Thought I'd play with fuel pressures on the dyno at our dyno day yesterday.
230cc hybrids, custom fuel system with 5/8" supply from tank to heads, 1/2 regulated return.
TW Extreme tunes.
4 consecutive runs, made changes as follows:
1) Stock SD
electric pump at 50 psi
2) A-1000 pump at 50 psi
3) A-1000 @ 65 psi
4) A-1000 @ 75 psi
1) was a base line. Same spotter watched all 4 runs. He said the pressure only dropped 1 to 2 psi
max during any of the runs with wither pump. SD
pump, I thought, did pretty well, not to loose pressure at all (basically).
2) Picked up 2 hp and almost 30 ftlb.
3) Picked up another 2 hp and 15 ftlb.
4) Dropped 2 hp, picked up 2 ftlb.
What's interesting to me is the increase in torque, and the graph shows the power coming in quicker for each pressure change, by about 100 rpm. Not much difference in power between 75 and 65psi, but the pump sure strains more.
I just wanted to see for myself if 65psi gets more power than 50 psi
Thought I'd share for those curious as well.