Engine Startup Procedure rebuilt 2009 6.2l Denali (Rookie Question)

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Rokjhn

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Picked up a 2009 Yukon Denali AWD with a seized engine recently from a friend that wanted to scrap it. I happened to have a freshly built 6.2l from a 2013 Yukon XL that I was going to put in my 2011 Avalanche, but decided to use it for the Yukon instead. The rebuilt 6.2 has new bearings, pistons, rings, LS7 lifters (AFM\DOD Delete) and Texas Speed L92 VVT Stage 1 Truck Camshaft in it. This is my first time swapping an LS engine as my previous engine swap experiences were over 40 years ago. Can I just start the new engine with the existing computer or do I need to have any tuning done initially? Planning on a custom tune at some point (Black Bear maybe?). Any other advice or suggestions would be appreciated.

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Joseph Garcia

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I cannot personally assist you with your issue, but other members of this Forum much more knowledgeable than me in this area will chime in.
 
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Rokjhn

Rokjhn

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To be clear:
that camshaft requires a tune
disabling or deleting cylinder confusion (that's what I'm calling it) requires a tune
One tune for both.
The 2009 Truck didn't come with AFM\DOD so the computer the existing computer doesn't have it. I did the kit on the rebuilt engine, i.e. lifters, cam, valley cover.
 

Geotrash

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I figured it would, but would it need tuning before initial startup?
The original engine in the '09 should be the L9H (flex fuel + VVT but no DoD) with essentially the same larger injectors as those in the '13 6.2. Since the '13 6.2 has a non-DoD cam in it already that retains VVT, it shouldn't *need* a tune to run. But it will need a tune to run smoothly and get the most from that cam.
 
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Marky Dissod

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I figured it would, but would it need tuning before initial startup?
Would the aftermarket cam NEED tuning before initial startup?
No way to be sure. Geotrash may be right - it may run well enough to drive to the tuner.
That said there's a significant chance that it will run suboptimally by enough for you to be very glad that you are driving to the tuner.

I'd get it tuned by pcmperformance. He's really good at mail-order tuning for aftermarket cams. But that's me.
 

Marky Dissod

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You mentioned an aftermarket camshaft. That camshaft requires a tune.
I figured it would, but would it need tuning before initial startup?
So I did a little research on this subject.
Long story, short:
The ignition and volumetric efficiency tables are expecting the OE cam.
The closer the camshaft is to the OE camshaft, the easier it will be to drive it to the tuner.
The further the camshaft is from the OE, the more urgently that cam will need to be tuned for PRIOR to driving.
 

Foggy

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You will need to load a tune for the camshaft in it before you start it
It may or may not start up and then run like crap if it does run
AT very minimum you will need to change the required base airflow minimum
for it to run... Then lots of other little things...
you'll need to find a tuner or remote tuner and purchase HPTuners software and credits
to tune it yourself
 

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