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Discussion Starter #1
Guys it's been about 8 years we have been doing Gen IV LS swaps; we have hundreds out there with over 1,000,000 miles driven.

I haven't posted much recently but our latest developments are worth mentioning. Our Gen IV swap is still awesome, virtually rationalized over the years. Our current Gen IV swap is virtually plug and play, we have eliminated all redundancies. Our Gen III MoTech module controls all sensors, power modes, AC and much more. We have control of the 2011+ Automatic AC as well as the Pentstar cooling fan. The Pentstar cooling fan is compact and powerful and can be retrofitted to an early JK. Recently temps were nearing 120 degrees here and I drove high compression LS3's with plenty of grille obstructions with no issues.

Our Gen III MoTech module is potted and is user upgradeable. Our harness now eliminates the JK engine harness and includes the JK PCM connectors integrated into the LS harness for a clean install. We are fabricating our own harnesses in house for quality control.

The majority of our swaps now use the OE GM accessory drive for both the truck and Corvette engines. Our Jeep accessory drive is still available and soon to be available in billet.

We continue to support the Pentstar JK's with Gen IV engines, even with auto AC as mentioned. We use the stock JK bumpshifter and it can be fitted to an early JK if required.

Big news is the LS Gen V engine. The Gen V engines have direct injection, continuous VVT, high compression, internal vacuum source, aggressive AFM and more. The word is the Gen V engines can run on regular gas and get 15% better mpg than a typical V8.

We have a couple Gen V swaps in progress and we have already run the 6.2 L86. The L86 is available with a 8 speed automatic as well as the 6 speed.

So I'm hoping for big things from the Gen V swap, like 400+ HP on regular gas with mpg in the high teens running 37's.

Were also working on some low cost swaps with a 300+ HP V6. Hopefully we can get an affordable swap out there for guys that can't drop $20k.

Pictures to follow.
 

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Is there anything in the works for a manual transmission option for your engine swap?
 

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The w5a580 auto behind the 3.6L has a 3.59 first gear and a .83 top gear. The 6L80 has 4.03 first gear and .67 top gear. I have heard many people say that even the 5.3L LS is worth it with the 6L80s gearing, and don't waist your money if your just going to replace a Pentastar with a 5.3/4L60 combo.

Now the 8L90 has me interested, it's 8lbs lighter than the 6L80 and it's stronger. Plus it's first great is 4.56 and top gear of .65

Also the Gen V 5.3L (L83) has about the same peak hp and tq numbers as the Gen IV truck 6.2L.

If I had $20k right now I would be all for being a guinea pig for Robbie to do a Gen V w/8L90 swap.
 

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The majority of our swaps now use the OE GM accessory drive for both the truck and Corvette engines. Our Jeep accessory drive is still available and soon to be available in billet.
Have you guys changed the belt routing with the billet Jeep accessory drive?
 

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Discussion Starter #6
Is there anything in the works for a manual transmission option for your engine swap?
Yes we can support manual transmissions. Remember GM did not offer Gen IV V8 manual trucks so we have to make a few changes.

The stock 6 speed works well with a 5.3, have one in the shop now. We also support the NVG 4500 and Tremec in the larger engines.
 

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Discussion Starter #7
The w5a580 auto behind the 3.6L has a 3.59 first gear and a .83 top gear. The 6L80 has 4.03 first gear and .67 top gear. I have heard many people say that even the 5.3L LS is worth it with the 6L80s gearing, and don't waist your money if your just going to replace a Pentastar with a 5.3/4L60 combo.

Now the 8L90 has me interested, it's 8lbs lighter than the 6L80 and it's stronger. Plus it's first great is 4.56 and top gear of .65

Also the Gen V 5.3L (L83) has about the same peak hp and tq numbers as the Gen IV truck 6.2L.

If I had $20k right now I would be all for being a guinea pig for Robbie to do a Gen V w/8L90 swap.
I completely agree the Gen IV/V can transmissions given the LS swap a distinct advantage. It's not all about power it's about drivability and efficiency. Low first gear means easy launch in a heavy JK and tall OD's mean quiet low rpm cruising.

And it's more than that; compared to the 4l60, 65, 70, 80...the new transmissions are low friction, low heat, adaptive and very strong. After driving a 6l80 for a while if you get into anything else it feels wrong.
 

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Discussion Starter #8
Have you guys changed the belt routing with the billet Jeep accessory drive?
Hi Randy, currently most of our LS3's use the GM accessory drive. Our billet LS3 drive keeps the accessories where they are at but has some subtle changes for clearance.

