Nizpro Supercharger for 250 SHO

[Sooner Steve]

I am going to be purchasing this power upgrade soon. Does anyone have any experience with the Nizpro Supercharger? I run a 2016 FX21 LE

[RyneB]

you better have a strong set of testicles.

[Gundog]

7 minutes ago, RyneB said:

you better have a strong set of testicles.

I didn't know that was a prerequisite for purchasing this item. Is there anything else someone should have before buying this product? Nerves of steel? Eyes of an eagle? A wooden leg?

[RyneB]

knowing how to drive a boat at 85+ mph sure does help.

[junyer357]

May want to check rulebook too if you plan to tourny fish. Most have a 250hp limit. I have seen folks dq'd for having a 250 cover on a 300 and other power upgrades. 

[Sooner Steve]

I dont fish tournaments anymore other than occasionally a big bass tournament on Lake Fork, and it's no problem to fish a  different qualified rig.

[Logan S]

No experience, but very interested to hear the results ...I've got a '17 ZX250, no plans on modifications but it will be awesome to see the potential that's there.  

[TOXIC]

Maybe it's just me but I am a more than a little apprehensive to modding an outboard with todays tight tolerances.  Super chargers, reflashing ECM's, lightening flywheels, etc strikes me as risky.  It just seems like any minute problem whether it be with fuel delivery, filters, injectors, etc., will cause a major failure.  "Pushing" these motors for more performance usually comes at a cost whether it be longevity or durability.  I guess if I had the $$ to drop another motor on if I torched the one on my boat now, it wouldn't be as much of a concern. 

[Way2slow]

I assume you are running the Yamaha 250 since that's what the kit is made for but don't see anything about what kind of boat. 

I don't know much about the Yamaha's so I hope it has a lower unit rated for the speeds you could possibly be running.  Then again, for $13K, the kit may come with a LU.  Life can get real exciting if the lower units blows out at 80+ mph and you learn what a bat turn is at that speed.  If you are not sure what I mean by "blowing out", Lower units can create a large air bubble, the faster you go, the larger the bubble gets until it reach the point to where it can make the LU loose contact with the water.  When that happens, the boat does an abrupt U-turn (known as a bat turn) and more than one person has been ejected from their boat when it does.

I will say you are in for an awakening when you sit behind the wheel of a 450hp boat the will run in the 90's to 100's.

With a stock 225 Ficht on my 20' Javelin has a dry hull weight of 1,600 pounds and it runs in the mid 70's on a good day with gear and two people.   With one of my 325hp loopers on it, it runs in the low to mid 80's with gear and two people.  With a 460hp 3.3 looper, it easily runs in the mid 90's with two people and gear, and that's not doing any special setup other than the same setup I use for the 325hp motor.  Even run the same prop.  The 325, 3.0 motor turns a custom tuned 26" Raker approx. 6,500, to 6,800 rpm the 3.3 460hp motor turns the same prop approx. 8,000 rpm. (The 225 runs a 26" Raker also, but it won't turn that prop).  If I put  the work I put into setting up the 3.0 into one of the 3.3's, it would probably break 100 with normal fishing load and two people.  My dad was the only person that would ever ride in it at top speed anyway.

Understand also, I'm not a stranger to hot rod boats and how to set them up.  My boat's hull has been blue printer and a special texture on it's contact surfaces (What little there is at those speeds), and there has been a lot of work getting the engine height, setback and prop tuned to perfection.

Not sure how much setup work you have into your boat, but getting it dialed in is critical for a fast, good handling boat.  Finding the right set back, since you probably already have a hydraulic jack plate, and unless out of the box props have changed, you can plan on having a few tuned along the way until you get the magic setup.

That's the thing about speed, once you get used to it, you can never go fast enough.  That's why a keep my lead sled and don't want a Bullet or Allison or any of those hydro rockets, you never quit trying to get that extra couple mph out of them.

I just noticed you said you are running a 21' Skeeter.  They say standard hull weight is 2,100, so that's probably enough boat that wakening that motor up with a super charger would make a fun ride and not to over the top scary.  It will be fast, but should not be scary fast.  The couple of Skeeters I've driven were great handling boats and pretty quick hulls.

[WRB]

I have to admit a supercharged 2 stroke is new to me. The Nizpro 450 is for Yamaha 4.3L 250 SHO, doesn't appear to include a racing style lower unit. Can't imagine the increased exhaust pressure going through the prop hub! Interesting bolt on HP system.

Superchargers put lots of force on the powerhead crankshaft, need different shape piston tops etc, etc.

Having raced boat well over 100 mph I don't recommend anyone trying high speeds without a lot of seat time. As noted prop or lower unit failure of any is a big problem.

What most drivers don't realize is the hull becomes a wing at high speeds and the boat wants to kite lifting the bow then the boat goes airborne and blows over. Speed can be addicting but you need to ease into to it.

Tom

PS, the OP noted he runs a 2016 Skeeter FX21 LE, fast hull! 

[Way2slow]

Like I said, don't know a lot about Yamaha's but when mentioned adding a super charger, I've assumed he's doing it to a four stroke. 

As mentioned, 2 strokes are not very receptive to super chargers/turbo chargers.  Several had done a lot of development on supercharging/turbo charging two strokes but, because of the fact they don't have valves to capture the extra boost, performance gains have been hit or miss.  Before Wayne Taylor died, he was doing a lot of development work on trying and was claiming some good success, but since then, and the fact I've been disconnected from the high performance world for a few years, I haven't heard much out of anyone being successful.  I think Dave Bush was doing some development, but not sure of that either.

Again, I have been out of this stuff for a while and there may be a number of them out there, but  I don't think anyone is claiming the big numbers. 

 

Speaking of Dave Bush, it would probably pay you to contact him.  He probably one of the most knowledgeable people on the planet when it comes to make Evinrude's, Merc's and Yamaha's go fast and what works and don't work.http://www.davebushracing.com/products.html

[WRB]

I see Yamaha VMax 250 SHO is availble in a 4.2L four stroke and that must be what the OP has! When you search 2 stroke supercharger NizPro 450 comes up so not sure? The NizPro Supercharger is a roots type not a turbo. 

Tom

[Yamagod]

Buy a Hydro Tec phase 3 kit and save money and get better performance. Especially on a sho. Nizpro is a better kit for the f series motors or bigger saltwater boats.

[mcipinkie]

Just keep your crazy . . . in Oklahoma.  Stay out of Missouri.

[TnRiver46]

10 hours ago, mcipinkie said:

Just keep your crazy . . . in Oklahoma.  Stay out of Missouri.

They make bullet and Allison boats near my house. Crazy runs deep here!!!

[E-rude dude]

Eh 250-350 whatever it takes?