2006 LS2 w/ 4L65E Transmission not shifting properly.

[AWEBB]

HP is on it's way... I am working on a 55 BelAir with the engine and transmission from an 06 GTO. Two problems the car currently has: One, it doesn't seem to have a rev. limiter (I can send you the video) and two, the transmission does a quick shift when WOT around 20 MPH. Transmission hits 1st for a fraction of a second then immediately to second when it should be winding out in 1st and shifting about 200 rpm below the limiter to 2nd. It shifts from 2nd to 3rd @ 6500 rpm so the problem is just with the 1-2 upshift. I have programmed a 4L65E with the Supermatic TCU software from GM Performance (1960 Corvette w/ LS3-4L65E), so I am quite familiar with proper transmission settings. I am hoping the HP software can help me solve both of these issues. Anyone? Thanks in advance.

[CSTune]

If you can post your file, I can take a look at it and see if anything looks out of place. A log of the stacking shifts would help as well, but not entirely necessary.

[AWEBB]

Thank you CSTune! I will have the file this week, HP will be here tomorrow.

[AWEBB]

55 BelAir Stock Tune.hpt

[CSTune]

Have you already updated the tire size and gear ratio in the tune? Anyway you can make a log of the problems you are experiencing?

[CSTune]

I see that the current file has the rev limiter at 6600 RPM. How high are you able to rev the engine?

[AWEBB]

I posted the stock info. I have changed the tire size to actual diameter 26.66" and the gear ratio to 3.75 in the file I am working with but haven't flashed it back to the car. Yes I can log this issue, possibly tonight. (weather permitting)

[AWEBB]

I will log the limiter issue also. In P and while driving.

[AWEBB]

The tire size and gear ratio fixed the shifting issue and the other issue was the within the tac. The tac reads about 400 rpm off when compared to the software. On a good note, the speedo was exact. When I logged a 1st gear WOT the software showed 6679 rpm, so the fuel is being shut down at 6600 but the tac on the car read a little over 7K. So from a programming point of view this car is done. Thank you for the help CSTune! Onto the next car.

[CSTune]

Awesome, glad you got that resolved. Good luck on the next project!

[HartRod]

What gauges are you using? You can adjust your tune setting to work with the tach.

[AWEBB]

Sorry it took so long. The gauges are Classic Instruments. Thanks,

[HartRod]

Look under Engine->General and change Tach -> frequency and put 15 in High and low resolution.