How fast MTI 40 with 525's ?
#31
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[youtube]http://www.youtube.com/watch?v=RGDNYdVhuZk[/youtube]
MTI running at Smoke On The Water Poker Run
Music sucks on this
I had used somthing more appropriate but You tube changed it
We did not have any engine sounds for this but you can see this boat hauling the mail. Got a little scarry for a minute
MTI running at Smoke On The Water Poker Run
Music sucks on this
I had used somthing more appropriate but You tube changed it
We did not have any engine sounds for this but you can see this boat hauling the mail. Got a little scarry for a minute
#33
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Location: Colts Neck, NJ
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Possibly someone can shed some light on me. When you use a "Prop Slip Calculator" and plug in the following values for calculating THEORETICAL SPEED of a boat running 525EFI and #6 drives:
Gear ratio - 1:50 (highest allowed ratio for racing orgs)
Prop pitch - 40P (maxium size pitch prop allowed)
engine rpm - 5600 rpm (rev limiter set on stock 525EFI)
In theory you get a top speed of 141 mph, with a 7% slip you would see an actual 131 mph. (if the boat was set up right on the money and ran perfect)
I don't understand how all these other " higher mph numbers" come out without changing one or more of the above variables.
I am willing to learn.
Gear ratio - 1:50 (highest allowed ratio for racing orgs)
Prop pitch - 40P (maxium size pitch prop allowed)
engine rpm - 5600 rpm (rev limiter set on stock 525EFI)
In theory you get a top speed of 141 mph, with a 7% slip you would see an actual 131 mph. (if the boat was set up right on the money and ran perfect)
I don't understand how all these other " higher mph numbers" come out without changing one or more of the above variables.
I am willing to learn.
#37
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Join Date: Feb 2005
Location: Gallatin, TN
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Change in gear ratio is the usual culprit. I am pretty sure the ratios are as follows: 1.49:1, 1.35:1, 1.24:1 and 1.15:1 so you can see how it can be changed but as you go up in gears you will lose a lot of the punch. My boat has been 153 with 1.35's but with the 1.49's it's 10-15 mph slower but doesn't take 10 miles to get there.
Possibly someone can shed some light on me. When you use a "Prop Slip Calculator" and plug in the following values for calculating THEORETICAL SPEED of a boat running 525EFI and #6 drives:
Gear ratio - 1:50 (highest allowed ratio for racing orgs)
Prop pitch - 40P (maxium size pitch prop allowed)
engine rpm - 5600 rpm (rev limiter set on stock 525EFI)
In theory you get a top speed of 141 mph, with a 7% slip you would see an actual 131 mph. (if the boat was set up right on the money and ran perfect)
I don't understand how all these other " higher mph numbers" come out without changing one or more of the above variables.
I am willing to learn.
Gear ratio - 1:50 (highest allowed ratio for racing orgs)
Prop pitch - 40P (maxium size pitch prop allowed)
engine rpm - 5600 rpm (rev limiter set on stock 525EFI)
In theory you get a top speed of 141 mph, with a 7% slip you would see an actual 131 mph. (if the boat was set up right on the money and ran perfect)
I don't understand how all these other " higher mph numbers" come out without changing one or more of the above variables.
I am willing to learn.
#39
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