[Small block guy]

I have a mandrel running a belt fuel pump off of the water pump pulley.

I have a 185mm crank pulley turning a 147mm water pump pulley. Then I run a mandrel off the water pump to my belt drive. The small pulley is on the water pump mandrel and has 25 teeth. The pulley on the pump has 68 teeth.

What percent of crankshaft speed is my pump turning???

Aeromotive recommends the pump to run at 50% crankshaft speed. Which is where I think I am???

Thanks, Matt.

 

[Relentless]

I get 2.097 ratio. If my calculations are correct LMAO.

Ex: 7000 rpm @ crank
water pump would be 8806 Rpm (1.258 ratio)
Fuel pump would be 3337.5 Rpm (2.72 ratio)

 

[quick-silver]

Your a bit lower than 50%

46% assuming no belt slip

 

[roozterdvx]

crank is spinning the water pump at 125.85%

water pump is spinning the fuel pump at 36.76%

fuel pump is at 46.26% of crank speed

 

[Glen_Jones]

I also get 46.27% of crank speed.

 

[Small block guy]

Thanks a bunch folks