665797976926.png
 
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toximus said:
Np. It's good to learn. Is it still ideal to ground the accessories to the body at various points or should those be star point? Packaging that would be difficult.

What'd you have in mind for a kill switch?
Click to expand...

As long as every single element has only one path to ground, it's absolutely fine to wire them to the body. Path would be accessory --> body --> body to engine cable --> engine to battery cable. Just don't wire anything to the body AND the battery directly.

For a kill switch (and not a battery switch), I usually use a blue sea 5510 or 6010. One circuit for the alternator and the other one for your main power cable.

For a battery switch, use a 9003e or 6004, put it on ground and it'll do the job excellent.

Winch gets wired direct to battery, no switch. If you want to add one (smart), get another 9003e and put it on the power cable.
 
I think I found my first thing I don't like about packaging the LS: the starter wire.

How are you guys routing the power cable?

This is the best I've come up with so far. I think I'd connect it at the alternator stud and use cushion clamps to hold it to the block.

20221015_163428.jpg


20221015_163445.jpg
 
The way your battery is located, it should be no big deal to run a wire to by going along the firewall then down to the bellhousing area then to the starter.

If you don't want to install a kill switch, add a wire from the starter along the engine block, then up following the cam cover.
 
Also this :

20221009_heat-sleeve-wiring-jpg.591730


Why go through the trouble of de-pinning everything if you're not putting heatwrap all the way to the connectors?
 
Bebop said:
The way your battery is located, it should be no big deal to run a wire to by going along the firewall then down to the bellhousing area then to the starter.

If you don't want to install a kill switch, add a wire from the starter along the engine block, then up following the cam cover.
Click to expand...

I like the idea of a kill switch, I just don't know how to package it yet without having to open the hood to access.

To further simplify, maybe I'll move the starter to the battery side of the 140a block.

1665885511239.png
 
Bebop said:
Also this :

20221009_heat-sleeve-wiring-jpg.591730


Why go through the trouble of de-pinning everything if you're not putting heatwrap all the way to the connectors?
Click to expand...

They're hidden behind the starter and/or heat shield that goes between the exhaust and starter. Except for the knock sensor (bottom right) that's farther away from the exhaust.
 
toximus said:
I like the idea of a kill switch, I just don't know how to package it yet without having to open the hood to access.

To further simplify, maybe I'll move the starter to the battery side of the 140a block.
Click to expand...

Alt goes direct to battery. Jump it to the starter.

Leave the accessories out of the loop.

Edit : ECU power goes direct to battery.
 
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Few more things:


1) Use this :

TS-BT2-250RD-dimensions-600w-600x600.jpg


On your firewall.

Send a 2/0 cable from the battery positive to it.

On the exterior send a cable to the alt then starter (or vice versa).

On the interior, send the cable to your buss bar.



2) ECU ground also goes to battery.





What is the PDC ?
 
Bebop said:
1) Use this :

TS-BT2-250RD-dimensions-600w-600x600.jpg


On your firewall.

Send a 2/0 cable from the battery positive to it.
Click to expand...

This is to get power to an interior kill switch? So I'd need 2 of these studs, one to the switch, one from the switch?

Bebop said:
What is the PDC ?
Click to expand...
Power Distribution Center. Aka OEM Jeep fuse and relay block which is still being used for some things.
 
toximus said:
This is to get power to an interior kill switch? So I'd need 2 of these studs, one to the switch, one from the switch?
Click to expand...

I thought you didn't want a kill switch so my suggestion didn't incorporate one.

Power Distribution Center. Aka OEM Jeep fuse and relay block which is still being used for some things.
Click to expand...

Do you need a 8awg wire for those things ?
 
I don't see the need for the 60amp breaker.


Why is there a 140amp block just for the ARB ?
 
Bebop said:
I don't see the need for the 60amp breaker.


Why is there a 140amp block just for the ARB ?
Click to expand...
The breaker is for the SPAL fan.

The 140amp block can be reduced if only the ARB is on it.
 
You just don't need a 140amp block.

What spal fan needs a 60amp breaker ?!?! PDC is a fuse / relay box. Use that instead.
 
The ECM has 3 tiny grounds they don't need to go to the battery. Gm grounded them all to the block. 1 pass head 1 drive head one drive side block.
 
Winchested said:
The ECM has 3 tiny grounds they don't need to go to the battery. Gm grounded them all to the block. 1 pass head 1 drive head one drive side block.
Click to expand...
2 grounds are for injectors and coils. These can go to the engine.

The ECM ground should go to battery to avoid transient voltage issues.




I know people have wired them to chassis ground no issues.

I know people who had their ECMs do stupid shit because of it too.
 
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