LMG to L94 swap question Smog (California)

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Shackman7878

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I have a 2013 Tahoe SSV the 5.3 LMG is on it way out. Was looking at swapping to the L94 6.2 but keep the DOD and AMF due to living in California.

Question would it be a plug and play deal I can keep the LMG 5.3 tune factory tune and run the L94 6.2 engine and pass emission testing, Then once emission testing is done I can tune it for Factory L94 tune. Searched and can't get a straight answer most post I can find everyone removes the DOD and AMF.
 
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petethepug

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Jasper sells a CA/Smog legal 6.2L L9H (non AFM) clone I’ve heard. You’d use your existing ECU. Use hypertuners or equivalent to tune out the offending software that’s no longer needed to control the AFM that’s hangs around these motors like the reaper.

Mr. Speedy smog would be none the wiser that the displacement went from 5.3 to 6.2L. The tuner could also make a L9H base tune to satisfy the 2013 CAFE requirements. As long as your documents show the replacement motor is 2013 or newer and it passes smog with same or cleaner, u r set for another 200k 6.2L (s)miles.

You can even put in a call to have a DMV CAFE tech call you and they’ll cut through all the red tape and happily get you to a newer, cleaner, bigger motor.
 
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Dustin Jackson

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@Shackman7878 You can pass smog with an AFM delete, I just did mine again recently. I would be more curious about the motor swap than anything but from my experience as long as it looks like it belongs and there are no check engine lights and the emission monitors are set you should pass with a AFM deleted 6.2 if that's your goal.
 

Marky Dissod

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... looking at swapping to the L94 6.2L, but keep the DOD and AFM due to living in California.
:puke:
... can't get a straight answer. Most post I can find, everyone removes the DOD and AFM.
If everyone else is getting away with it, you can too. Stop living in fear.

Use, or at least start with, the proper OE tune for the corresponding engine, year round.
GM's OE LMG 'tune' was not designed and not ever meant to operate any L94 or L9H.
 
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Shackman7878

Shackman7878

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@Shackman7878 You can pass smog with an AFM delete, I just did mine again recently. I would be more curious about the motor swap than anything but from my experience as long as it looks like it belongs and there are no check engine lights and the emission monitors are set you should pass with a AFM deleted 6.2 if that's your goal.
my main reason for the conversion is more power LMG HP:310 Tq:335 L94 HP:403 Tq:417.
block LMG Cast Iron L94 is Aluminum from a lot of spec checking there is some good and bad with this swap.
For now looking at options when the LMG dies can I put a L94 or put a rebuild LMG back in.

If I go L94 and move out of California will do the DOD and AFM delete.
 
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Shackman7878

Shackman7878

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:puke:

If everyone else is getting away with it, you can too. Stop living in fear.
I don't want to deal with something I cant smog, or visiting a Referee every other day with "Fixes", Went to a local college with a Ref on site and seeing the same 8 people coming back for "Smog Tech" got the serial engine number was wrong, wrong manual transmission was down to gear ratio, One guy had to come back 4 times to prove this new car was all electric due to California saying it was a Hybrid, So many lifted trucks that can't dyno due to tire size and list goes on and on. This was in 2008 - 2010 and can't believe it has got any better since then.
 

Marky Dissod

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I don't want to deal with something I cant smog, or visiting a Referee every other day with "Fixes", Went to a local college with a Ref on site and seeing the same 8 people coming back for "Smog Tech" got the serial engine number was wrong, wrong manual transmission was down to gear ratio, One guy had to come back 4 times to prove this new car was all electric due to California saying it was a Hybrid, So many lifted trucks that can't dyno due to tire size and list goes on and on. This was in 2008 - 2010 and can't believe it has got any better since then.
Then you've been surrounded by the wrong people.
If you look again, and still can't find one person besides @Dustin Jackson who has successfully defeated V4 mode AND passed smog,
then we can both blame your bad luck.

Does not change the fact that more and more people pass CA's smog test after disabling / defeating V4 mode every day.
I really hope you find THOSE people before you find too many more of these sad stories.
Bon chance.
AFM is not part of the emissions system.
The sooner you find other Californians who understand and live this truth, the better.
 

Dustin Jackson

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I am not the first to do this nor will I be the last, here is an entire thread about successful California Smog with AFM delete.
 

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