Merc. Rev Limiters

[bgagne]

Does anyone know much about the merc rev limiters. I have a 97 454 mag, carb model and I think that it has a rev limiter from a 7.4L.

The part number on mine is 806959-5 and according to the mercury parts express web site, it should be 806745T-5 for the magnum.

Either the motor has the wrong part or my tach is way off.

[Fish boy]

What does your tach show at WOT?

[bgagne]

4400-4500 with 25p mirage plus. I tried a 23p mirage and it would hit 4500 and if you held it wide open it would seem to start missing and lose RPM (I am not sure how the rev limiters work, but I assume that is what was going on). According to the manual, wot rpm range should be 4600-5000 rpm.