All I can say is WOW !! The B5 in my RC8B preformed outstanding this weekend in the 15th Annual Lone Star Classic in Garland Tx. Did not get a chance to make some good fuel miliage runs do to me just getting this motor last week and very little practice but I did manage to qualify 7th in the A for Sportsman Buggy but broke an upper turnbuckle around the 35-37 min mark of a 45 min. main. I believe it will go around 9min with a the JP3 pipe and a 7.5 rest. This motor has tons of low end!! I allready placed another order for a B5 for a back up!!!!