About a year ago we eliminated the crank trigger wheel which allows use to run the Corvette balancer and offsets now. In fact we can, and have, run most of the available GM drives.

This is a subject for argument which drive works better. Personally I feel our drive works better but the cut and bend brackets were time consuming to set up properly and some were not. Done correctly they run great. I have several swaps with over 70k miles, and one with over 100k miles on our drive with no wear issues.

The GM drive is easy to bolt on and readily available at Jegs or Summit, or can be used off the donor engine. Since we run AFM motor mounts we has to make some changes to allow the low offset Corvette AC compressor to fit properly.

On JK's with no lift the AC compressor will come in contact with the UCA with the GM drive. We offer AC brackets that run the stock AC style belt and tensioner to run off the rear balancer groves as GM intended.

Both drives can run smart charging. With the GM drive you can run a E-Rod alternator for fixed charging, works well and is simple. We can run a ECM controlled alternator where it is not in a fixed 13.6-13.8 limp mode; but we prefer to run the smart charging off the JK computer for several reasons. One we can leave the Chrysler diagnostics active for dash functions. In addition the Chrysler network is better suited to determine vehicle electrical load and charge accordingly.

The GM systems also include a current sensor off the battery to determine battery health and more efficient charging, we are thinking of supporting this on the Gen V swaps for maximum efficiency.

Over the years you learn so much about how these things operate and it's all about making the correct choices.

We make our best efforts to keep the swaps upgradeable. If you want to eliminate your crank trigger wheel and run a different drive we offer a stand alone crank module. We offer AC and PS hoses for either drive. One nice thing with the GM drive is the PS resivouir is built into the pump so it eliminates a couple long hoses, in addition the GM pumps seem to work well with hydraulics and do not require a upgraded pump.

Our truck GM drive uses off the shelf GM PS hoses but custom AC lines. The LS3 GM drive uses custom PS hoses and AC lines. Our Jeep drives use all stock lines and hoses slightly molded.
 

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Is there a length difference between the 8L90 and the 6L90? I know the 6L90 is roughly 1.5" longer than the 6L80.
 

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Discussion Starter #10
Is there a length difference between the 8L90 and the 6L90? I know the 6L90 is roughly 1.5" longer than the 6L80.
I didn't measure one but it appears to be the same length as the 6l80, supposedly the 8l80 is 3.6 kg lighter than the 6l80.

I'm not yet sure how much advantage there will be with the 8l80, in a 200 mph car like the Corvette 8 forward gears are good to have, in a 100 mph JK not so sure.

GM rates the 8l80 only 3.5%(up to 5%) better mpg than the 6l80 and the ratios are not far off:

First gear:
6l80 4.03, 8l80 4.56
Top gear:
6l80 .67, 8l80 .65

The 8l80 has been internally modified for lower weight and less oil pumping losses. The 8l80 goes back to a traditional hydraulic controlled transmission but GM claims it can shift faster than a dual clutch transmission. Personally I think the 8l80 is a incremental improvement over the 6l80, going from the 4 speed automatics to the can driven 6 speeds made a huge improvement.

The Gen V engine is evolutionary, not revolutionary. GM has already got the OHV push-rod V8 to virtually compete with the best technology even Europe has to offer; and with less parts for better reliability. The two greatest contributions on the Gen V engine are continuous VVT and Direct Injection.

Direction allows better combustion efficiency which allows higher compression ratios. Injecting fuel at high pressure directly into the combustion chamber means more fuel gets burned in the combustion chamber and not wetting the the intake walls or back of the intake valve. So less CO's and HC's get out the chamber for the emission systems to handle. GM spent over 6 million hours of CAD design on the Gen V cylinder heads because that is where it all happens, the rest of the engine is basically an air pump.

GM was smart and stuck with a traditional low pressure fuel supply to the engine then an internal fuel pump in the engine to step up the pressure, this allows an easy installation.

We all know VVT helps broaden the power band but the current Gen IV engines are discrete VVT. The Gen V engines use contentious VVT to control the cam throughout the power band allowing smoother and more efficient power delivery.

AFM has been stepped up in the Gen V engines and they run a new engine mount to handle it. AFM is more aggressive and the Gen V engine can idle in a 4 cyl mode I am told. I'm not sure this will pan out well in our heavy JK's so we may turn it off in the heavy builds. If you look at the the driver side of the engine you will see a built in mechanical vacuum pump for power brakes. While in 4 cyl mode engine vacuum is low, so like the Pentstar JK's the Gen V engines run an auxiliary vacuum pump. On the Pentstar it is electric, on the Gen V engine it is a belt driven mechanical pump. This means you should not lose power brake assist even on steep trails at low rpm.

