I'm curious as to whether a GM 3.8 L shares the same transmission bolt pattern as the 2.2? If not is it workable to make a mating plate or just impossible?

 

It does not share the same pattern.

With regards to mounting a 3.8 to an ecotec's transmission or an ecotec to a metric transmission, anything's possible with enough time and money. What are you considering?

 

I have a 3.8 Turbo from my Monte Carlo Z34. My brother messed up his motor in his Cobalt. So I thought why waste a perfectly good motor. What kind of machining would be required do you think?

 

I don't know the Ecotec transmissions all that well, but you'll need at least an adaptor plate (V8 Fiero's typically run at least 3/4"), and depending on your setup (manual/auto in each car , etc), you'll need some custom work on the flywheel and clutch splines, or the torque converter.

In all honesty, the hard work isn't the machining. Money and time can take care of that. Getting the motor/trans electronics to talk to the car, and getting the turbo plumbing and cradle/body modifications right will be the hard part. The 3800, as you know is a WIDE motor (and heavy, not including a turbo), so you might have to do some enlarging to the engine bay, as well as other work to the front end.

My suggestion? put a 2.4 into the Cobalt, and save the 3800 turbo for something older/sketchier, like a Fiero, 90's Cavalier, 3rd Gen F-Body, etc., something where the electronics won't be such an issue.