LLY: Critique this tune? Anyone?

[LLYCrewCab]

Hi guys, I just bought a used LLY, my first Duramax. Its seems to make ok power but also seems like it has some "rattle" to it? Hoping one of the guys could take a look at his and give me some feedback?

I had a buddy download the tune file for me, he said something like he was amazed it wasn't locked?

 

[LLYCrewCab]

sorry file was locked

 

[PureHybrid]

Whoever wrote it, made it very overfueled (3300us). Pulse table and boost/vane tables could use some finesse. Timing base seems ok, fuel pressure looked stock but I didn't double check, also I didn't peek at every table, just basic stuff. I assume this tune smokes like a train.

The rattle is probably just the fuel pressure coming up and/or pilot shutting off. Hell my truck rattled stock.

 

[bcbracing]

I agree, pulsewidth is too much on top. Also timing is getting a little intense, 30 degrees at 2800rpmis a little much, suprised it hasnt cracked a piston yet. I'd sure hope this is a newbie that made this tune and not a shop selling this junk :thumb::roflmao:

 

[S Phinney]

I will start by saying that the person that tune it needs to reevaluate how they tune. The rattle is coming from entirely too much timing under 50mm3. The fuel pressure is extreme with running the 3300 usec. Timing on the big end is on par for the usec but like I said that is extreme. Could easily damage the motor and would run better with less fuel and timing. The fuel pressures need addressing as it is stock and that is where tons of performance would come from. I have seen worse from big name tuners, if you can imagine that. So, it would not surprise me if it came from one of those guys either. If your going to keep it and want it to be fun, durable and drive great then invest in good tuning.

 

[dirtydieseldan]

Go ahead and look at getting new tuning. Stick with a reputable name too, i had a stint with bad tuning then Zach at Starlite diesel came to the rescue. Believe me it'll blow your mind when you retune it, it's like having a brand new truck.