How much cushion in a P boat?
#1
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How much cushion in a P boat?
As a veteran motorcycle drag racer, when we raced in the sportsman/index classes (similar to P classes) several years back we always built the bikes with some cushion. For example... if we were racing Super Gas, a 9.9 second index, we needed to be able to run that elapsed time at any track, in any conditions anywhere in the country. So we would build the bike to run 9.3 - 9.5 in ideal conditions, then slow the bike down as needed at any givin race track/weather conditions.
So... in P-4 where you need to average 75mph laps, how fast does the boat need to run flat out to be competitive? I'd assume you loose speed in the corners and have to make it up in the straights. What is typical? Where do I need to be to be competitive? Not looking to be a sandbagger... just competitive. Be sides I don't even know what my new boat will run yet. I'm told 70ish, so I'd have some work to do anyway.
Thanks for sharing!
Mark
So... in P-4 where you need to average 75mph laps, how fast does the boat need to run flat out to be competitive? I'd assume you loose speed in the corners and have to make it up in the straights. What is typical? Where do I need to be to be competitive? Not looking to be a sandbagger... just competitive. Be sides I don't even know what my new boat will run yet. I'm told 70ish, so I'd have some work to do anyway.
Thanks for sharing!
Mark
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Re: How much cushion in a P boat?
Your thoughts are in the right direction. Dial the boat in to be at the upper edge of the bracket speeds.
I believe it's all based on prop x gear ratio x rpm calc. Smitty should answer this one for you.
I believe it's all based on prop x gear ratio x rpm calc. Smitty should answer this one for you.
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Re: How much cushion in a P boat?
You need to run 80. We will regulate your speed at 80. So if the boat is capable of going faster, you will only be crashing on your limiter. If the boat is a little slower, a good crew can make up the difference. Smitty
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Re: How much cushion in a P boat?
In my humble opinion, If you are running in a 75mph avg lap speed class, in this case (P-4), your boat should be capable of 80 to 85 mph top speed, conditions permitting. We have found, in calm water races, (ie: Cambridge Md, Camden NJ, St Clair Mi., Washington NC to name a few) that our avg speeds have been very close to our max speeds, and many teams broke out. In that case you would have to adjust your setup (props, drive height, rev limiters) So you do not exceed 75 Mph avg lap speed and keep your top speed under 80mph. In moderate to rough water conditions, we very rarely have anyone breaking out of their repective lap speeds.
hope that helps
hope that helps
Last edited by BRUCE SEROFF; 01-04-2006 at 09:34 AM.
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Re: How much cushion in a P boat?
Thanks for the quick reply.
Do you guys have lap timers/stopwatch or something onboard to keep track of your lap times?
Great info.
Do you guys have lap timers/stopwatch or something onboard to keep track of your lap times?
Great info.
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Re: How much cushion in a P boat?
Originally Posted by Underdog88
Thanks for the quick reply.
Do you guys have lap timers/stopwatch or something onboard to keep track of your lap times?
Great info.
Do you guys have lap timers/stopwatch or something onboard to keep track of your lap times?
Great info.
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Re: How much cushion in a P boat?
Do you guys have lap timers/stopwatch or something onboard to keep track of your lap times?
#9
Re: How much cushion in a P boat?
Originally Posted by ScottB
Some boats do, I tried once but can't seem to stay in boat and look at a stop watch at the same time