I firmly feel the Gen V swap will take the JK to a point no other engine/transmission combination can offer. Direct Injection, 8 speed transmission, CVVT and the simplicity and reliability of a GM power-train.

Even the new V6 engines are putting out over 300 HP so we are experimenting with both the Camero V6 and the new Vortec 4.3 to accommodate a low cost swap for guys that want the latest technology but don't have a big budget.

We continue to stay true to our MoTech module "bridge" and leaving the GM and Chrysler operating systems pure. This has many advantages including redundancies and fail safe stand alone operation. We have some Can bridge functionality now but have chosen not implement it, but you may see some in the future.

I also want to mention the trucks now appear to have a similar low profile intake like the passenger cars use. This will allow us to raise the engine up for better clearance to the suspension and othe chassis components. The Gen V engine also has an offset water pump allowing more clearance for the cooling fan.
I'm not sure if these pictures will show right away they say moderated.

Front:


Driver side, notice vacuum pump. Also notice newly designed hydraulic mount we will support.


Passenger side:
http://www.jkowners.com/forum/members/motech-albums-gen-v-ls-picture45921-gen-v-6-2-ps.jpg

Rear:


First Gen V JK. You guys may remember the Silver Bullet, same guy owns this. This JK has already been built with axles rails, etc....He built this to wheel hard and not worry about scratching it up so it will be a good test for this Gen V swap:


Shop is full, looking to expand already. Notice Steve's LSA JK in front. It is running great(videos hopefully) and I like driving it, hopefully he will be driving it soon. We have to add brake pedal position sensors and some other electronics to support tapshift and cruise with the CTS-V OS. We finally got the WSS, brakes, AC, suspension, hydraulics. interior............finished:
 

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And it's more than that; compared to the 4l60, 65, 70, 80...the new transmissions are low friction, low heat, adaptive and very strong. After driving a 6l80 for a while if you get into anything else it feels wrong.
And that is going from ~3.5 first gear to 4.0. The 8L80 is 4.5... I can't wait to hear the feed back on how that is on the JKs.
 

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Hi I am the lead electrician here at Motech and would like to share some updates. Here is a sample of what the new GM engine harness looks like with the jeep PCM integrated.

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Discussion Starter #13
BTW guys I should introduce Motechtech, he is Mitch. Mitch runs our wiring department and helps R&D our electronics. Mitch has been installing our Gen III electronics for a while now. Mitch has cleaned up the wiring quite a bit for a clean install, the C100 harness is just a small sub harness now as you can see and it plugs directly into the main harness so much of the engine compartment wiring has been eliminated. We have been stringing our harnesses out in house to optimize quality and fit. Maybe Mitch can post some pictures of his LS3 harness, it is a work of art; you can barley see any wires on the top of the engine.

We have two Gen V engine swaps in the works now, a 5.3 and 6.2. I'm curious to see how the new generation 5.3 does in a heavy JK.

Mitch is available for questions, just call the office and ask for him or post questions.
 

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Mitch-

That wiring is a work of art... Here in the Southeast we have water everywhere, louvered hoods to combat the 100*+ days like today, and monsoon rains that come out of no where (2-4" per hour rain fall rates). So how is the water proofing of the electrical? It looks OEM or better but its hard to tell from these pics.
 

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Discussion Starter #16
Mitch-

That wiring is a work of art... Here in the Southeast we have water everywhere, louvered hoods to combat the 100*+ days like today, and monsoon rains that come out of no where (2-4" per hour rain fall rates). So how is the water proofing of the electrical? It looks OEM or better but its hard to tell from these pics.
Our standard harness uses OE weather sealed connectors, every connection in the engine compartment is sealed and we recommend dielectric grease to help dispell moisture and prevent corrosion.

We use high temp automotive grade wire and loom. We add high temp velcro wrap and thermal shielding in the required areas like around the crank sensor and starter.

That being said if you require additional protection for additional cost we can custom build the harness with fire sleeve, silicone tube with marine shrink wrap connections for waterproof joints. This can be costly because it adds many additional hours to the build.

For the most part our standard harness works in most builds but the option to upgrade is there. Building our harnesses in house has the distinct advantage of controlling quality and the ability to customize. Currently we are doing swaps on TJ's, an old Grand Wagonner, YJ, and more. They all start with the base LS harness and get tailored from there. Wiring makes or breaks a swap, it's critical it's done right and we have learned over the years how bad sourced harnesses can be.

