RPM difference between engines

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08-29-2012, 08:46 AM

#11

Knot 4 Me

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Have someone ride in the back with a shop tach and verifiy the readings of both tachs at WOT. I've seen analog tachs match up close to Merc's Vessel View up until the higher RPM range where then one tach will be off significantly from the other but Vessel View shows RPM's to be within 50 or less.

My current tach is the opposite where it shows 800 RPM at idle but an inductive pickup shop tach shows 650 RPM. At higher RPM's the tach is pretty close to the shop tach.

Last edited by Knot 4 Me; 08-29-2012 at 08:49 AM.

08-29-2012, 10:10 AM

#12

endeavour32

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Quote:

Originally Posted by MILD THUNDER

Good deal. What pitch you running now? I'd imagine with those cams, getting the engines to 5300-5400 will be the ticket. The old 420's liked 5200, and those cams are slightly hotter I believe. Either way glad they worked out for you!

I'm running 25 hyromotives

D&K- the engine are fresh- they have 10 hours on them as of today.

08-29-2012, 10:16 AM

#13

MILD THUNDER

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Too bad u didn't live closer, I have a pair of 24 hydros in my basement

08-29-2012, 11:24 AM

#14

endeavour32

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My girlfriend lives in Chicago and is coming up here thursday. I wouldn't mind giving a pair of 24's a run. Thats what I ran last year but I sold them this past winter because I was sure I would need to step up in prop size