Hello, couple questions here. First, I am running a 21 hp vanguard and have been reading that a 23 hp cam has more lift than the other small block cams but usually just mentions its more lift than the 16, 18 and 20. My question is is the 23 hp cam different than the 21 hp cam? Also, I am using this engine in a modified stock class garden tractor puller wit a 4000rpm limit. I have great power in the light classes but in the 1050lb heavy class my rpm's are dropping to 3200 when I am hooked in and pulling good. What other mods or adjustments can I do to the vanguard to gain a little more HP? Thanks for taking time to read my questions, the pulling world seems to cater to the kohler world only, not much info out there for the vanguard. Thanks!