Yeah, the TMS shorties, which were designed for the E36. They should bolt up ok, and I think they'll fit, and Vorshlag is planning to work on some custom catted downpipes for them for me. They should help with torque (ok, not hard vs. stock!) which is what I need for autocross purposes, as we don't spend much time at high revs.
Some recent emails I've received indicate I may not need to go quite that exotic, but we'll see, awaiting clarification from the appropriate rules folks...