i have owned a jet sled for years,i have heard that if you sharpen the grates on the impeller housing that it cuts the water and shoves a lot more water to the impeller creating more power,well i have done this to mine and hav'nt noticed anything different good or bad.any other jet owners heard of this and what were the results.scott

It probably marginally helps with the efficiency of water flow, but it is a bad idea overall. The negative is that rocks that used to fall away when you turn off the motor now are wedged into the grate. Many happy hours of prying rocks out of the grate with a screwdriver will follow. I know, cause I did it. Never again.

yeah thumper, that reminds me,i have spent some time with the screwdriver prying rocks myself

I had a sprint boat racer tell me to slight radius the edges on the grate. These crazy people will do anyting for better flow. He said DO NOT put a sharp edge on the plates. Sharp edges will have a tendency to give you better chance to cavatate in a turn.

Keeping the burrs off the grates is a good idea, which will improve water flow and keep rocks from sticking so bad. Filing the impeller sharp will do more good than sharpening the grates for improved top preformance.

scott,
You should sharpen both the top and bottom of the grates. Sharpening and shimming the impeller will give you a noticable increase in power.
There is a ton of things you can do to the shoe of the pump to get more performance. I wont get into it here because its too hard to explain. But believe me it helps. Tom Sperb of Toms outboard is the man to talk to.
his # 1-503-653-8744.