Thread: 69.6 without Riva ride plate
09-23-2007, 03:33 AM #1
69.6 without Riva ride plate
Hi guys I can not tell you how importaint it is to get more air to this motor. I took my Ultra back to stock with both water boxes and and stock air box and stock prop, all I could gps was 66.5 even with the other air mods in place, so I went back to shore and put my ski on the trailer and switched it back to the R rated air intake. I did not buy the whole system just the venturie for 54.00 and got the rest local pep boys and local hose shop total 95.00 in air system. Hour later put my ski back on the water and gpsed 68.8 good 2.3 mph faster. Air temp 95 water temp 87. In my pics you can see my air mods that include flowrights under the glove box and opening up the vent in the air scoop all the way through. If you have a buddy with an RXP that has put on a through hull exhaust you can use one of the hoses that is removed from his boat that is shaped just like the one from riva for our ski that is 189.00 to get rid of the second water box. It was good for about .4 top and better acceration and the best part free. You will have to cut the rear pipe just like riva to make it fit. I will post a pic later of this. I also put on a reworked stock prop from Impros, I turned better rpm and it was faster on top.4 but low end did not hit as hard. Now we are at 69.6 so I went back home and rmoved the center bar on intake and all excess silicon from scoop area and polished it all up and now stand at 69.9. I did have on the 2 degree wege for all testing. I am trying to get all I can before I put on the Riva ride plate. I will be at the World Finals at Lake Havasu to get all the hop ups I can for a grand or so. I hear they give good discounts there. Well when I get a chance I will post more and I hope this helps. Thanks Shawn
09-23-2007, 06:50 AM #2
09-23-2007, 10:14 AM #3
Good Job Shawn!
I like the custom touches you've done too.
Can we see more of your ram air mod?
Did you take out the pump holder like i did to polish out?
09-23-2007, 04:50 PM #4
09-23-2007, 06:44 PM #5
Pump Holder, some peeps call it a shoe.
Here's mine after I removed, smoothed, and powdercoated.
09-23-2007, 11:16 PM #6
09-24-2007, 12:24 PM #7
With the Riva ride plate, you should really be flying.
You are exactly right about fresh air.This thing craves it. The more you get inside the hull, the faster it will go. One tip, extend your homemade intake toward the front and you'll get more and cooler air into the air horn.
Removing the rear vent hoses and fittings will also help.
09-26-2007, 03:27 PM #8
09-27-2007, 01:58 AM #9
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