Depends slightly on what engine it has on it, and hugely on what you want out of your Lemons experience. As for the car, they can be made pretty capable on track, and the 2.4L LD9 Quad4 makes pretty good power for the size. The 2200 does not, by any stretch of the imagination, and the revs will need to be kept low (very, very low) if you want it to survive. Luckily, with a manual, you wouldn't have a crappy GM econo-car automatic to keep cool, and you've got a lot more leeway to keep the revs low. You can do basically anything you want with it, and you'll pretty likely stay in Class C. If it's the 2200, one of the much better V6s (3100, 3400, 3500, 3900) is a relatively straightforward and documented swap, if you decide you need more power after a few races. Less stuff to break on the Pontiac, and you can find parts in pretty much any junkyard or auto parts store in the US.
An E28 is a pretty good way to go if you must race a BMW in Lemons, but, it's still a BMW. Sunfire, on the other hand, doesn't get done very often, and will get you much more leeway with any upgrades you might want/need to make (believe it or not, there *is* an enthusiast community for crappy old GM FWD cars).
Semi-Sentient Centenarians
1996 Buick Century - we upgraded our crappy GM sedan with parts from a crappy GM minivan.
"It's got a van motor, a 220 cubic inch plant, it's got van tires, van suspension, van shocks. It's a model with the catalytic converters ripped out so
it'll run good on regular gas. What do you say, is it a racecar or what?" - Blues Brothers, Probably