If you want apull start, the nicest and cheapest and fastest is the Ofna Hyper .21 8 port. 119.95@ UltimateHobbies.com. 138.95@ Nitrohouse.com. Then decide between an RB Concepts "63" or "86" tuned pipe, based on your researched descision. The Hyper 8 port comes w/ a nice header, you could try a CVEC pipe.
Then if you really want team speed,send it over to SmeltzRacing@netscape.net
and get the $100 internals mod job!
Thats what I'm going to do for my Hyper 7, or go for a (approx): $260-270 RB WS7, $300-350 RB C5 or Sirio .21 Buggy. With these you will also need a header for $40-50 busks. I recomend a two piece exhaust over the phoeny one-picers (that are really 2!).
Peace, and good luck! Ethan Mayethanmay@aol.com