Stumbling my way through an LS Swap (4 Viewers)

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I'd really like to stop by and check it out / give a hand if needed. I'm starting the LS planning here.

Sounds good to me! I'll shoot ya a PM.
 
Got back at it this weekend and started by modifying the OEM harness on the RPM gauge to work with the aftermarket VDO. Pretty simple setup and all I have left to do is connect the wire from the BP Automotive harness and the RPM gauge is wired in.

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The BP Automotive harness is worth it's weight in gold. It was a super easy install, with fantastic instructions and every connector was well labeled. My only complaint with the harness would be that it's designed with the ECU mounted in the interior on the passenger side somewhere. That wasn't possible in my situation so I ended up pivoting to mounting it on the driver side fender. This is going to be my daily driver so I don't mind looking at it, plus it's easy to access in case I ever need to replace it. Since there is so much extra wire to let it mount on the passenger side I have a bit of slack coiled up behind the engine, but nothing I can do about it. I would recommend getting it unloomed if possible, as @dbbowen suggests that way you can make the wire runs as short and clean as you want them to be.

I'm following the path of least resistance when it comes to the electrical portion of the swap, so with the ECU now on the driver side fender I mounted the fuse box where the air intake for the carb fan used to be. I also didn't want to drill new holes in the firewall so I took a 5/8 drill bit and increased the size of the hole where the choke cable used to come out of and ran the interior wires through it with a new grommet. If you want to do it this way you have to depin the OBDII wires but that's really easy.

All in all I think the harness routing looks okay. Definitely not perfect but I think it's good enough for government work.

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With the stereo harness finished & the new antenna installed (my old one was broken off) I was able to get the dash put back together. The new stereo looks great with the Torfab metal bracket and it was a super easy install.

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I also installed the new metal glovebox I got from @mr2m1 which fit perfectly. Would totally recommend.

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I still have to hook up a few things & make my new battery cables until I'm done with electrical but am pretty stoked to be where I'm at. Anyone that's done this swap before - did you route a negative cable from the battery to the body with a separate negative cable from the block to an engine mount bolt? Figured the more grounds the better.

By the way do I still need these relays? They are located in the driver side kick panel underneath the emissions control box

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Ive got about 2.5 feet or so of engine harness that is very very very low on the to do list of shortening. Same deal as you, ive got it coiled in the corner of the engine bay.
 
Anyone that's done this swap before - did you route a negative cable from the battery to the body with a separate negative cable from the block to an engine mount bolt? Figured the more grounds the better.
I used this kit from a mud member for my swap. Very burly.

It includes:
Battery negative to fender and motor mount cables
Ground strap from head to firewall
Ground strap from starter to frame
 
I use the factory gm wiring but your engine probably didn't come with it but I also run a ground on both sides from engine to frame one also from the back of the head to the fire wall and one from battery to the fender ground location also one on tye back of the tcase to the under body like factory landcruiser. I also use mil spec battery terminals.
 
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Been sick the past few days but am still chugging away on the wiring. I ended up buying battery cables from @Fourrunner as suggested so am waiting for those to come in.

I got my ECU mounted on the fender using countersunk bolts and a factory PCM mount. I'll be honest, I don't love it's positioning and would like to build a bracket to get it up a little more but it'll work for now. I'm in full send mode as I want to hear this thing run before December, so function over form right now.

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Months before I had even considered the LS Swap I bought a fusible link kit from @CruiserTrash. This thing is really sturdy and I wanted to keep it with the LS. Jim gave some great advice on how to adapt it and it's really easy. I replaced the 70 AMP alternator fuse with a 150 AMP based on a stock alternators max output. I also have a new 6 AWG cable to run alongside the factory charge wiring to the junction box on the right of the motor, and then that will be done.

