SoK66

That's the stumbling block with the LS swaps. Two of the individuals I mentioned earlier made multiple trips to Robbie's place to get the tunes or functions working. I agree the GM engine/trans combination looks sweet on paper, and the trans is certainly better than the Hemi's old 5 speed Mercedes box. But there seem to be many individual issues depending upon which LS & trans you end up with. A side benefit for those with post-2012 3.6s with automatics, you can just swap the engine and retain your existing trans. Lots to consider.

caryt

Get a kit from John................................and DIY

OCHO BACON

There were times that I just wanted items tweaked and we tuned the thing via our computers with EFI Live , I don't know if you could do the entire tune that way , you could contact him and ask .

I went from Central Florida to Louisiana which is further than you would have to go , just depends on how bad ya want it . Ha.....

Rednroll

Well that seems to be the problem. My previous understanding was that you purchase an LS kit from Motech/Robbie or John and it comes with the ECM with their tunes already in them and all the conversion wiring harnesses.

Now it's starting to sound like that is just a starting point and once you have that all installed, you then need to go visit them in person so they can perform further tuning to make it work right for your setup.

Well what the heck are you having to pay $7K+ for the starter kit if the tune in it isn't right?

un lupis

[QUOTE=Rednroll;4345187]Well that seems to be the problem. My previous understanding was that you purchase an LS kit from Motech/Robbie or John and it comes with the ECM with their tunes already in them and all the conversion wiring harnesses.

Now it's starting to sound like that is just a starting point and once you have that all installed, you then need to go visit them in person so they can perform further tuning to make it work right for your setup.

Well what the heck are you having to pay $7K+ for the starter kit if the tune in it isn't right?[/Q
No that just isn't the case , like I stated before that would be just a stock tune only . Buy a stock Silverado , what you get is a stock tune . Well then you know that a tuner can pull some extra ponies outta'that Chevy . And someone that really knows what they are doing can "Custom"tune even a stock Silverado beyond what a "canned"tune will be able to provide .
It's all context . Please understand that I'm not real good at explaining what is available in tunes but give John a call he even answered my dumb ass questions . Real glad I took the time to talk to him Love the way it ran before the tune , but after well , wow ...

Sixty4x4

My Motech kit is coming with Fedex shipping today or tomorrow. All the conversations with Robbie have addressed my concerns. But to be fair I am going Gen V with 8L90 tranny. 2 Chev controllers with CANBUS interface. All GM computers programmed and Robbie has to simply walk me through the Jeep programming changes to get rid of errors on first start. This will be done via HP Tuner module on my laptop. So am I concerned - no. I should have it all done within 4 weeks and will be able to tally the costs. I am not tuning just staying stock @ 365HP/380Tq to keep the drive train intact.

Rednroll

Keep us updated on how it all works out. That was my original plan to get a Motech conversion kit and pick up a LS engine and trans and all the other necessary parts and do the conversion work myself. However, these problems being reported regarding the tuning has me now concerned but without knowing exactly what was done from the start with those who had problems, I'm curious to learn if they're justified or not.

I'm currently suspecting those problems may have been due to early gen LS conversion kits and Motech has likely worked out the kinks by now with their kits and the currently supplied tunings. The typical problems associated with being an early adopter on products that need to go through a few rounds of getting the bugs worked out.

barongan

Subscribed to this one

Sixty4x4

Rednroll yes the early Gen 4's were an issue but Robbie seems to have these sorted now but he still recommends using the drive by wire Gen 4. He moved on to Gen 5's development so upon advice from the guy in Texas I mentioned way back, I went with the Gen 5. That is what he would do given a new start. And they say the 6 speed auto from Chev is great, but now the scuttlebutt is that the 8 speeds are even better. Also the Gen 5 uses all Chev accessories such as alternator, AC compressor and Robbie provides the CNC brackets for 2012 and up PS pump. So no serpentine issues that also come with Gen 4's. Lots of reasons why I jumped on the Gen 5. Also the base price of the engine and tranny is small compared to the rest of these conversions so not sure why people buy the high mileage motors to try and save a little. The days of backyarders doing these conversions are pretty much over especially for our brothers and sisters Jeepers down south who have to comply with emissions regulations.