So I have a 18' 73 tahiti with a mild(400hp) 455 olds and a place diverter. I can cruise at 27-30mph @ 3k RPM. I really dont feel like building the motor, as I dont want to lose what limited reliability I have with a 455, so I was thinking of building the pump. My goals are more towards cruising at lower RPM than all out top speed, but i admitt, its nice to go fast. With all that said, I am going to get the pump rebuilt, and Id like to add a droop and a ride plate,(the one that does not require any maching) as that seems to be the next step. Any input? Is it worth the coin? Anything else I can do? Also, my pump is a 12JC-A. I plan on sending the bowl to jetboat performance for the conversion to a split bowl. Like I said...any ideas for more efficiency would be greatly appreciated. Thanks for the help.
I have a 20' cole which I modified like you are thinking. My engine is a bone stock 454, which really only puts out 300hp. It has a delta pad. I consider it a nice family cruiser. When I first got the boat it would only do 49 mph and had a porpoise problem at speed. I rebuilt pump. I added a loader which brought me to 54. I added a bolt on ride plate. This solved handling and porpoise problems. It made my boat think it was longer and brought me to 56mph. I then added a drop. This brought me to me to my top speed of 58mph at 4450rpm. With this set up I can cruise at about 27 at 3000rpm. Boat weights about 3000 loaded. I worked for me.
Thanks all for the advice...I think when the season is over, ill make it happen. Ill get a good GPS [email protected] on the last river trip, then ill get the pump worked on, and see what happens...its only money right?