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The last bit of electrical I had in the interior was the power wire for my electric fuel pump. I was able to route it through the factory grommet for the sending unit wires and then re-loomed it all. The idea is to be able to disconnect both the fuel pump and sender through the access panel. I want the fuel pump to have a good ground so the ground wire will be run all the way up to the engine bay to connect directly to the battery. I thought about cutting another access panel for the pump but decided against it.

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LS Alternator Wiring & Final Wiring Notes
Hit a big milestone last night, I'm officially 95.62% done with all the wiring on the swap. All I have left to do is install my battery cables, and extend the oil pressure & temp sending unit wires to reach the sensors on the LS.

I saved the best bit for last as I hadn't really touched the wiring on the passenger fender at all. There are quite a few plugs and looms on this side including where the fusible link plugs in, the harness that runs to the transmission & starter, washer motor plug and the old alternator wiring. Because of how short some of the wires are I wasn’t able to run it through the fender like I did on the passenger side.

The only part of this wiring that I had to cut was the old alternator wiring – I cut the plug off, heatshrinked the ends and then wrapped it in the harness. The two large white cables that go to a single eyelet on the old alternator were then extended using 10 GA & 12 GA wire respectively. I ran them along with the new 6 AWG cable that I had crimped onto the fusible link box noted above. The fusible link box is mounted on the fender using two holes for the fender apron clips. I wanted to mount it up higher but unfortunately with the new airbox and how short the cable is to factory plug my options were limited.

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I was able to harvest the old loom & harness connectors from the original harness that ran under the oil pan and used those to route these new wires to the red junction box where the LS alternator fusible link connects to. Once I had my lengths right I removed the harness, wrapped it in electrical tape & plastic conduit and did my final install.

It was a little tedious, but these are the charging wires for the new alternator and I wanted to make sure they were routed properly. I also took some old heater hose I had lying around and put it over the part of the harness that was making contact with the motor mount to protect it from wear over time. It’s a little hokey, but I really don’t want any problems with these wires.

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Honestly the wiring was the part of this swap that intimidated me the most, and now that it’s in the rear view it’s really not that difficult. You can make it as complicated as you want it to be based on how clean you want your wiring to look and how you run your wires but as for the connections themselves it’s pretty straightforward. Here’s a list of all the connections and modifications to the original harness that I made on the swap:

BP AUTOMOTIVE HARNESS
  • Connect the harness to all the plugs & sensors on the engine - Bank 1 + 2 Spark plugs, Camshaft & Crankshaft position sensors, temperature sensor, fuel injectors, MAP sensor, knock sensor, & IAC & Throttle Position sensor (If using DBC throttle body)
  • Run the VSS back along the top of the trans to the transfer case. BP Automotive sold an adapter harness that worked with the older VSS that comes with the Jags That Run kit
  • Run the loom into the interior, the only wires I needed were for the RPM gauge, the OBD port, the check engine light, switched ignition for the ECU & fuel pump power

FJ60 BODY WIRING
  • RPM Gauge Wiring (Only if using aftermarket RPM Gauge, you can use the stock one but will need some kind of converter)
    • Stock RPM Gauge Wiring:
      • Black – Gauge Ground
      • Black/Yellow – Switched Ignition
      • Red – Old tach signal wire, can be deadheaded & put in the harness
      • Black/White – Light bulb ground
      • Red/Green – Light bulb power
      • You’ll connect the wire from the BP Automotive harness to the Ignition Coil/Alternator tab on the back of the gauge. My gauge had dip switches and is set to a 4 cylinder as I believe that is what the signal from the ECU is. Will confirm when I start the engine up for the first time

  • ECU Trigger/Switched Ignition Power
    • I used a quality fuse tap plugged into my cigarette lighter fuse (UPDATE - use ENGINE 20 AMP fuse, Cig lighter doesn't receive power when cranking) with a spade connector to disconnect from the fuse tap if I wanted to get it redone in the future. There’s better ways to tap into switched power but this was easiest for me, I’ll probably do it right in the future though using the Cruisercult plug.

