Out with the Sprintex, In with the LS3... MoTech Swap

I wanted to get a thread started for my project. It is mild compared to most of the Jeeps I usually see in this section. However, I think it will fit my needs quite well. I'm in Kansas City and don't do any rock crawling or anything major. It's my daily driver and it gets driven through fields occasionally to get to a decent place to go shoot!

It's a '14 that I put a Sprintex SC on this winter. Unfortunately, after a few months I really wasn't satisfied. The power was good, but drivability was pretty bad. Gary and the guys at Sprintex tried to get it right, but the diablosport tuner just isn't capable enough to fix all the issues. Additionally, I didn't feel like being a Guinea pig. The shifting was never really satisfactory. So I looked for proven solutions to increase power...

Now for the LS3... The Jeep is currently at MoTech in the capable hands of Robbie and his team. They are putting in a new LS3 and 6L80. It's getting all the usual stuff to go along with the LS3: HD driveshafts, radiator, exhaust, AeroForce gauge, and the cruise and tap shift module. Here are a few of the most recent pictures that show the progress so far. I'll be sure to add more as I get them.

http://i1033.photobucket.com/albums/...psjhhv7gze.jpg

http://i1033.photobucket.com/albums/...psh8uhjbdj.jpg

http://i1033.photobucket.com/albums/...psq4zsxikm.jpg

http://i1033.photobucket.com/albums/...psiywnesne.jpg

http://i1033.photobucket.com/albums/...psao2kkwyq.jpg

http://i1033.photobucket.com/albums/...psxs94v1ie.jpg

And here's one from our trip down...

http://i1033.photobucket.com/albums/...pswoi1rfew.jpg

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Originally Posted by rgeorge33

I wanted to get a thread started for my project. It is mild compared to most of the Jeeps I usually see in this section. However, I think it will fit my needs quite well. I'm in Kansas City and don't do any rock crawling or anything major. It's my daily driver and it gets driven through fields occasionally to get to a decent place to go shoot!

It's a '14 that I put a Sprintex SC on this winter. Unfortunately, after a few months I really wasn't satisfied. The power was good, but drivability was pretty bad. Gary and the guys at Sprintex tried to get it right, but the diablosport tuner just isn't capable enough to fix all the issues. Additionally, I didn't feel like being a Guinea pig. The shifting was never really satisfactory. So I looked for proven solutions to increase power...

Now for the LS3... The Jeep is currently at MoTech in the capable hands of Robbie and his team. They are putting in a new LS3 and 6L80. It's getting all the usual stuff to go along with the LS3: HD driveshafts, radiator, exhaust, AeroForce gauge, and the cruise and tap shift module. Here are a few of the most recent pictures that show the progress so far. I'll be sure to add more as I get them.

http://i1033.photobucket.com/albums/...psjhhv7gze.jpg

http://i1033.photobucket.com/albums/...psh8uhjbdj.jpg

http://i1033.photobucket.com/albums/...psq4zsxikm.jpg

http://i1033.photobucket.com/albums/...psiywnesne.jpg

http://i1033.photobucket.com/albums/...psao2kkwyq.jpg

http://i1033.photobucket.com/albums/...psxs94v1ie.jpg

And here's one from our trip down...

http://i1033.photobucket.com/albums/...pswoi1rfew.jpg

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WHOA! that is insane. You really did it fast.

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Originally Posted by JeepLab

WHOA! that is insane. You really did it fast.

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Yeah, it probably seems pretty fast, but this is my daily driver. I wasn't content being a Guinea pig while they tried to figure out the tune. It was especially frustrating during the cold winter months. I had a few codes and the shifting was never great... I'd rather spend the money, get it right, and enjoy my Jeep.

Unfortunately, I don't believe that any of the affordable power adders will work well with the stock transmission. Since none of the tuners have broken the code for the W5A580, we can't address the trans parameters. We're trying to fool an adaptive transmission that's calibrated for 1bar atmosphere readings to deal with a 2bar setup. I found it to be unpredictable and frustrating. The "lift-to-shift" condition is an absolute joke... No modern vehicle should be plagued by this.

At this point, I'm just looking forward to getting it back and driving with the stock GM tune. The stock maps for the LS3 and trans should be plenty to haul the jeep around, while doing so in a civilized manner. I'll certainly post up with my feedback and thoughts.

