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Old 11-02-2006, 08:11 AM
Blue_Heron Blue_Heron is offline
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Join Date: Jan 2006
Location: Gator Country
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Default Re: WOT speed on a '83 20' SF w/200

Quote:
I'm pretty sure the 2.5L Spark Advance acts like a rev limiter and automatically retards the timing once you hit 5800rpm (2.0L/2.4L mercs the spark advace module will retard the timing @ 5600rpm) People will often remove those units and manually set the timing up to 24/25 degrees.


I already disconnected the timing module, now I'm experimenting with max advance. I Already did this on the 150XR4 on my flats skiff and picked up 5 mph top end and had to go up an inch in pitch on the prop to get the revs back below 6000.

I'm still not sure what is a safe max advance for a motor turning under 6K. The guys advancing 25 deg. are running well over that. One mechanic I talked to said 21, another said 23. We'll see.
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