Mechanical Advance vs Locked Advance

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Mechanical Advance vs Locked Advance

Postby Moritz » Fri Feb 24, 2017 12:47 pm

Which is better Mechanical advanced or Locked advance> No Advanced same 32 degrees fixed.

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Re: Mechanical Advance vs Locked Advance

Postby Deano » Fri Feb 24, 2017 4:41 pm

In general, on an airboat or any engine that spends any measureable time at less than WOT locked out timing is NOT the better option of the two. When locked out, it will only be optimal for a small part of the power band at the top end. Even if you start it and runs balls out all the time and then shut it off, there is no advantage whatsoever performance wise to locking it out. Even given that scenario, it would be easier to start, decrease wear and increase longevity to not have it locked out. How many OEMs do you see release a new anything that has fixed timing?

Here is one previous thread, there are many I'm sure:
"The suppression of uncomfortable ideas may be common in religion and politics,
but it is not the path to knowledge; it has no place in the endeavor of science."
- Carl Sagan

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Re: Mechanical Advance vs Locked Advance

Postby SWAMPHUNTER45 » Fri Feb 24, 2017 8:38 pm


Fixed rpm, fixed timing

Varied rpm, varied timing

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Re: Mechanical Advance vs Locked Advance

Postby hdsadey » Fri Feb 24, 2017 8:50 pm

We install FiTech fuel injection systems and they have the ability to control the timing through the computer. That's the only time you should consider locking out the distributor advance. Most aftermarket systems have timing control ability. Pretty neat setup, completely tunable for max advance at any rpm.
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