  • Check Engine Light Wiring
    • I used the old choke cable indicator in the speedometer cluster for my check engine light. Cut the wires from the bulb and crimp them to the wires coming from the BP Automotive harness
  • Starter Wiring
    • Cut off the old spade connector & install a #10 ring terminal for 14-16 gauge wire. I use the ones with heatshrink from Vatozone. Connects to the starter with a M5 nut & lock washer
    • Run positive cable from battery to positive post on starter solenoid

  • Alternator Wiring
    • Extend the white charge cables to the LS alternator. One is a 12 GA wire and the other is a 10 GA wire. They were crimped into one ring terminal from the factory, I used individual ones as it was easier.

  • Oil Pressure & Temperature Gauge Sending Units
    • Buy the oil pressure & temp sending adapters from Cruisermatt, and extend the wires using 20 GA cable to reach their new spots on the LS. The oil pressure sending unit is on the back of the engine and the temp sending unit will be placed on the passenger side head (see above posts)


This will differ if you are using an electric fan setup or have a DBW setup but this is the gist of what needs to be done and how little of the factory harness you need to modify. It’s really not that bad and I was totally overthinking it before hand. I can’t say this enough – GET THE BP AUTOMOTIVE HARNESS. Customer support has been great, and the instructions and quality of the harness can’t be beat. It’s worth the premium over a cheaper harness.
 
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Fuel System
With the electrical portion of the swap taken care of it was time to move onto the fuel system. There's a ton of different ways to do this, but in my opinion an in tank pump is the most reliable way to do it.

Since I have an FJ60 that didn't come from the factory with fuel injection, the only way I could’ve used my old tank with an in tank pump was to modify it myself and I opted not to do that. I bought a long range 38 gallon tank from Man-a-Fre that was designed for an FJ62. @tmxmotorsports sells an adapter that allows you to use a Tank’s Inc GPA-2 instead of an FJ62 fuel pump assembly which is really convenient. These LS’s only need 58 PSI of fuel pressure so I’m using a 190 LPH fuel pump which will be more than adequate. EDIT - My fuel pressure at the rail is at 45 PSI running and 50 base with the regulator vacuum line removed. This is correct as the Flex Fuel L59's with the regulator on the rail and the return line run at lower pressure.

When you buy the GPA-2 fuel pump assembly make sure you get the gasket separately, it does not come with one. Part # is 3G-N.

I had to modify the factory sending unit by brazing on an extension rod that comes with the kit. I used a c-clamp to get everything set up and then used a torch and solder to get it done. I wrapped the plastic float in a soaked rag to protect it from getting melted by the torch and that worked really well. Not the best brazing job in the world but it's solid enough for me.

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Here's the adapter that tmxmotorsports sells. Worked like a charm

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The Man-A-Fre tanks are kind of notorious for having brackets that aren't welded correctly or in the wrong place and my tank also had that problem. It was a pretty easy fix though, just had to slot out the holes on one bracket a little bit more and it fit right in so not a huge PITA. It's a little bit annoying but considering it's $500 cheaper than the LRA tank I can live with it. Everything else bolted up just fine and overall I'm happy with it.

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I did a good amount of research on fuel lines and decided to go with a steel hard line down the length of the frame and then Earl’s Vapor Guard fuel hose from the hard line to the tank and the fuel rail. It’s really good stuff and easier to put together than braided line, just cut it with hose cutters and slip the fitting in and clamp it with a fuel injection clamp. If it’s good enough for high horsepower applications I figured it was good enough for my stock 5.3 in an old brick.

Here's the 3/8 hard line bent up to match the factory contours. Ends were flared with a 37 degree flare to work with the AN fittings

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I've been trying to use as many off the shelf parts as possible on this build so I bought the necessary adapters to work with a stock fuel filter out of a 2003 Tahoe. Just need a 3/8 quick disconnect & a -6AN to M16 x 1.5mm adapter. I didn't use any AN fittings on the return lines, just secured 5/16 hose with fuel injection clamps.

