I tried the 13x8 and it netted me about 250 rpm more. Last night I checked my timing and I was at 30btc. Sorry for reporting wrong earlier. I moved it to 28btc and will check today.
I checked with one of the engine converters and he said with that prop it is a good rpm but he uses 20:1 and I have been using 40:1. I will also try the different gas ratios.
I also received my rcxell tach so I will plug it in today. Before I was using an old school TH hand held tach that uses the photoeye compared to counting impulses from the ignition with the rcxell.... will see what happens
