What can be done to strengthen the 722.3 and 722.5 (overdrive) transmissions.
I intend to do a few upgrades to put a few more horsepower to the wheels and I would like to ensure the least amount of problems.

I have a 87 300SDL with a 722.3. I intend to put in an intercooler, change the turbo to a larger Variable Geometry unit, possibly have a performance modification to the IP and put in a 722.5 five speed.
If I do everything the total HP should stay below 300 probably about 250.

All in all a lot of work but it should be fun.

My concern is that the Variable Geometry turbos make more boost at lower rpm nearly eliminating the turbo lag, but also making more torque at lower rpm which as I understand it is harder on the transmission.

I think the transmission will be the first part of the project. I know that I can get a 722.5 with the shifter and controller,(I think the price I’ve been quoted is a bit high but it is doable if I cannot find a better deal). I think I may need a speed sensor from the donor car to feed speed info to the electronic overdrive controller but am not sure on that part yet. The drive line will need to be shortened, that’s easy.

So how does one bullet proof a 722.? transmission? What parts and were do you get them?

__________________
Don Martin
Bakersfield, CA
87 300SDL