gentlemen the graph shows that the x-15 is as fast to 60 with the 2.93 rear as the a-4 with the 3.15 and at the same time nets about .75 mpg better mileage. no data is shown for the rest of a 1/4 run but the consensus based on other comparable vehicles is a probable .3 to .4 drop in total et for the quarter which should be VERY close to the quarter mile times of the mn6's.This is going to be a major improvement in the vette

 

I certainly agree it'll be a huge improvement for the car. Once again, is it definite that it will be in the 06 model or is that still up in the air?

 

All you guys think is straight line. Has anybody even thought of the improvements you will see in a race track!

 

I go on a lot of winding roads & can tell you that an A6 would absolutely improve performance & more importantly the "fun" factor when zipping around the curves. I love my A4, but when an A6 comes out, I'll be having one

 

And think of all the mairrages the A6 will save!

 

If you look at the gear ratios of the 6L80, you can see that a 6L80 with a 2.73 has significantly lower gearing in the first four gears compared to a 4L60E with a 3.42. 5th gear in a 4L80 with a 2.73 is very close to 4th gear in a 4L60E with a 3.42 (2.32 vs 2.39)

4L80 gear ratios: 4.02 2.36 1.53 1.15 0.85 0.67
4L60E gear ratios: 3.06 1.75 1.00 0.70

The 6L80 also incorporates what GM calls Performance Algorithm Shifting (PAS) and Driver Shift Control (DSC). PAS lets the electronic transmission controller override the automatic gear selection during closed throttle high lateral acceleration maneuvers, rapidly downshifting with the release of the torque converter clutch for smooth powering up when the throttle is reopened. Driver Shift Control allows the driver to sequentially shift gears manually via the gearshift lever.

There are two factors about the 6L80 that could have a negative performance impact but both should be able to worked around.

First, it is rated for only 430 ft-lbs of engine torque. Assuming a 20% drivetrain loss, that equates to about 344 rwtq. Better than a 4L60E (288 rwtq) or 4L65E (304 rwtq) but you still will probably want to beef it up if you have a H/C or even a cam only, let alone a supercharger.

They also have continued the use of torque management to smooth out shifting and prolong transmission life. During shifts, “power is instantaneously lowered, then ramped back up carefully to make gear changes virtually unnoticeable”. That has got to hurt performance but I would think that it could be easily programmed out (like can be done with the 4L60E).

Hopefully, the 6L80 will be adaptable to my C5

 

Just had my wife's Lexus RX330 five speed automatic transmission computer reflashed. I guess this means reprogrammed. We had one of the first five speed RX's built in Japan. We special ordered it about a year and a half ago and waited 4 months for it to be built and shipped to us.

The first 6 months or so of production automatic five speeds took a while to downshift and Lexus took notice of the complaints. They issued a technical service bulletin that reprogammed the transmission computer. I just had the TSB done and damn this transmission does the job now for a 3800 pound SUV with 3.3 litered engine.

These newer muti speed transmissions will surely be programmed to give us what we want. More POWER to the People! I know the General won't let us down with the newer transmissions. Faster and more miles per gallon. The future is bright. Andy

 

3.42 in a factory auto? Are you talking about an auto that someone has installed 3.42s in or is there an actual factory car being compared somewhere that has 3.42s in it?
As I'm sure you already know the autos only come with 2.73s or optional 3.15s.