I know there have been tons of threads on setups.
I've looked through many of them and can't find this answer.
I've got a Shockwave 21 skier with a stock carberated 502. I did the full setback, shoe, ride plate, inducer (loader), Droop, and hyd diverter. I had porposing at cruising that went away at wot. I adjusted the ride plate down slowly and got rid of the porposing. I did this a little at a time with washers for now. However, I seemed to have lost about 3-5 mph on gps. Is it possible the ride plate adjustment is affecting top speed? Did I go too far?
Also, I'm told this engine puts out about 415-420 hp. Is the A impeller the one I should be using? I'm reaching about 4700 rpm. I come out of the hole pretty good for heavy boat, but I'd like to go a little faster than the 53 I'm getting now.
Thanks,
J
I would go to an AB impellar or a B impellar, im going throught the same thing. I replacing my A with a AB actually more on the B side, i did the machineing my self on the impellar. My boat is a 22.5 kachina with a 454 mildly built, i m hoping i didnt turn it to much but im going to give it a shot. Your boat shoud be ok with a B with the horse power you have, good luck.
Thanks, do I need any special tools to remove the impeller.
Can anyone recommend a good place online to buy pump stuff?
It is the 12S Dominator by American Turbine.
J
Because your trim adjustment (ride plate) is fixed, you really won't be able to have both top end performance and mid-speed ride quality. You can have one, or the other. This is where a Place Diverter or some other type of adjustable trim control comes in handy.
If you have a good tight pump, which it sounds like you do, just add more power. The pump can handle more HP, you'll just need more HP in the engine to go faster.
You should also contact one of the jet drive "gurus" (there are a couple of very good ones in Cali.) to help you with the setup.
My 2 cents.
SteveM.
you're diverter should handle the porpoising. if it doesn't, it might not be going all the way down.
A Place Diverter will cure your problem but if you play with your shoe type,shoe depth.intake loader, and make sure the bottom has no hook in it. You should get a happy medium. I'd do that before I'd hang a PD on the back. Budlight :idea:
Before cutting down your impeller remember that you "might" get more top end out of it but you will fore surely lose gas milege and ad extra wear and tear on your engine due to the fact that now you will be turning more RPM at crusin speeds. For 2-5 MPH is it worth it?
Before cutting down your impeller remember that you "might" get more top end out of it but you will fore surely lose gas milege and ad extra wear and tear on your engine due to the fact that now you will be turning more RPM at crusin speeds. For 2-5 MPH is it worth it?
I'd have to go along with Filucky on this one. If you intend to use your boat for skiing/wake boarding, or pulling tubes and the like, I wouldn't go any smaller than an AB impeller. I'm assuming that the above would be your primary concern considering the type boat you have. Going to a smaller impeller will almost definitely compromise your ability to pull up skiers etc.
If you want something fast, you'd probably be better off with a different hull.
Steve (Jetmugg) is right about one thing though, if you want a sure fire way to go faster, throw some more ponies into the mix. Even with 750 hp it'd probably still only be in the 70's somewhere due to it's physical size.
Do you have any idea how much the boat weighs in at?
These are just opinions.
Thanks for the advice guys.
The boat is about 2800-3000 lbs.
I was able to plane out with the diverter to stop the cruising speed porposing. However, I felt like I was pushing the bow down so much it wasn't running very efficient. After adjusting the ride plate, it took les down trim to avoid porposing. I'm just wondering if I went too far with the ride plate and if that could affect top speed. I still have a full range of trim to get an efficient plane, I just lost some top speed.
I'm looking to spend a lot of $$$, just get back what I had. I'll try adjusting the ride back half of what I move it originally and see if that helps.
I'm learning with jets, it is play with till it feels good.
Thanks,
J
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