Stock Briggs 23hp with Bandit Airdrives 1:68 drive and Ultra Prop II 60" with 8* pitch blocks. 30mm Nibbi carb with 130 main jet. Deleted governor. Everything else stock. I played with some jets today and settled on the 130 in the Nibbi. I had a max rpm of 4100! super stoked about that. That is a prop speed of 2440rpm with my 1:68 drive and 8* blocks. An online calculator i used shows that to be 35hp at 180 lbs of thrust! Anyway up till about 90% throttle it would max out then past that it would bog down. It did this with every jet i tried and the 130 ran the best through out the throttle range besides the last 10% of max throttle. Do you think i could adjust the needle in or out? Otherwise i think the 130 is the ticket right now. I never would have expected to get these kinds of rpm's stock with a 1:68 ratio.
