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dchatagnon
09-04-2005, 05:52 PM
just curious but what is the Max RPM on your 351? my ford 351 goes to 4200/4300 max... (41 Miles/hour)
All is new on it. Wires/Coil/Carb... I have checked with the strobostopic light and it was right up to 10 degrees.

6ballsisall
09-04-2005, 05:59 PM
With the stock prop my 86' MC with the 240hp 351W turned 4700 rpms'. With an Acme 541 on it I could turn 5k on glass water. My motor was a little worked though. GT40 heads, high rise manifold and a hot Mallory ignition.

Your R's seem a little low. Hows' the condition of the points?

Cloaked
09-04-2005, 06:40 PM
I have an '85 that runs about 4400 - 4600 and with the 1:1 tranny, its speed is about 44-45 MPH. I have the Acme 541 prop that fits this setup which is very close to the OEM prop. That serves all of my needs, including barefooting and multiple skiers.

BriEOD
09-04-2005, 07:10 PM
I get about the same as Sporty. I have a stock prop but an aftermarket intake.

Storm861triple
09-06-2005, 12:23 AM
Closer to 4k than what some have mentioned above. The STOCK 351 NON H.O. had a low HP peak. I used to run ~40 mph w/a SS 13x12, 3 blade at about 4200 RPM.

I switched to a SS 13x13 4 blade, and now I run 42-43 mph, at 3900 RPM. Either the new prop is WAY more effeicient at top speed (doubtful) or the engine makes it's HP peak closer to 3900-4000 RPM -much more likely given the cam, intake, and head the stock engine came with...

As a testament to this theory, I'm running as fast as some of you -faster than some even- and I'm at 7000 feet elevation. You're revving past the HP peak.

I say load it down closer to 4k, unless it's got some mods.

-Tom

flyinryn
09-06-2005, 02:34 AM
This is a good question since i got to go out in the boat yesterday and opened her up on some glass's conditions.

With four people in the boat and the current i was around 4800 to 4900.
The gauge was closer the the 5000 mark then it was to the 4800 mark. So you do the math.

This was on a 92 190 with powerslot and stock prop.

Hoff1
09-06-2005, 08:57 AM
I've opened mine open several times this year and the rpm never gets above ~4200. I have the standard 351 with a 1:1. My plugs are in good shape, but I haven't changed the wires or points in the 5 seasons that I've had the boat.

6ballsisall
09-06-2005, 09:10 AM
I've opened mine open several times this year and the rpm never gets above ~4200. I have the standard 351 with a 1:1. My plugs are in good shape, but I haven't changed the wires or points in the 5 seasons that I've had the boat.

I am betting if you change those points out and throw in some new wires you'll get yourself a few hundred r's ;)

Hoff1
09-06-2005, 10:29 AM
My list of winter projects include electronic ignition conversion, which I expect some benefit. Hopefully, I actually complete the list instead of staring at it all winter.

Danimal
09-06-2005, 10:43 AM
4600 @ 44.8 mph (gps calibrated)

But, both speedos stopped working this weekend :mad:

east tx skier
09-06-2005, 11:32 AM
351 HO (with upgrades in signature). 4600 RPM 45.5 mph WOT.