Our new generation MT module is very versitle allowing programable inputs and outputs. This means with a standard interface we can have many platforms supported by mere programming. We can adapt the LS to a YJ, TJ, 3.8 JK, Pentstar JK, Toyota, Land Rover, etc.....

The new MT module is potted and has many new features added. Built in rpm module, crank, cam(4 outputs), AC, power modes PRNDL control, ECT, MAP, OP, variable speed cooling fan control, automatic climate control and more....

One important feature is separation and redundancy. First and foremost is safety, we want the engine to run as a priority. We limit dependency between OS's so if there is a failure on one side it won't affect the other. In fact our MT module can be removed and the vehicle driven in a stand alone mode. Recent improvements have added cooling fan and charging system redundancies so there is no dependance on the JK side, the GM side is completely independent and the MT module acts as a bridge.

The wire count on the current swap is similar to a stock vehicle with the redundancies removed. Mitch is going to post pictures of builds we are doing, there has been so many shipped and not documented.
 

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Harness installed

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0606161651_HDR.jpg

Gen V Camaro LFX with six speed auto. It will be test fired next week for the first time. Only 9000 miles on it and it makes 323 horsepower! Harness has been modified already. I feel a good test platform will be my old car:)

13528767_1370038846345094_2514852873622720071_n.jpg
 

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Robbie,

This post may sound like an irritant to you. It might come across as fingernails on a chalk board (ala that scene from Jaws). That is not my intent. Years ago you helped me diagnose an emissions problem with my hemi conversion. Still very grateful for the time you spent on the phone.

I have a 2013 JKUR and I have been patiently waiting for a do-it-yourself kit LS3 / 6L80e conversion kit. The hold up, or so I thought, was the development of the gen III Motech module that simplified the wiring and thus made the conversion straight forward. I even filled out a form someone from your shop sent me so that I would be in queue on the waiting list for the new kit. Now I read, in your first post that the new gen III module is up and running and going into shop conversions.

But I also read that you are branching out and continuing to evolve your product, vis a vis now doing some beta Gen V engine conversions, with 8L80e conversions. While initially I was excited to hear this, after a few moments, that “oh crap” feeling came back. If you are focusing an expanding your in house conversions to include new engines and transmissions as well as expanding into TJ and YJ and other vehicle conversions, that probably isn’t good news for the development of a truly full fleshed out plug and play do it yourself LS3 conversion kit.

I am not talking about a builders kit that other shops can buy and thus do “MoTech” conversions for their customers. I am talking about a kit targeted at the shade tree mechanic audience. Why do I want to do the conversion myself? Well, a couple of reasons. First off, nobody takes care of my stuff like I take care of my stuff. Every time I take my Jeep, or any vehicle into a dealership it comes back with some issue it didn’t have before – scratches, grease stains in the interior, etc. Second, if I do it myself, when it breaks I have some idea how to fix it. Third, having done my own hemi conversion and helped friends with 3 or 4 more, I can say I am pretty comfortable doing an engine swap in a JK. Provided the parts are all there, the instructions are detailed, complete and accurate and the locally sourced parts information is accurate.

When I did the hemi conversions, I used the AEV kit. The AEV kit comes with very detailed, almost completely accurate instructions and a very detailed, specific BOM for locally sourced parts. After doing the first conversion, my friend and I were able to do a hemi conversion in 5 days start to finish. We knew, from the instructions and BOM, exactly how it went together and exactly what parts were needed. There was literally, zero trips to the parts store or dealer for additional stuff. To me, that is the definition of a “conversion kit”. It’s not just the parts, it’s the instructions and the additional parts needed to complete the build.

So where am I going with this diatribe? Well, if you are continuously improving and tweaking your conversion product along with expanding your business to include vehicles beyond the JK, it stands to reason that the development of a top tier conversion kit for the do-it-yourself crowd (crowd? Maybe I am the only one…..) is a low priority. And that is fine. That is a business decision, I get it. Perhaps you want to focus on shop conversions and grow your business by staying on the bleeding edge of the technology (new Gen V motors and trans) and expanding into other vehicles. That makes complete sense. But then just tell me that my multi-year wait for a conversion kit is in vane. I can take it. I will survive. (I have a sports car with a Gen V motor in it.) I will just move on. I will make other plans. Let’s just cut to the chase.
 

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I thought there was a builders kit, but couldn't figure it out on the website. I too will hafta do this conversion myself (with the help of others) for most of the reasons nucleophile mentioned.
 

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Discussion Starter #20
Robbie,

This post may sound like an irritant to you. It might come across as fingernails on a chalk board (ala that scene from Jaws). That is not my intent. Years ago you helped me diagnose an emissions problem with my hemi conversion. Still very grateful for the time you spent on the phone.

