If you're building a competition entry or alternate entry for the 2013 AMSOIL Engine Masters Challenge, please take time to check out the revised rules that were posted today. (This is the fifth version, or fourth revision if you're counting. Click on the above link to download a pdf.) Of particular note are the new sections on Fuel Injection (page 19 & 20) pertaining to intake manifolds, throttle bodies, and gaskets, with additional revisions in the muffler, cylinder head, fuel, and water pump sections. Revised section can be found in bold print.