There are a few designs that use high performance auto v8 and v6's modified for use in aircraft.
An Australian company makes scaled down reproductions of Spitfires. They supply optional aluminium radiators, ducting and fixings(including electric cowl flaps).
Check out
http://www.supermarineaircraft.com/O...l%20Extras.htm
You never know you may be able adapt it to your project.
Cheers and all the best.