The LS Swap Begins

beaufrusetta

Self-Proclaimed TJ Drag Race Champ
Supporting Member
Joined
Jul 8, 2019
Messages
152
Location
Gilbert, AZ
First off - if my wife ever sees this thread - I've got to thank her for...let's just say for putting up with me and my excitement over this. I ended up winning my 2 fantasy football leagues, and the bigger pick-em NFL league this year and walked away with a pocket stuffed full of cash. First thing I said to my wife (note that I didn't ask - I'm much more of a 'ask for forgiveness later' kinda guy), "I'm going to use this money to start the LS swap"...then I started hunting for engines. Finally found one in the price range I was looking for (dirt cheap) and brought it home (5.3 Gen III LM7).

The plan is to maintain as many of the OEM components as possible that I can salvage (rotating assembly, heads, valvetrain, etc), however, I do plan to play around with cam a little. I'm still looking at a bunch of different options, but I will likely stay with one of the OEM LS cams. I'm not looking for extreme HP or massive performance gains...but growing up around hot rods, NHRA, Nascar, sprint cars, and any other redneck style racing you can think of, I really want this thing to sound like a damn race car (obviously not perform like one).

My plan is to keep the NV3550 and NP241, and with an OEM GM manual transmission bell housing + the Novak adapter, from what I've read, I might get lucky and not have to modify my driveshaft lengths...but measurements will tell the real story. I'm not doing any rock crawling, so I don't care for an automatic transmission - even though that 4L60E is like bullet-proof...mostly it is leisurely off-roading here and there, and mostly my 7-year old daughter thinks the Jeep is like the coolest thing outside of JoJo Siwa and LOL Surprise dolls and always wants to drive around with me in it. Actually, my older kids are always wanting to drive it as well...because it's a manual...and that was the biggest reason why we purchased this Jeep a few years back - both the older kids learned how to drive manual with the Jeep, and I'm determined to teach the youngest with this same Jeep as well.

Some pieces I'm currently hunting down (I welcome any suggestions/feedback/contacts for these if you have them):
  • LS wiring harness & ECU (have a guy in Gilbert with a crap-ton of LS parts that I need to go sift through that said he has these)
  • LS manual transmission bell housing (hoping the same guy has this as well)
  • LS3 Corvette block hugging exhaust manifolds (from what I've researched, these should work well and should be cheaper than the Novak ones, but we will see what I can find)
  • Accessories (alternator, starter, AC compressor, PS pump)
  • I'll end up buying a new water pump, thermostat, and oil pump - I feel like that's just the right choice
  • Going to go with the Superior Radiator setup for the Jeep TJ LS swap with their shroud & fan setup
  • Lots of various Novak pieces or rather parts I can get from Novak (transmission mount, flywheel, clutch kit, engine mounts, crank position emulator, etc)
  • Fuel pump from an 05-06 TJ (higher pressure)
  • Haven't researched the fuel injectors yet...but likely just go with the OEM version for the 2002 Tahoe that this came out of
  • Throttle body (DBC)
  • Need to find the specifics I have to modify in order to run the Gen IV TBSS intake manifold I acquired when purchasing the motor
  • Need to also find some clean looking cover to mask the Sloth (from Goonies) looking TBSS intake manifold
  • Will end up having a muffler shop run some custom piping off the exhaust manifolds to shore up the exhaust side of the house
I would also like to share that after a few weeks of research and looking high and low for different answers, I've concluded that I can dodge the emissions bullet in AZ by picking up collector car insurance for the Jeep, which negates the requirement for me to perform emissions testing going forward. My initial quote also came back cheaper than what I pay now, and I can set a reasonable value that's paid out in the event of a total loss of the Jeep.

There's plenty of other stuff that's going to come up, and I'm already mentally prepared for that. Oh...and I'll be pulling the 4.0L out of the Jeep here soon and selling it - so if anyone needs one, it's got 168k on the clock, meticulously maintained, and runs incredibly well for its age. Once I replaced the original fuel injectors and replaced the intake/exhaust manifold gasket...and fixed that damn vacuum leak on the side of the intake manifold...I'd swear it's what this thing drove like when it was new.

