07-20-2008, 09:01 PM #1
Pulley Kit - List your numbers for the HOTTTT Days
I just got the pulley kit installed and am wondering what numbers others are seeing. I have a bunch of mods, including the R&D Intercooler Upgrade Kit. I think the R&D Intercooler kit helped me maintain my numbers throughout the day. I am somewhat disappointed in the pulley kit. My boost is up to 14, but RPM's were right around 7800 all day with a top speed of 69.0 gps with a half tank. I'm wondering what kind of numbers the rest of you are seeing with your pulley kits. The temp was hot and humid. Water temp was also really warm. Please list your numbers so that I can see if my rpm's are where they should be. I though most people were seeing 71+ with the kit, but that was probably when the temps were cooler. Thanks in advance!
07-20-2008, 10:14 PM #2
With the pulley kit and few mods we have consistently seen 70-72 in cooler weather but when the heat roles in we have seen huge declines in speed. What the key is to learn how to tune the boat for different seasons.
Use your AFR to help tune the boat. If your running the stock prop then 7800 rpms in the heat isn't that far off. Also remember that every boat is different. Ive seen boats that we easily got to hit 73 and others that couldn't get past 70. Also check your compression. Some stock units come out of the box with 145 to 155 psi but others I have seen as low as 125 psi. Those lower psi units have been the ones we see have the most issues with GIO.
From the 20 or so units I have worked on, it has been alarming the differences and the temperament to tunning. Ive also seen huge differences in the bottom of the hulls. Some are Fri hulls and the some are Mon hulls. lol We've had to sand on a few hulls to get then straightened out a bit to get better numbers.
So the answer for me is 70-71 in the dry hot weather, worse when hot and humid and in the cool weather on cool water we have seen 73 often.
Again some boats are just stubborn and wont go over 70. Keep working at it with tunning and ride plate adjustments.
Of coarse this all can be debated but I'm simply sharing my personal findings from working on more then just one boat.
07-21-2008, 07:18 AM #3
Thanks Skip. I'll run the fuel down and get some real speed runs in. I think I should see 70 if I hit 69 with more than a half tank. We shall see.
07-21-2008, 06:18 PM #4
Anybody else have some numbers to share in the heat?
07-22-2008, 08:29 PM #5
I was just in jersey and it was 99 degrees and very humid!
07-25-2008, 04:31 PM #6
I am a stupid @ss! My fuel pressure was set at 60 psi, not the 45 that it should be. I changed it and my speed and rpm's went up. Rpm's averaged 7900-7950. Speed was 70.7 at its max and mid 70.xxx's all day. The temp outside was 85 and very humid. Water temp was close to 80. Rudy's kit gets two thumbs up from me. Very good deal as well! I didn't even do runs with low fuel. I probably won't fill up and do some speed runs tomorrow. The R&D Intercooler upgrade was in full effect as well. My performance didn't drop all day and I was running it hard. 2 and 1/2 hours of riding and no performance loss! Finally, my ski is running like I expected it would with all the things that I have done to it.
07-25-2008, 04:37 PM #7
Very nice! Glad you found out the issue...how's the torque on the ski?
Looks like the ONLY thing missing now are some Sponsons...
07-25-2008, 11:09 PM #8
LOL and you look to be missing the R&D Intake Grate!!! lol
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