NAMBA October 2020 Web.pub

The Nitro Engine – Part 5 (Continued from page 5) The two side ports flow the two incoming streams together at the bottom of the cylinder with their collision resulting in a slow-moving column of mixture up the cylinder. The first improvement on this system is a boost port opposite the exhaust that aims some flow up toward the cylinder head. This is the classic system many nitro engines use. PROPWASH 6 October 2020 Modified and stock K&B 7.5 sleeves More recent engines have used more ports for more flow with better flow control. Porting for a 12.6 cc Stunt Engine Porting for Jim Allen’s 90 Mac 45 Boost Port