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I'm really hoping to be able to hear this thing run for the first time this weekend, I feel like I'm really close to that first startup with open headers!
 
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With the electrical portion of the swap taken care of it was time to move onto the fuel system. There's a ton of different ways to do this, but in my opinion an in tank pump is the most reliable way to do it.

Since I have an FJ60 that didn't come from the factory with fuel injection, the only way I could’ve used my old tank with an in tank pump was to modify it myself and I opted not to do that. I bought a long range 38 gallon tank from Man-a-Fre that was designed for an FJ62. @tmxmotorsports sells an adapter that allows you to use a Tank’s Inc GPA-2 instead of an FJ62 fuel pump assembly which is really convenient. These LS’s only need 58 PSI of fuel pressure so I’m using a 190 LPH fuel pump which will be more than adequate. When you buy the GPA-2 fuel pump assembly make sure you get the gasket separately, it does not come with one. Part # is 3G-N.

I had to modify the factory sending unit by brazing on an extension rod that comes with the kit. I used a c-clamp to get everything set up and then used a torch and solder to get it done. I wrapped the plastic float in a soaked rag to protect it from getting melted by the torch and that worked really well. Not the best brazing job in the world but it's solid enough for me.

ms4Tao.jpg


Here's the adapter that tmxmotorsports sells. Worked like a charm

EBE5L0.jpg


The Man-A-Fre tanks are kind of notorious for having brackets that aren't welded correctly or in the wrong place and my tank also had that problem. It was a pretty easy fix though, just had to slot out the holes on one bracket a little bit more and it fit right in so not a huge PITA. It's a little bit annoying but considering it's $500 cheaper than the LRA tank I can live with it. Everything else bolted up just fine and overall I'm happy with it.

1Fkfok.jpg


I did a good amount of research on fuel lines and decided to go with a steel hard line down the length of the frame and then Earl’s Vapor Guard fuel hose from the hard line to the tank and the fuel rail. It’s really good stuff and easier to put together than braided line, just cut it with hose cutters and slip the fitting in and clamp it with a fuel injection clamp. If it’s good enough for high horsepower applications I figured it was good enough for my stock 5.3 in an old brick.

Here's the 3/8 hard line bent up to match the factory contours. Ends were flared with a 37 degree flare to work with the AN fittings

QRbbAA.jpg

mAXBvY.jpg


I've been trying to use as many off the shelf parts as possible on this build so I bought the necessary adapters to work with a stock fuel filter out of a 2003 Tahoe. Just need a 3/8 quick disconnect & a -6AN to M16 x 1.5mm adapter. I didn't use any AN fittings on the return lines, just secured 5/16 hose with fuel injection clamps.

NPC4JR.jpg

123Y36.jpg

cqBcFN.jpg


I'm really hoping to be able to hear this thing run for the first time this weekend, I feel like I'm really close to that first startup with open headers!

By the way - now that I have all the tools to bend and flare these lines I would be open to making a few more and offering them as an off the shelf solution if there's enough interest.

Redoing my fuel supply line with an actual hard line and not just AN hose is on my list. That looks great!
 
With the electrical portion of the swap taken care of it was time to move onto the fuel system. There's a ton of different ways to do this, but in my opinion an in tank pump is the most reliable way to do it.

Since I have an FJ60 that didn't come from the factory with fuel injection, the only way I could’ve used my old tank with an in tank pump was to modify it myself and I opted not to do that. I bought a long range 38 gallon tank from Man-a-Fre that was designed for an FJ62. @tmxmotorsports sells an adapter that allows you to use a Tank’s Inc GPA-2 instead of an FJ62 fuel pump assembly which is really convenient. These LS’s only need 58 PSI of fuel pressure so I’m using a 190 LPH fuel pump which will be more than adequate. When you buy the GPA-2 fuel pump assembly make sure you get the gasket separately, it does not come with one. Part # is 3G-N.

