What rpm levels did you see for each of these props at WEOT and what is your gear ratio?
Also what is your boat package?

Brett

So is one better than the other or does it completely depend on the application? I'm running a P5x and thought about trying a maximus but I need to get my prop shaft height # and speed/rpm..

We sell6 different 5 blade propellers for these application and they are all good. Some are better than others depending on the desired outcome and the price point desired.
9 of 10 times a custom recipe LabFinished Maximus will be the best choice because we build it to your desired specifications. It is also the most expensive. Other stock options can offer great performance ehancements as well.

Brett

Hey Brett,

Kind of a loaded question, however those numbers were all on the same day. The 32P and the 5 blade went WFO about 5500-5600, the 30P I have to back off the gas to avoid the limiter.

I have a 28 Nordic, with extension box, XR and Imco -1 with 1.5 gears.

Originally I saw I had a 1.5" spacer putting drive depth 4-5" below hull, ran a 4 blade 30P. Efi 500 with Vortech (540) Removing the spacer made the 4 blade waaay worse with slip and blow out, but made the 5 blade work well. Just enough slip with the 5 blade it seems, holds in turns, barely cavitates rolling on plane.

I'd like to try a -2 and 1.36 gears, My drive is on borrowed time. The 30P leans the boat over real hard anything above 30 mph. The 30P and the 5 blade chine walk quite a bit about 82.

I'd like to stick with a 4 blade to be easy on the drive, but I'll need to stick the prop down further in the water to make that work.

I'd yard that Extension box off there if I didn't have a bunch of steering non sense to deal with.

Seems like most of the 90+ Nordic guys are liking the 5 blades from what I've learned.

You made me a nice Labbed 24 for my last boat Brett, any thoughts?

This is by far the best handling prop I've had, its a 4 blade 31 that had been balanced and sharpened. No chine walk above 80, felt SOLID. Just wasn't enough prop. This run had the prop depth about 5" w spacer.

http://www.youtube.com/watch?v=QkSqXG7p0CE

I have seen it time and time again where using shorty drives required using 5 blade propellers to make drivability and planing acceptable. Often the speed will follow but not always. Allthough the trend for years has been to riase the drives I can't tell you how many times I've had people space the prop deeper to get the best all around performance. Your testing has shown you that already even though the speeds were less.
Testing a larger pitch 4 blade at deeper depths might be the next move.
As far as 90 plus with 5 blade props is concerned, I'd be curious as to the power that was being used.
The boat will tell you what it likes. You just have be willing to follow its lead.

Brett

More power than mine lol...

I figure I'm roughly 800, maybe a touch less. That 87.1 I saw was on calm water. I'd like to think 90 was touchable in perfect conditions if nothing else just to say I saw it!

I bought the boat with the big drive spacer, it looks kinda ridiculous sitting on the trailer. I know vaguely the boats history, and it's my understanding that the spacer is on there for a reason. Ie, the testing has been done-

So with my 30 Bravo 1's labbed by BBlades running 71 at 5100 with 1.65 gears. Looks like about 19% slip

With my 28 Bravo 1's not labbed running 72 at about 5250 same gears looks to be at 14.9%

Would I gain anything on a 312fastech with a 5 blade labbed by you or would I be better of having my 28's labbed and maybe cupped..

Your 30's are at about 17% slip (29.3 P) This recipe could be revisited and possibly adjusted. It will depend on the rpm level desired as to reducing the slip and gaining speed. Decreasing slip can often mean losing rpm.

The 28's are at a better efficiancy but again the rpm level needs to be concidered. We may be able to increase the 28's rpm and gain a couple mph.

5 blades should be tested and in therory they should not lose much or any top speed maintaining the 70ish mark while gainig cruise speed.

I would need to look into your file to make the best determination.

Brett

To update this... I removed spacer, changed to -2 IMCO with 1.36 gears.

It liked the shorter drive (about 2.5 below bottom of boat), no chine walk with 4 blade and doesn't pull the boat over like it deep running it deeper.

I saw 88 once with a stock 28. (5600 rpm) (85 all the time)
I saw 82 with a 26 Maximus with EXTREME chine walk. Backed out of it, put prop back in the box lol.

5 blades make me nervous with the bite they have, just going in and out of gear the CLUNK hurts!

In this application the Maximus would improve with Labbing specific to the boat.


Brett