Fastest SOB hull???

[Greg G]

CASE STUDIES - NIZPRO MARINE

In 2008 Yamaha released their brand new Offshore and Super High Output series of outboard engines and dubbed them the "Game Changer". The US market instantly embraced the new Yamaha 6 Cylinder 4.2L Marine Outboard engines with many applications even running two outboards to maximise their performance potential. This triggered a new development program at Nizpro Marine with the goal to produce the most powerful 6 cylinder marine outboard on the planet, with less weight, drag through water and no additional service costs.

Nizpro Marine Director Simon Gishus approached Harrop Engineering and shared his idea to create a positive displacement Supercharger to suit the Yamaha V6. Simon recognised Harrop as the perfect partner for the project, given our rich history in designing and manufacturing TVS Supercharger systems for OEMs globally like Toyota, Lotus and Ford and our emphasis on quality control at our Melbourne based ISO9001 Certified manufacturing facility.

After many months spent analysing the complex packaging requirements and rotating group suitability for the application, a TVS1900 Supercharger Kit was cast and prototype parts manufactured to begin comprehensive testing. The heart of the Supercharger is an Eaton R1900 rotating group which is packaged within the Supercharger manifold featuring twin water to air charge intercooler cores. The Supercharger is driven by an 8PK drive belt and auto tensioner and only adds 55lbs to existing F and VMAX series engines. A key design requirement was for the Supercharger to fit under the factory cowl, a challenging task due to the limited packaging space left by the OEM but achieved with the use of a 105mm spacer. The Supercharger Kit was launched at SEMA 2017 on the Harrop and Eaton booths, winning a Global Media Award in the New Product Showcase for Best New Performance Product. Harrop is proud to be the production partner for Nizpro Marine.

[bouyhead]

Why was the Yamaha platform chosen over other outboard manufacturers? Asking for a friend...

[Greg G]

Take some of the jolt out of your SOB with a hydraulic seat base

[David]

And a Tuff 21 with 300R V8 power

Hopefully the owner takes the time to figure out how to prop it for top end. My impression is that the V8s need different props than the older two strokes

[WavetoWave]

I believe the Nizpro flash is 330 HP? About the same as a stock 300R (328 HP). The bigger Allison ProSport with a 300R is getting 108 MPH, whereas the XB2002 with the Yam Niz 330 is doing 102 MPH. Setup is critical but shows what a beast the 300R is too.

The XB in the pic is riding pretty bow high, makes me think it doesn't have the lip.

[WavetoWave]

The Checkmate Pulsare, not on the list, but has a deeper deadrise than the Lab, Nordic etc and is faster. All nice boats. The 21 Pulsare is underrated though. It's fast and handles really well.

[David]

102 with 330 HP in an XB2002 - only?

I believe the Nizpro flash is 330 HP? About the same as a stock 300R (328 HP). The bigger Allison ProSport with a 300R is getting 108 MPH, whereas the XB2002 with the Yam Niz 330 is doing 102 MPH. Setup is critical but shows what a beast the 300R is too.

The XB in the pic is riding pretty bow high, makes me think it doesn't have the lip.

[WavetoWave]

102 with 330 HP in an XB2002 - only?

Ya, exactly. I think that boat has the lip removed, slowing it down. Or might not be set up 100%.

[RBT]

This will set a lot of people off, but the Allison bottom philosophy is 30 plus years old. I doesn’t seem to be effective in this day. Most certainly with modern power gearcases and props.

[WavetoWave]

This will set a lot of people off, but the Allison bottom philosophy is 30 plus years old. I doesn’t seem to be effective in this day. Most certainly with modern power gearcases and props.

Can't think of any that are better. All the fastest designs are copies or inspired by them so that they're almost indistinguishable. The small Allison's are just too light for heavy engines, the bottoms are peerless.

The prosport 21 is a heavy full on fishing boat and roasts all the other boats on here, except for the Tuff 24, which runs about the same.

The SOBs are slow because there an old design and aren't aerodynamic.

The grand sport does 82 with a 150 four stroke.

[RBT]

I can’t think of another manufacturer that copies or copied the Allison bottom philosophy. And those that tried found themselves on the wrong side of legal council.
Firstly the Tuff has sooooo much more going on with the bottom. I will not discuss what or how but it is not as simple as aerodynamics. Shapes, concave convex tapers etc that are so subtle but in the right places and in the right combinations can add tremendous speed and stability. Using a lip to crate lift works better at low speeds (150hp) but then causes some interesting hydrodynamic phenomena as velocity increases. Consider that psi on your running surface is velocity squared times .0142. The trajectory of this is critical

[WavetoWave]

There's a lot more going on with the Allison bottoms than just the lip. Probably why they hold all those speed records?

Every performance pad V hull has some inspiration from Allison; notch, convex pad etc. Nevermind the monocoque construction.

They don't make sport boats anymore but to suggest the Allison bottoms aren't fast or didn't inspire designs we see now is not accurate.

The 21 bass boat is close to 110 MPH with a 300R. The ultra light Tuff 24 build is about the same right? Which is amazing, I love it.

And yes, aerodynamics are critical at those speeds. The 116 MPH XB 2002 had a lip. Lots of SS and XR running 115+ with a lip.

[RBT]

Critical point on the above comments that is omitted is the fact the fast Allison’s are with 2.4/5 power. Don’t get me wrong I love the Allison’s I grew up watching Owen Boris test and set records. No other performance hull I know has pencil roll for lift.
Side note, Tuff 24 at 110 out of the box in hot humid weather and no dial in time in an almost 25’ deep vee offshore boat that I would venture weighs more than a 21 Allison going 8mph faster is a quantum leap.
Light 24 with a 300xs at 118 (800 lb ish bare shell)
28 with an 860 going 137 (no man’s land)
34 with 1350 going (you won’t believe it)
point is they are currently on top of the game

add, my all time favourite boats are the velocity 22 and the Allison xr2002

[Tomanytoys]

The reason that XB02 is running nose high is because someone bolted a fridge on the back.
That hull was NOT designed for that much weight hanging off the back.

[WavetoWave]

Critical point on the above comments that is omitted is the fact the fast Allison’s are with 2.4/5 power. Don’t get me wrong I love the Allison’s I grew up watching Owen Boris test and set records. No other performance hull I know has pencil roll for lift.
Side note, Tuff 24 at 110 out of the box in hot humid weather and no dial in time in an almost 25’ deep vee offshore boat that I would venture weighs more than a 21 Allison going 8mph faster is a quantum leap.
Light 24 with a 300xs at 118 (800 lb ish bare shell)
28 with an 860 going 137 (no man’s land)
34 with 1350 going (you won’t believe it)
point is they are currently on top of the game

Ya, the Allison's are amazing. A full dress fishing boat,(1,300 lbs dry) heavier than the Tuff going just as fast is incredible. That Tuff 300R was built Ulta light. Great performance too.

From Scott Gilmore
"Originally posted by Scott Gilmore
Randy Pierson has a full interior XR2002 that was radared @ 129 last summer . I've talked with him since then & he tells me he's gotten the same boat to run 133mph (I believe him). I've never heard of any other Allison with top end numbers higher. I sure wish someone else would try for bigger numbers. I do know this , if a full interior, old technology, XR2002 can run 130 there's GOT to be more !! Scott


OLD TECHNOLOGY? Give me a break!!"