I had to modify the factory sending unit by brazing on an extension rod that comes with the kit. I used a c-clamp to get everything set up and then used a torch and solder to get it done. I wrapped the plastic float in a soaked rag to protect it from getting melted by the torch and that worked really well. Not the best brazing job in the world but it's solid enough for me.

ms4Tao.jpg


Here's the adapter that tmxmotorsports sells. Worked like a charm

EBE5L0.jpg


The Man-A-Fre tanks are kind of notorious for having brackets that aren't welded correctly or in the wrong place and my tank also had that problem. It was a pretty easy fix though, just had to slot out the holes on one bracket a little bit more and it fit right in so not a huge PITA. It's a little bit annoying but considering it's $500 cheaper than the LRA tank I can live with it. Everything else bolted up just fine and overall I'm happy with it.

1Fkfok.jpg


I did a good amount of research on fuel lines and decided to go with a steel hard line down the length of the frame and then Earl’s Vapor Guard fuel hose from the hard line to the tank and the fuel rail. It’s really good stuff and easier to put together than braided line, just cut it with hose cutters and slip the fitting in and clamp it with a fuel injection clamp. If it’s good enough for high horsepower applications I figured it was good enough for my stock 5.3 in an old brick.

Here's the 3/8 hard line bent up to match the factory contours. Ends were flared with a 37 degree flare to work with the AN fittings

QRbbAA.jpg

mAXBvY.jpg


I've been trying to use as many off the shelf parts as possible on this build so I bought the necessary adapters to work with a stock fuel filter out of a 2003 Tahoe. Just need a 3/8 quick disconnect & a -6AN to M16 x 1.5mm adapter. I didn't use any AN fittings on the return lines, just secured 5/16 hose with fuel injection clamps.

NPC4JR.jpg

123Y36.jpg

cqBcFN.jpg


I'm really hoping to be able to hear this thing run for the first time this weekend, I feel like I'm really close to that first startup with open headers!

By the way - now that I have all the tools to bend and flare these lines I would be open to making a few more and offering them as an off the shelf solution if there's enough interest.
Did you plug the tanks inc vent on tye top of there module?
Thanks for giving me a plug I don't advise the adapter everyone that has purchased one has all been word of mouth here on the forum and I am very thankful for that!
 
Redoing my fuel supply line with an actual hard line and not just AN hose is on my list. That looks great!

Thanks man! It's not perfect, but pretty good for a first timer. Having a good flare tool & bending tool makes all the difference in the world. I used a Ridgid Model 377 for the flares and an Imperial 370FH tube bender.

Did you plug the tanks inc vent on tye top of there module?
Thanks for giving me a plug I don't advise the adapter everyone that has purchased one has all been word of mouth here on the forum and I am very thankful for that!

I left it open, figured another vent wouldn't hurt anything but I can easily slap a cap on it. I have pretty good access to it through the sending unit hole.

Happy to advertise for ya man, it's a really great solution and the Tank's Inc stuff is fantastic.
 
Thanks man! It's not perfect, but pretty good for a first timer. Having a good flare tool & bending tool makes all the difference in the world. I used a Ridgid Model 377 for the flares and an Imperial 370FH tube bender.



I left it open, figured another vent wouldn't hurt anything but I can easily slap a cap on it. I have pretty good access to it through the sending unit hole.

Happy to advertise for ya man, it's a really great solution and the Tank's Inc stuff is fantastic.
I piped that extra vent on the tanks inc in tank pump back into my vent hose that goes up the frame rail into the engine bay to the charcoal canister. It was the fuel tank vent plus the tanks inc vent.


The result was liquid fuel pouring out of the line at any fill amount above half full on the tank. I removed it and capped that vent and left only the fuel tank vents and its been happy ever since. @tmxmotorsports is right about capping it. Trust me
 

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