I have a 2013 JKUR and I have been patiently waiting for a do-it-yourself kit LS3 / 6L80e conversion kit. The hold up, or so I thought, was the development of the gen III Motech module that simplified the wiring and thus made the conversion straight forward. I even filled out a form someone from your shop sent me so that I would be in queue on the waiting list for the new kit. Now I read, in your first post that the new gen III module is up and running and going into shop conversions.

But I also read that you are branching out and continuing to evolve your product, vis a vis now doing some beta Gen V engine conversions, with 8L80e conversions. While initially I was excited to hear this, after a few moments, that “oh crap” feeling came back. If you are focusing an expanding your in house conversions to include new engines and transmissions as well as expanding into TJ and YJ and other vehicle conversions, that probably isn’t good news for the development of a truly full fleshed out plug and play do it yourself LS3 conversion kit.

I am not talking about a builders kit that other shops can buy and thus do “MoTech” conversions for their customers. I am talking about a kit targeted at the shade tree mechanic audience. Why do I want to do the conversion myself? Well, a couple of reasons. First off, nobody takes care of my stuff like I take care of my stuff. Every time I take my Jeep, or any vehicle into a dealership it comes back with some issue it didn’t have before – scratches, grease stains in the interior, etc. Second, if I do it myself, when it breaks I have some idea how to fix it. Third, having done my own hemi conversion and helped friends with 3 or 4 more, I can say I am pretty comfortable doing an engine swap in a JK. Provided the parts are all there, the instructions are detailed, complete and accurate and the locally sourced parts information is accurate.

When I did the hemi conversions, I used the AEV kit. The AEV kit comes with very detailed, almost completely accurate instructions and a very detailed, specific BOM for locally sourced parts. After doing the first conversion, my friend and I were able to do a hemi conversion in 5 days start to finish. We knew, from the instructions and BOM, exactly how it went together and exactly what parts were needed. There was literally, zero trips to the parts store or dealer for additional stuff. To me, that is the definition of a “conversion kit”. It’s not just the parts, it’s the instructions and the additional parts needed to complete the build.

So where am I going with this diatribe? Well, if you are continuously improving and tweaking your conversion product along with expanding your business to include vehicles beyond the JK, it stands to reason that the development of a top tier conversion kit for the do-it-yourself crowd (crowd? Maybe I am the only one…..) is a low priority. And that is fine. That is a business decision, I get it. Perhaps you want to focus on shop conversions and grow your business by staying on the bleeding edge of the technology (new Gen V motors and trans) and expanding into other vehicles. That makes complete sense. But then just tell me that my multi-year wait for a conversion kit is in vane. I can take it. I will survive. (I have a sports car with a Gen V motor in it.) I will just move on. I will make other plans. Let’s just cut to the chase.
First let me say I have been doing engine conversions since the early 1980's. I have done everything from Porsche's to a Model A roadster. When the 4 door JK came along in 2007 it changed a lot of things. Guys could load up their family into a capable 4WD drive vehicle for a reasonable price, so it was a hit. Chrysler has sold over 1,000,000 JK's and sales are still strong. I'm one of those guys, I had an LS powered 82' Toyota PU I took everywhere. When I got married and decided to have kids that 2 door Toyota no longer worked for me. Fortunately my wife likes to wheel as much as I do so we got a brand new 2009 Rubicon 4 door in very early 2009. It is Deep Water Blue and has all the options. We hated it.

We loaded up that brand new 09' Rubicon JKUR and headed to New York from Vegas. By the time we got to Salt Lake bad things were happening. I couldn't hold the 80 mph speed limit. My wife wanted to know why the engine made so much noise and was laboring. By the time we got to Park City I was crawling at 45 mph screaming the engine in 2-3rd gear. The final insult was I got pulled over by a cop for going too slow and constant speed changes. He let me go when I told him I was almost WOT and that's all I could do.

The rest of the trip was no better, strong winds in Wyoming and Nebraska brought us to a crawl. My wife tried to drive the Jeep in Virginia then gave me back the keys back, she told me we were selling the Jeep when we got back to Vegas.

When we got back to Vegas I realized several things. One my JK was great off road and could hold all the equipment we needed as well as a couple kids. Two there was nothing else out there with live axles, lockers,sway bar disconnect, etc...that would do what I wanted. Sure I could have got an old Rover or Landcruiser but that is not what I wanted. I realized there were lots of other guys in the same boat as me, great vehicle-bad engine.
 
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