Riva, I currently have the RXP-X stage 1. I am looking into getting the upgraded impeller and housing, obviously needing the larger injectors. Is the Riva ECU also required or is the stock ECU capable of handling the difference in fuel delivery etc?

thanks

Also, what kind of boost are you seeing with this upgrade?

Yes, you can run our 50lb injectors with the stock ECU.

Depending upon your mods and the conditions you can expect to see upwards of 13.5psi in boost.

Wou, thats a lot off boost at 8000rpm.
What kind of boost will it make with the Riva ECU-8400-8500rpm. ?

We do not recommend running our Pro-Series ECU in a RXP-X. There is an unexplained event that occurs with some RXP-X's where the rear of the craft suddenly lifts at speeds in excess of 76~77mph.

Ok.. ok that sounds bad, do you have a solotion to the problem? I gues it must to be the new pump when it overstuffs
ill better put the kit on my RXT-X instead then. They dont suffer from this right.?

It's not the pump but the pump inlet tunnel. The RXP-X has the same pump inlet tunnel as the RXT-X/RXT. It's longer.

We have a couple of solutions we have been working on. As soon as we decide on the best one we will release it and our Stage II Kit for the X-boats.

Hi again, I hear there is alreddy a solotion to this problem, maybe you can use it!
A friend told me that the only solution to this problem is to make 1-2 small bypas holes near the rear of the grate thru the hull to the pumptunnel, the kawasaki has a build in system like this to prevent overstuffing!

We've tried that and it doesn't work on every craft. And there are no "built-in" systems like that from any manufacturer. Thank you though.