Neal3000 said:
Can you just use the factory transmission like a typical honda buggy?
Billstoy seemed to be concentrating on RWD transmissions / not transaxle buggies. But yes, you can. The Ecotec spins clockwise like most other engines, unlike most Honda engines. So that makes engine orientation / axle choices a little different than a normal Honda transaxle buggy. The styles of auto transmissions are slightly different, too. The GM autos are long, as long or longer than the engine, and sit down to the lower right of the engine next to the oil pan. One output comes out toward the front of the engine and the other comes out toward the back of the engine. On Honda auto transmissions the bulk of the transmission is kind of to the rear and side of the engine with outputs both toward the back of the engine. None of this really matters, it just creates packaging considerations that are different than the Honda transaxle buggies.
Also, none of the force induction engines came from the factory with an auto. I guess GM wasn't too fond of their automatics standing up to the power. I know little to nothing about the manual transmissions. But the automatic that came behind almost all FWD Ecotecs was the 4t45e 4- speed. Its a computer-controlled 4-speed overdrive trans. They had several final drive ratios available through the use of different chain sprocket sizes and differential ratios. They have little to no aftermarket support and have mixed reviews. Some guys are putting 500hp through them drag racing and not having issues. Other guys can't get them to last 100,000 miles behind a stock engine. The Cobalt I am selling has this transmission.
An option I had considered was using a 4t65e instead. It is a FWD trans very similar in dimensions to the 4t45e. GM seems to have felt very good about this transmission because they put it behind the 300hp+ LS4 FWD cars. It is undeniably the most common FWD GM trans in the country. It came behind virtually all V6 FWD cars that they made from the early 90's until recently. It uses the GM60* bolt pattern, so its not a direct bolt-on, but as I stated earlier, its an easy pattern to make your own adapter for. 4-speed OD trans, very stout. It is the TH350 of the FWD world with tons of aftermarket support and like 9 different final drive ratio possibilities. Racing clutch packs, shafts, valves, etc are all made for it. It uses the same / similar control solenoids as the 4t45e (4l60 and 80, too) and has been run with the same TCM's at various points of time. I haven't done the swap but I have worked out the electronics and programming "on paper" and it seems entirely possible to run it using the stock Cobalt computer. It can also be controlled manually via toggle switches and using aftermarket 4l60/80 controllers. This trans is known to hold up to 500hp in stock form reliably, more when built. It is the trans that GM put behind their 1200hp FWD Ecotec drag car. Last time I was at Pull-a-Part I noticed about 50 of these transmissions in cars.