These engines are not loud because they are low compression so I decided to run a straight exhaust header. I had this one custom made by K.M. Model Aircraft Components. It is a nicely made aluminum header and was very reasonable. I messed up on the measurement and had to have a spacer made but it should be all one piece. Anyway, because of the low compression the best way to get the most both performance wise and cost wise is to run a gas/glow mix. Many may disagree with this but I know what it has cost to build this engine and I didn't have to spend a lot on an EI and there is no timing adj. required to be able to flip start this engine which was a goal for this project. The total cost of converting to glow (not including the nitro fuel) is about $40. which includes the adapter, plug, some batteries a switch and a locking glow plug cap. For bench testing I just left my Hot Shot glo-driver attached to the plug. It will take some time to get the needles adjusted right and these engines need to warm up a bit before they will take more throttle but after a little priming with the choke closed it starts after a few flips and pops and goes right to idle. I am turning a 20x10 MA Schimitar prop but hopefully it will turn a 22x8. As soon as I get some tach readings I'll post them.