I hope it all goes well. I know I'm getting jealous. Just a tad...

is this engine in and functional?

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Originally Posted by FLIPmeOVER

is this engine in and functional?

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The engine is in, but not functional yet. The motor mounts are welded in and the engine is set. They'll attach the transfer case, install the exhaust, attach the harness to all the sensors, and finish up a few other things, then the body gets dropped. Robbie hopes to get it started later this week or next. It should be completely finished in the next couple weeks.

I cannot wait to hear this thing. Your gonna HAVE to race baumann.

whats the weight of this powerplant vs. the hemi?

What kind of power do you expect this to deliver?
What kind of fuel economy?
How about the braking?
i am not being critical I would just like to get some feedback as to why someone would do this much work and spend this much money for so little? I understand the frustration with the SC but add that to the price of this and WOW

Quote:

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Originally Posted by boosted1

What kind of power do you expect this to deliver?
What kind of fuel economy?
How about the braking?
i am not being critical I would just like to get some feedback as to why someone would do this much work and spend this much money for so little? I understand the frustration with the SC but add that to the price of this and WOW

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Because when it comes to power mods we care about power and how it is implemented. We care less about price. And having a power mod that is "almost right" doesn't cut it. It's that simple.

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Originally Posted by gbaumann

Because when it comes to power mods we care about power and how it is implemented. We care less about price. And having a power mod that is "almost right" doesn't cut it. It's that simple.

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Very well stated... I have nothing to add to justify my decision.

To the other questions:
Power: I'm not sure what kind of power I'll have at the wheels but I picked up the 430hp crate LS3, so even if conditions are not completely optimal, it should make over 400hp/400tq. Additionally, the 6L80E is a very efficient, low-loss transmission. The transfer case is a stock jk unit with a modified input shaft, so from that point back, the parasitic loss will be the same as any other jeep. Regardless of the peak power, this motor has a great power curve and it uses stock tuning. It will be smooth as silk whether its 5 degrees or 105 degree outside and the shifting will be as good as any stock Chevrolet.

Fuel Economy: The LS swapped jeeps have been reporting better than stock fuel economy (if you can keep your foot out of it). I suspect this is because of the extra gear (.67 high gear ratio) and the fact that the engine makes great torque lower in the rpm range. It stays out of the PE mode, which keeps the fuel mixture leaner. However, we drive bricks, so it will never compete with the Prius.

Brakes: I have the teraflex big rotor kit, but the overall weight shouldn't be much more that what I'm pulling out. The pentastar/W5A580 are lighter than the LS3/6L80, but the sprintex supercharger added a fair amount of weight. Weight is one area where the LS motors do very well. I'm having 35x12.50r17s mounted while it's at Robbie's shop, so we'll see how the brakes perform. The big rotor kit was designed to combat extra weight and larger tires up to 35".

Hope those answers are helpful.

It's getting closer. I received this video from Robbie today. It's the first test start.

https://youtu.be/vmHVPUe38c0

Super incredible change. The tranny goes too? is the new one an 8 speed?

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Originally Posted by FLIPmeOVER

Super incredible change. The tranny goes too? is the new one an 8 speed?

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Yep... The trans is now a 6L80E. It's a 6 speed. Here's the ratio:

1st - 4.02
2nd - 2.36
3rd - 1.53
4th - 1.15
5th - 0.85
6th - 0.67

do people say "boss" anymore? The LS swap is "BOSS".

It's about ready to come home... Here's the latest from MoTech.

https://youtu.be/CpwuFaJTwBM

Ive been hemming and hawing about a power mod forever. I think i may just skip it all and go LS.

It's been a while since the last update. The LS3 is amazing. Lots of power, smooth delivery, and the mileage hasn't been terrible. It's been 15-18 mpg, but I have 35's and 4:10 gears. I'm much happier than I was with the Sprintex. I think the Sprintex would have been a better option if my Rubicon was a manual. The 6L80 trans I've got now is wonderful: smooth and predictable. Here's a couple pics:

http://i1033.photobucket.com/albums/...ps566ttwyb.jpg

http://i1033.photobucket.com/albums/...ps6phefykf.jpg

you have to change that sticker. the "rubicon" decal has to go.

maybe MOBICON (motech)?

Hows this swap going? any engine codes?

Hows this thing running? When power mods happen and guys go quiet, its not normally good news.

