hi all ;
i have a 2007 sea doo gtx limited with a riva stage one kit installed --i'm hitting 7900 to 8040 rpms with it and is about to have the super charger serviced , i'm going to have either the riva gen 2 or the green wheel installed with the steel washers and ceramic bearing --the question being what size pump impeller should i use ? right now i have the solas concord 14/17r in it -what would be a good choice after the super charger upgrade is done ? -- p.s. after the riva stage one kit was installed i have a problem with cavition from a stand still in little chop -- any ideas ?

You might be able to get away with repitching you 14/17R. Our GEN-2 SC Impeller provides better acceleration. Top speed will be about the same; maybe a little better. Get in touch with Impros. Tell them we referred you!

As for the pump cavitation here are a few things to check:

Impeller Cone. Make sure it's tight against the impeller and is not damaged.

Impeller Liner. If there is any damage you will need to replace it. We offer a Stainless Steel Replacement that is much stronger than the stock plastic liner.

Pump Seal (large o-ring sealing pump to transom plate). They have a habit of getting pinched in a funny way when installing the pump.

Transom Plate where it's sealed to the hull. If any of the silicone is missing or it's loose that will cause cavitation. You will have to remove it and reinstall. Make sure to use 3M's 5200 and the proper alignment tools.

RIVA CREW
Please post and ride responsibly!!!

okay a few changes since my last post --2007 gtx limited now with a greenwheel ,ceramic bearings ,steel washers ,SS wear ring ,oil catch can ,SC blow off valve ,riva stage one kit --with the 14/17r i was hitting 8300+ rpms which suprised me i thought the rpm limiter would keep that from happening --i changed to a concord 14/19 impeller and still hitting 8140+ with one person on it and hitting 8120-8140 with 2 ppl on it --i'm trying to stay between 8000 to 8100 --these rpms are all with a full tank of gas and about 25 lbs in the front storage ---now the question is how much do i repitch the 14/19 to 14/19.5 ? or 14/20 ? i'm really suprised with how well my ski is running its a large heavy ski but running very strong -- with the gps i'm hitting between 69 to 70.3 ---and riva with the cavitation you where right i had to reseal the transom plate i used the 3m 5200 plus i had found the the impeller cone came unscrewed on the shaft --put that back on with a bit of locktite this time

If you're using a stock ECU and seeing over 8,300rpms on the display something is wrong. That's past the rev limiter. On the `07's you can, and should, run at 8,100.

There's more to repitching an impeller than just tweaking the trailing edge. You can actually hurt the performance by tweaking just the trailing edge. Don't get me wrong. I'm not trying discourage you or anyone else from doing your own work. With something like this you can easily end up going backwards and not be able to get back to where you were. A special tool called a pitch gauge should be used to check the angle of the blade all the way around. Again, I have to recommend you contact Impros to repitch your prop.

i was going to send the impeller to have it ballanced and pitched at impros i just was hoping to get a idea how much to have them pitch it --- and what is the diffrence between a 14/19 impeller and a 15/20 impeller ?

i wonder if the riva gang took a vaction ?

Sorry. I was out of town, but it was for work and I did not have Internet access. I'd stick with Impros recommendation for repitching your prop. They'll get you straight.