Berkeley Overhaul Questions

[ScottRankin]

Just tore apart a Berkeley 12JC-A-H on my 455 Olds powered with diverter 22' boat. Its a bit of a rat but its been good to me for 10 yrs until last week. I spun and seized the Thrust bearing and messed up the impeller when the shaft moved forward. My questions so far are impeller specific the impeller has four slots and has the number L2507 with either an R or maybe an A not sure as its hard to read. The boat was capible of going 65mph? before the breakdown but I had been losing speed the last couple of years. I do not care that much about bottom end as we ski behind another boat would like more top end speed if possible. Any reccomendations on impeller size from you experts and a source for the rebuild kit will be a great help. Summer does not last long around upstate NY and jets are very , very rare.
Thanks,
Scott

[SmokinLowriderSS]

A lot of your speed loss may have been from the clearance from impeller to wear ring getting wide, the rebuild will fix that. Was there any increase in WOT RPM's while loosing speed? Also, any damage to the impeller blades will cause cavitation, which will increase RPM and reduce speed. Again, this will be fixed by the new impeller, but can be kept in check with care and a file or dremmel (or a pump shop)
Typically, a smaller impeller, spun faster, will increase top end speed, but personally, I'd hesitate to put a B in a 22' boat as it trades acceleration for speed. I'd prefer to add HP for speed in that boat