A sulfurish smell from the exhaust is usually a clogged Catalytic Converter. Especially under acceleration the smell would be amplified. I'd take it off and look at it. You should be able to see a small open area, about the size of a quarter, maybe a little bigger of light. If you can't, it's clogged and your options are to gut it with a long screwdriver and hammer or buy an aftermarket one. I did the gutting option since I don't have smog checks, plus I didn't have the $$ to spend on a new one. I will eventually. Chris