I am planning for the future gtp tranny. Will it work. Downloaded a GM pdf file and the tranny number is the same. Gm list the parts required to make it very tough.

a 4T65E-HD from a Cobalt should bolt up.

would the manual tranny work from a cobalt then? or is it not a 4t65e?

Thats good. The GM PDF file is the step by step procedure for turning your colbalt into a 1000 hp rocket. The PDF brakes it down into the require hp you are looking for all the way to 1000hp.
The mods include every GM part number required to make the tranny bullet proof. Cooool....

Where is this PDF file?

BTW, are you sure the Cobalt has the same gear ratio at our HD trannies? Something to consider looking into.

The manual won't hold up to the torque of the stock L67.

Gear ratios can be changed....

If this is what I think it is.....
This has been long awaited for.... They will be offering a differential that we've all been drooling over for better than a year. Comparable to the Quaife, or Torsen... Same concept being a Torque Biasing Differential.

Well, it's got my attention. Also, their differential will only have me drooling if it's affordable, unlike other models available.

Take a look and let me know what you think. Maybe its to much for the average racer but for those with the turbo and like to rip out the tranny..

http://www.gm.com/company/gmtunersource/html/race_shop_build_book.htm

From the PDF file

Starting with the heavy duty or
supercharged application of the production transmission,
the gearbox is modified into a three speed transmission with
driver shift control utilizing an aftermarket performance
torque converter. The changes have proven to be reliable
behind a 600 hp engine and track proven behind a 1000+
hp ECOTEC engine.

I am sure there are some part number we can use to build up our trannies...here is another quote.

TCI and CompuShift offer automatic shift controllers that will
operate the 4T65E Transmission. These are excellent
choices for street strip applications.
An inexpensive alternative for drag racing and occasional
street use is the MSD Programmable shift controller part
number 7559. (Fig. 234) This controller was developed to
shift a Lenco type transmission. With a little ingenuity it can
easily be adapted for use on the 4T65E transmission.

Any idea if we can use something like a Shrifter on the 4t65e?

uh, I still didn't catch if the cobalt manual tranny will bolt up.

Anybody?

BTW, I noticed in end of the PDF: Differential and Final Drive Assembly 4.0 gears. #CPT712

From what I saw, the Cobalt has to use a conversion plate for our tranny to bolt up to it. So, I'd say no.

Would some of parts on the list work? What is the most common brakes on the GTP tranny.

Yah, I saw that.... I also noticed that they list it as a Torsen Diff, which is already available at a premium price... I was hoping GM would have their own version.

Wait..... now that I think about it.... the final drive gear ratio doesn't have anything to do with the differential... If I'm wrong, please correct me, but the only variable that I know affected by the components on the differential is the speed sensor.

I e-mail the address on the PDF file. Gmsportcompac replied when I asked them if we could use any of these parts.

"The automatic transmission that we use in our drag racing program is from the Pontiac Grand Prix. It is the 4T65 Hydra-matic. There are two ratios in production, and we offer a streetable upgrade to one of them: 35/35. This is a set with upgraded gears and a single, wider chain (there are two thin chains in production - - for reduced noise). The price is $725.

We also offer a 3.29 torsen differential ($1295) and a 3rd gear clutch pack ($35). I don't know if you really need those or not. Quiafe also offers an aftermarket diff.

These parts can be purchased directly from GM Racing only. They require pre-payment by certified check or money order. They are not covered under any vehicle warranty."

Your right as far as I know. Only gears and chain need to be swapped for new gears, not the diff. But damn, 4.0 would make for some fast acceleration.

And do bupkis on for the top end. I'd bet if you put that gear ratio in the GP that you'd top out in MPH well before the end of the track essentially killing your ETs.

As for the quaife those things have been on back order for years now.

i would still love to see a manual trans for the gtp...that would definately make me smile a bit...

I could suffice with paddle shifters for fun. Being auto, with our ability to play with the pcm, is perfect for dragging.

1000 hp?

I dunno...