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Originally Posted by Rexx19

you have to change that sticker. the "rubicon" decal has to go.

maybe MOBICON (motech)?

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Taken care of... No room for the Rubicon decal anymore. I picked up a new hood that will be painted in mid-September. I'll have some good pictures once it's painted, but here's the something for now:

http://i1033.photobucket.com/albums/...psw0hzyaiu.jpg

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Originally Posted by Pznivy

Hows this swap going? any engine codes?

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Quote:

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Originally Posted by Yoinkers

Hows this thing running? When power mods happen and guys go quiet, its not normally good news.

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It's running great; no codes, smooth as could be, and plenty of power. I've had a couple minor issues, but nothing major. The cruise does not come on occasionally, but Motech is working on an update for that. My transfer case has a slight leak, but I'm going to change out the seals this weekend. I'm also going to re-work the exhaust and install some good high flow catalytic converters. When Tallant's Hot Rods paints the hood, they're going to do the exhaust. I'll be using the Vibrant GESi metal substrate OBD-II cats and stainless mandrel bends w/ stainless tubing. I'll try to be more timely as I get those things done. I'll also try to get some better pics of the finished product!

Give us a better shot of that hood. Looks great.

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Originally Posted by JeepLab

Give us a better shot of that hood. Looks great.

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Here you go. I'll have a couple more, once it's painted. I have an appointment with the paint booth on 14 September.

http://i1033.photobucket.com/albums/...pshgnqvf19.jpg

http://i1033.photobucket.com/albums/...pslo7ukgqz.jpg

http://i1033.photobucket.com/albums/...pstobxjzit.jpg

http://i1033.photobucket.com/albums/...psphcz9ojj.jpg

http://i1033.photobucket.com/albums/...psdr2zy4dc.jpg

Its beautiful. Really well done. How about a sound byte ?

is there an intake?

this may be the most beautiful jeep ive ever seen.

Thanks for the complements, guys. I still don't have a good video with sound. I'll put it up here when I do. I picked it up from Tallant's Hot Rod shop in KC on Friday with the hood fixed and painted. They also got a new exhaust fabricated with 2.5" pipes from the manifolds to the muffler and a single 3" out the rear. It uses all stainless pipe, mandrel bends, two Vibrant GESi cats and a Magnaflow muffler. It sounds nice and I believe it flows really well. However, I'm done improving the jeep for a while... I'm sure I'll do little things for maintenance, minor stuff, and I've got a new MoTech module on the way with updated firmware to address an intermittent cruise control issue. Other than that, it's done (for now). As always I've got some pics. Here's the hood all painted and polished up.

http://i1033.photobucket.com/albums/...psgkc66hhc.jpg

http://i1033.photobucket.com/albums/...ps3iw8f5ej.jpg

http://i1033.photobucket.com/albums/...pstn1zuult.jpg

http://i1033.photobucket.com/albums/...psrymhawxi.jpg

http://i1033.photobucket.com/albums/...ps7lcnuw2j.jpg

http://i1033.photobucket.com/albums/...psbhsgl8il.jpg

http://i1033.photobucket.com/albums/...pscuqsctg8.jpg

someone else just got a sprintex in this forum, any tips for issues installing?

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Originally Posted by Rexx19

someone else just got a sprintex in this forum, any tips for issues installing?

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yes that would be me and i would certainly appreciate any tips!

I will say the the installation manual is really quite good. However, you'll find that the bolts on the back are difficult... My hands were sore for days after that. Take your time with those. Smooth and easy is fast.... Don't forget to put the long bolts through the top before setting the sc/top manifold on the lower manifold. Also, lay out the hose spring clamps and make sure you use the correct clamps on the right hoses. I initially didn't and had a couple leaks that I ended up fixing with normal screw type clamps. I posted several pics on another thread that may be helpful to visualize the process. Good luck... If you want to pm me, I'll give you my direct email address if you want to reach out with questions.

we had to work around the back of the engine with the mag install, it is a pain to get around back there.

Quote:

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Originally Posted by JeepLab

we had to work around the back of the engine with the mag install, it is a pain to get around back there.

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X2! It took a couple of 1/4" drive extensions put together with a universal joint to snake onto some of the intake bolts for my MAG install.

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Originally Posted by rgeorge33

If you want to pm me, I'll give you my direct email address if you want to reach out with questions.

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thanks! will do if i hit any snags when i install it next week