Some pics to kick the thread off...trying to get into the machine shop this week for cleaning/honing/measurements/balancing/polishing.

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I'll be following this if you keep us posted.
For sure…I’m really trying to journal it all, in hopes that someone doing this in the future can find it helpful. There are plenty of these posts on the internet, and all of them are missing things that other ones fill in the gaps for. I hope my thread fills in the gap for another build someday… 👍🏻
 
Met a guy today who runs a custom car shop and builds a lot of Jeeps and does V-8 swaps in them. Both magnum and Hemi's and LS. What are you doing for your dash? He told me about a few different options.
He knows a guy who will rebuild your stock dash with GM gauges but it looks like a stock TJ dash but allows you to plug the LS harness into it.
The other option is Dakota Digital now offers a module emulator for the speedo and tach.
 
Met a guy today who runs a custom car shop and builds a lot of Jeeps and does V-8 swaps in them. Both magnum and Hemi's and LS. What are you doing for your dash? He told me about a few different options.
He knows a guy who will rebuild your stock dash with GM gauges but it looks like a stock TJ dash but allows you to plug the LS harness into it.
The other option is Dakota Digital now offers a module emulator for the speedo and tach.
If I ever did a V8 I wanted to keep the stock gauges, so if there's a way to keep them with an LS that would make a V8 swap so much cheaper. Hemi prices have gone insane.

Does module emulator mean it turns the GM BUS signal into something (CCD/PCI) the stock TJ gauges can read?
 
If I ever did a V8 I wanted to keep the stock gauges, so if there's a way to keep them with an LS that would make a V8 swap so much cheaper. Hemi prices have gone insane.

Does module emulator mean it turns the GM BUS signal into something (CCD/PCI) the stock TJ gauges can read?

Yes one signal in and a different signal out.

https://www.dakotadigital.com/index...id=1192/category_id=287/mode=prod/prd1192.htm
You still have to run dual PCM's and sensors and stuff.
 
Met a guy today who runs a custom car shop and builds a lot of Jeeps and does V-8 swaps in them. Both magnum and Hemi's and LS. What are you doing for your dash? He told me about a few different options.
He knows a guy who will rebuild your stock dash with GM gauges but it looks like a stock TJ dash but allows you to plug the LS harness into it.
The other option is Dakota Digital now offers a module emulator for the speedo and tach.
I'm keeping the Jeep gauge cluster. I don't like the autometer clusters...I'd prefer to stick with it looking as OEM as possible. Even my exhaust cut out switch is going in the available slot next to my locker switch...with a custom label "BAMF". Yes...I'm that guy...and I'm not ashamed of it. That's what happens when you raise your kids around NHRA, Nascar, etc... hahahahahaha

Keeping the gauge cluster isn't that difficult. There is an adapter for the oil pressure and coolant temp sensors, so I'll keep those from the 4.0L and keep them attached to the Jeep ECM. I'm sure the GM ECM is going to want that data as well...so I'll need to sort out the wiring for that. Maybe it won't...I dunno...I'm still in heavy research mode right now. I know that it's definitely going to want the sensor values from the O2 sensors at the exhaust manifold...and MAP/MAF...which those will be connected to the GM side. The speedo will be read from the sensor in the transfer case...so I just need that emulator for the tach reading.

I dunno...I've got more stuff to learn. Tonight's learning has been all about GM bellhousings. Did you know that the bellhousings from like the 60's on up will "mostly" fit on LS motors? Seriously...5/6 bolts slap right on, HOWEVER, the crank is 0.400" forward, so the flywheel, input shaft, and pilot bearing have to accommodate. I'm not entirely sure HOW they accommodate, BUT, it's late...and I'm not so much in the math mood right now. I'll do math tomorrow.

Engine is at the machine shop. Likely going to have to bore the cylinders...which means I've got to buy all new pistons/rods...and I didn't want to, but such is life. Waiting to hear back after all measurements and inspections are done.

