bobl

Ray has an ITS box also. I know the midcabin hurts, just don't know how much. Your nose cone has me wondering because you ran better slip than me using my prop. I guess one other variable is tach accuracy. My tach reads 200 RPM high. I get my data from the computer, which should be totally accurate. It's possible that your and/or Ray's tachs are off some which could really effect prop slip calculations.

BTW...Ray, I'm not doubting your speeds. Just trying to get good data.

Bob

raytart

Let's call it 78 1/2.

Bob
If tach error was a factor which is possible, I just want to say that I'm not even tapping the rev limiter. That's why I feel I still need a few Hundred RPM's. Even if I TRY to over trim to get the rpms up, I can hear and feel that I'm overtrimmed and loose speed and the rev limiter doesn't sound off.

Ray

Steve Zuckerman

Bob,
My tach seems to be dead on the Rinda tool #s at all RPMs. I think the Imco lower loads the prop better than the stock XR housing, resulting in lower slip #s.
Regards,
Steve

bobl

So, that verifies your rpm is correct. I may try a nose cone if I end up keeping my boat. Mama wants a 35 so I may be putting it up for sale. If you know anybody looking, I'll sell it as is, any other power, or with no power.

Nordicflame

Ray,
Did you notice a substantial drop in mid range and low end punch when you changed the gearing.
From my experience it has always been a noticable drop off but didn't change much on top.
Usually the only reason for a gear change is to stay away from the inefficient pitch props (32 and over)

That's a very good running package you have going regardless!!

I can tap the 80 mark at sea level but it takes me two motors LOL

Dave

raytart

Dave,

There is a drop in midrange punch, No question about it. Is it substantial? Somewhat. But I'm willing to make that sacrifice. If the prop is somewhere near where it should be (and I'm close) the accelleration is acceptable. I would really like to get my hands on a 25 pitch P5X and see how that performs. The guys here swear by them. I'm going to send my 26 B1 back for fine tuning next week when I'm away on vaction. I don't want to do it now because I'll be boatless for a week. I'll update my results after I have the prop fine tuned.


Ray

PS: I see you have a 35. Nice Boat. I had the pleasure of being a passenger in a poker run aboard Sick Nordics 35 with 525's.

raytart

They say a picture is worth a thousand words

raytart

But now I'm hitting the rev limiter. I think I'll send the prop back to the shop to slow it down 100 rpm by adding a tiny bit of cupping. That may get me to 82. Or should I leave it alone? I'll have to sleep on this.

PS: I just want to give credit when credit is due...

Tri-State Performance Marine (Paul) Thank you for your Expert Hi-Perf input on my mods. I told you what I wanted and you came through. Thanks again.
Ray

TSPM

Thanks Ray

Glad we hit the target......I will let you know about the final prop tweak early this week.

Paul

raytart

Slip went up substaintially

I'm at 16% slip (1.36 @ 5300+ rpm @ 81 mph.