GPR Ride Plate Testing

[spud]

Here are the plates that will be tested.

1. Jims Plate, as received, angle measured will not disclose, I will say it isn't 5 degrees

2. speedplate skegless, all surfaces trued, angle set to 5 degrees, speedcoat applied

3. Plate with skegs all surfaces trued angle set to 5 degrees, speed coat applied

I have 3 intake grates

1. 2 bar 1200 wings angled back per a mod that was out 2 years ago

2. R&D 800 grate blueprinted (sanded)

3. R&D 800 grate modified

Should get some meaningfull data

I used a sanding board to make sure all surfaces were flat. Measure frequently with a straight edge. I had to remove .040" from the dished area of the plate to get it trued. That was more than two hours to accomplish. Truing the other surfaces did'nt take near as long.

[ABBOTT]

very cool stuff - let us know!!

[RX951]

definitely Keep us posted !!

[VOODOO]

Yes, this should be interesting.

[spud]

Yeah I'll do it with big Mark. If he has his pump and reduction nozzle ground on the bottom we'll try them on his ski too.

I don't know if my sponson blades will be done, but I am going to test an 87 vs. 85 mm nozzle.

my plan go through the plates leave fastest plate on ski, go through intake grates leave fastest intake grate on ski test nozzles.

That should give me a pretty good idea of what I am going to get out of my 1200 package.

I'm going to hold off on the sponsons since I modified the ski to accept R&D 1300 sponsons.

[Robsauto2]

When ya'll going?

[spud]

Thursday the 25th

[spud]

Just got done packing everything. I'm going to need a pen and a note pad to keep everything straight.

Looking forward to it.

[salty]

Take shims in 10 thousandths increments. It is highly doubtful that you will get spot on first time out the gate. Small moves....

Keep us posted.

[spud]

I've got plenty of shims. The Speed plate has already been shimmed many times and is optimal for the ski, the other skeggedplate matches the speedplate and the Jim's plate is as set up by Jim.


after I get my baselines with the grates and plates I may have some time left for shimming.

[spud]

OK. After a full day of testing here are the results

elevation 236 ft temp 80 degrees my 5?? skegged plate 74.0 @7170 both directions

Jim's plate 85?? 73.4 @7170 both directions I did get 73.9 on this plate a week ago in 75?? weather. I wonder if it needed polishing after each use to maintain optimal performance.

Skegless speed plate 95?? 74 at 7180 one direction and 73.8 @ 7170 the other direction. Seems there was a cool pocket of air on one side of the lake conditions were glass to very slight ripple for these three tests

Later in the day Mark dragged out a Pistonwash special. I had no way to check the angle but that plate was well over 5??. It was already 103?? and the water was chopped up slightly. The ski porpoised quite abit but I was able to get some runs in. It managed to pull 73.2 @ 7170. My ski seemed to want to run @ 7170 rpm's no matter what.

I did try the 87 mm nozzle vs. the 85 mm nozzle. The 87 mm nozzle went 72.6 it was 103?? for this as well. I am of the opinion the 87mm nozzle is 1 mph slower.

The Jim's plate is a good all around plate and probably is the best choice for a ported 1300 or choppy water, this is due to the angle and the sharpness of the skegs. It will probably go on my ported 1300 project ski.

The 5?? skegged plate seemed to work well on my setup. Its the plate that came home on the ski.

I have some more mods I am going to try on my skegged plate. After a lengthy discussion with Mark it seems the two flat areas that have the mount holes should match the angle of the center. I'll measure it and see what it is and let you all know.


Joe's RXP was impressive. It runs in the 72 range, gets there in a hurry. It was a workout for the GPR. As the water got rougher and Joes gas tank got lower and I filled my ski they were about even. Earlier I had a little on top over him. The rougher water speeds would have probably been easier to maintain with the Jim's plate. My ski held on good from the hole, a lot better than I expected.

We had a good day it was good to see Joe and Mark

[RX951]

wOw, thats cool Spud, good information ! Ya'll had a good day !

great numbers too

[JIM'S PERFORMANCE]

hello Spud, Add 40 thousands shims in the front of the plate only. Make sure the plate does not sit below the pump shoe on the sides. And you will see about another .7 mph gain Thank you, Jim

[RX951]

How much fuel (level) did you maintain during testing?

[txgp1300r]

Hey spud..good test...great info....what prop are you running?.....i added the shims to the front only on my jims plate and it seemed to pick up..had to step sponsons after that mod..pefect ski now.......