GR8TALK

Also the condition you are describing may be a product of the strategy for torque limiting relative to gear. The vettes run into this all the time. It will yank timing and pull the throttle shut. This makes for some real crappy shifts. If you need more on this topic let me know. I can ramble for days.

TurboYukon

Would the transmission be "torque limiting" on a stock trans tune, or is that something that is custom tuned for the guys with big HP in cars, so they aren't just sitting there spinning their tires constantly?

I talked to the guys down at CBI and it still has a stock tune in it. They didn't experience the issue with the trans, but I put the 24's on it after they tuned it, so the small difference int the tire overall diameter could be just enough to throw everything off just enough to freak the trans out every once in a while. It shifts flawlessly sometimes, and only periodically hangs up on the one-two WOT shifts. Either way, they are going to take a look at it and we may end up sending off the PCM to get unlocked and tune the transmission.

madmann26

iTrader: (7)

It's probably the ETC kicking in and yanking it back. Torque limiting is standard on just about all GM products, so yes, it's there and active.

GR8TALK

I would definitely get the tcm unlocked and change the calibration. It is worth its weight in gold. The speed control termination torque management strategy will wake things up considerably not to mention other small changes that will really contribute to driving the turbo.

gonzo 6.2

iTrader: (8)

GR8TALK
Dont you think his 600HP seems light? 6.2 whipple guys are near that with headers and pulley down to bring boost back to about 8-9 lbs.

You may not chime in on this but, to do all that work and to not tune the trans or not know what needs to be done to tune trans seems suspect.If they thought it shifted ok not tuning trans and ship it,might think of a new tuner.

gonzo 6.2

iTrader: (8)

GR8TALK

What is your experience if you dont mind sharing,if you want to remain incogito thats ok too,you could be a well know tuner from a big shop and want to fly under the radar.

TurboYukon

Thanks for the advice. I really appreciate it!

TurboYukon

I talked to the guys at the shop and they had talked to hp tuners back when they finished the truck up, and their wasn't much they could do with the trans at the time. Hp said they could ship the truck out as the stock trans tune would work, but was not ideal. The 2017s have different software that makes them a huge PIA to hack into compared to the 15-16s. I think the ability to unlock the trans tuning came out after they finished it up.

As for the 600hp, that was on a loaded mustang dyno. They tend to read about 70 hp lower than a dynojet on a full size truck because they compensate for weight and air resistance.

The truck also has a majority of the stock manifolds including the cats, and I have a cut out before the main converter. That was by my request because I wanted to be able to pass emissions and safety inspection later on down the road. The tune has timing set pretty mild, as I wanted a fighting chance to not have the whole thing go boom if something goes wrong with the meth kit at some point in its life.

Maybe I'm wrong, but It definitely feels strong, and I'm used to driving some quick vehicles. If I'm just a tune away from another 100 hp, I'd be willing to send it somewhere, but considering al the intricacies of the build and the fact it was on a loaded dyno I doubt there's much more juice to squeeze out of her.

gonzo 6.2

iTrader: (8)

Facebook says they finished June 9 2017

TurboYukon

That was the last and current iteration of the truck and tune with the methanol. It was originally without set up without methanol and a lower boost setting. They must have come out with the trans unlock in between time.