Folks I have a question for the experts. Currently I own a 2006 GTX Limited with 21 hours of use, well broken in and confirmed GPS speed of 65.3 mph. I intend to purchase a Riva Stage I kit for this season but was wondering if there are any other parts that I should add which will make a significant speed difference. I really am a casual rider and jumper and do not wrench. I do not want to make any major engine mods so really want to stick to some safe changes. So besides the Stage I kit and clutch washers would a Vortech Supercharger Impeller make and speed difference? If I replaced that and did the Stage I kit is there anything else I would need? I am just looking to try to stay ahead of the Kawasaki Ultra 250 that my buddy has bought. Any help would be appreciated!

You might want to be careful going with a RIVA stage 1 kit and then adding the supercharger impeller. adding the SC impeller without repitching your or upgrading to a steeper impeller in your pump could actually hurt you more than what you would get out of it. with the stage 1 kit, the pump impeller you get w/ it is designed to work together with all the other parts. riva shows about 69 MPH w/ their kit. I'd look at the R&D stage 1 kit, it shows about 71 MPH on their tests, it's almost $1500, but you get more speed and it's still a relitivly east install. i hope whatever you decide to do works great and have fun

This message has been edited. Last edited by: RIVA CREW,

You can request a different impeller than what we recommend for our Stage I Kit if you intend to add the SC Impeller. Which, by the way, is a great addition to the Stage I Kit. Our sales staff is trained well enough to know to make recommendations when upgrading kits.

Okay what speed increase would I see with changing the Impeller and the SC Impeller? Also not familiar with R&D stuff though I will check with my Sea-doo dealers. I do know they are RIVA dealers and have no issues with the RIVA kits.

The SC Impeller won't net you much in top speed gains. It increases boost providing increased acceleration and mid range primarily. This is the reason you need to go with a different pump impeller than what we recommend for our Stage I Kit.

Just a quick note, in case you aren't aware. The stock ECU will compensate for the increased boost maintaining a safe air to fuel ratio. We performed extensive Dyno and water testing to determine this.