ECM, harness, throttle body, injectors, and MAF sensor purchased. Oh...and the bellhousing...still have a lot of other parts to purchase.

Hunting for C5 exhaust manifolds. I think I've read in a few places that those hug the block well, and play nice with the clearance post Novak mount installation. I may have to purchase and try them out just to see...and if they don't work, I'm sure I can unload them quick. I'm definitely not interested in blowing $500+ on Novak manifolds. I'm already getting burned on a $292 fuel system kit...that I can source parts for everything EXCEPT that little custom pressure regulator bypass.

Current running total on parts including the engine...I'm at like $3500ish. Not bad considering it will be a completely fresh setup. I expect that to grow...I've still got accessories, fluids, and all the miscellaneous 10% of stuff to buy.
 
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I'm no LS expert nor even close to it I was just sharing some info I'd gotten from someone who does these swaps for a living. The fact there there is someone putting GM gauges into a TJ dash and making it look stock IMO is pretty cool. And it plugs into the GGM wiring which again from all I know about the swaps seemed neat.

The new emulator from Dakota Digital makes it so you don't have to run two VSS from what I understand. Again I've never tried a LS swap and have only read thread where guys were having issues or opted to go with a aftermarket dash. If you know other ways to make all this work GREAT and I look forward to reading about it. Everything keeps changing as time goes on so who knows.

Best of luck.
 
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... Hemi prices have gone insane.

...
Maybe 'cause they are so much way cooler?????

😁

Yes, I'm pointing right at you, Ryan (@Apparition)!!!




(OP, don't mind me. You prolly don't know me well enough to know I'm kidding. I just like giving Ryan shit...)
 
I'm no LS expert nor even close to it I was just sharing some info I'd gotten from someone who does these swaps for a living. The fact there there is someone putting GM gauges into a TJ dash and making it look stock IMO is pretty cool. And it plugs into the GGM wiring which again from all I know about the swaps seemed neat.

The new emulator from Dakota Digital makes it so you don't have to run two VSS from what I understand. Again I've never tried a LS swap and have only read thread where guys were having issues or opted to go with a aftermarket dash. If you know other ways to make all this work GREAT and I look forward to reading about it. Everything keeps changing as time goes on so who knows.

Best of luck.
Oh yeah - I know - I'm grateful for everyone willfully sharing knowledge and appreciate it! :)

I've been a software engineer for like 25+ years...and the signal thing really bothers me LOL. I swear these "computers" that are in our vehicles (even newer model years) are equivalent to Atari systems and just about as hard to work with. I'm really half tempted to build my own emulator from small boards I have laying around that can easily process the input/output of electrical signals. During all of my research lately, I remember finding someone that was attempting this (essentially replacing the Novak emulator), but I didn't save the link - I need to go back and try to find that. It would be awesome to open source that and give folks a much more budget-friendly choice. I'd love to do that with the pressure regulator bypass as well, but...last I checked I don't have any CNC machines chillin' in my garage, so I may just have to bite the bullet on that one. 😂

BTW - I'm going to look up that Dakota Digital stuff just to see what they've got going on...thanks!
 
Maybe 'cause they are so much way cooler?????

😁

Yes, I'm pointing right at you, Ryan (@Apparition)!!!




(OP, don't mind me. You prolly don't know me well enough to know I'm kidding. I just like giving Ryan shit...)
I sooooooo wanted to put a 5.7 Hemi in the Jeep to match my truck, but then I saw the cost of just a used motor that I'd have to break down and rebuild...and that cost nearly what an entire LS swap would cost. Actually...at my current cash burn rate, it's just about the same based on the prices I saw when doing that research a while back. I can't imagine the prices have gone down since then. hahaha
 
Watching. Curious what it'll cost if you dare to keep track.
Yep…keeping track of every dollar spent. I’m pretty OCD about budgeting and tracking expenses…so this project will be no different, and I’ll share.

Parts are starting to roll in. Delivering my entire gaming setup to a new home today to bankroll this project…well, at least 1/2 of it.
 
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