Reply With QuoteGet the "race engine", but make sure to install a stainless impeller.
I have a 20' Sleekcraft Tunnel I had a 455 Olds, ran great, family ski boat. Motor blew, I have a choice between 2 motors: 396 motor rated at 350 horse, or a "race motor", 454, est. 600 HP. The catch is, I have the Berkley 12JG and the manual suggests that the max shaft HP is 500. Any thoughts or suggestions? Mike
Get the "race engine", but make sure to install a stainless impeller.
OOPS! JE pump! (cleanout outside of hull )
Mike
Now ,you definately need the bigger engine to get some speed out of that JE pump!
Dude.....The JG is a great pump with a little work. Polish the inside of the bowl, and put a knife edge on the bowl vanes. For 600 horsepower a bronze impeller will do. Get a S.S. impeller if you can swing it. The sleekcraft is a heavy boat so I would recommend an A/B impeller to start with. In case your wondering what that is. It's an A impeller thats cut down but not quite a B. Make sure you replace all the gaskets and wear ring as well. You will also be greatly benefitted with a loader/inducer impeller. The sleekcraft also like to porpoise alittle. You can get rid of this with a place divertor OR a shoe and ride plate. The JG will handle ALOT of horsepower. The book is referring to 500 max hp because you have an aluminum impeller installed which is stock. Aluminum impellers start to weaken under high HP applications and eventually fly apart and when they go I hope your wearing a life jacket. Go with the bigger motor. Jet boats LOVE torque. Horsepower is a secondary issue. Your primary concern is to get your boat moving. JEt pumps need torque to turn them against the water load. Think of it like this....If all you have is a high reving b.b. with low torque than your not gonna like jetboating very much. You should turn in the "hood of 5600-5800 rpm with a good motor and an a/b impeller. Also,if you want to go more rpm, you gain 400 or so rpm on average from an A to a B and so on. I wouldn't go past a B unless you wanna learn how to build big blocks. Let me know if I can help furthur. My first boat was a sleekcraft SST tunnel. Pretty nice boats but they are hard to get right if your not familiar with them. PEACE>
Posting Permissions