70 to 75 mph tritoon: sportmaster or 5.44hd case

**engineermike** · 02-14-2018, 08:59 AM

Just be mindful of the warranty when reflashing.

**Rynobull** · 02-14-2018, 09:13 AM

Gotta pay to play!! :-)

**engineermike** · 02-14-2018, 07:29 PM

Basically with the 400 you get 50 extra horsepower, I believe from the calibration, and the sportmaster lower unit with a reeeeaaally low water pickup. You can flash the 350 for extra power but the lower unit becomes a problem over 80, and with the flash you lose the warranty. I'm not convinced the simon and whipple flashes really get you 450 hp because both engines use knock sensors to maximize ignition advance. If they get you anything it might be only in just the right conditions but you just sacrificed your warranty on a $20-30k motor. I went through the exact same decision struggle and elected to get the 400r for the warranty, lower unit, and of course power (not having to modify it).

**Hayabusajm** · 02-17-2018, 06:54 AM

Originally Posted by engineermike

I'm not convinced the simon and whipple flashes really get you 450 hp. If they get you anything it might be only in just the right conditions.

i'm with you on this, a lot of talk & advertising but no dyno graphs, one would figure that at least Whipple, with acces to their dynos, would produce a graph of proof. Just saying.

**Rynobull** · 02-17-2018, 07:02 AM

Never really looked at that way. With the rep whipple has I just took it for fact! I'm gonna dig around and see if I can find any more info.

**stvman** · 02-18-2018, 07:40 PM

Originally Posted by Rynobull

Never really looked at that way. With the rep whipple has I just took it for fact! I'm gonna dig around and see if I can find any more info.

I have a 24 foot hypertoon with a 250 HO e-tec that runs 70.2 mph, I want to upgrade greatly on the engines, can someone help me with the performance difference between a 400 hr and a turbo-charged Yamaha? I know both motors weigh more than a 505 e-tec but the extra weight wont hurt this pontoon at all, in fact it might help it.
Contact Info: Ronald Alstott. Corydon Indiana. 812-968-4290

**engineermike** · 02-18-2018, 07:48 PM

Isn't the Yamaha a supercharger kit? I don't doubt that the Yamaha can make as much power as the 400r, but for how long and how much tinkering will it take? The 400r is a production engine, designed to handle 400 hp for thousands of hours, and warrantied. The Yamaha is less likely to work perfect from the start and less likely to have the long term reliability. Then, there's the question of the lower unit. There is no fat shaft or hd lower unit available on the Yamaha. I've heard of people adapting sportmasters to them, but the non-hd sportmaster will have a shorter than optimal lifespan behind 400+ hp. The 400r comes with a larger diameter housing than the older sportmaster so they can fit bigger stronger gears. It has the fat output shaft as well.

**Capt.Insane-o** · 02-19-2018, 03:26 AM

Originally Posted by engineermike

I

The 400r is a production engine, designed to handle 400 hp for thousands of hours,

lol

**fasttoons** · 02-19-2018, 05:51 AM

The 60+yo wife of the Playcraft owner setting the single outboard LOTO Shootout record of 78mph for a pontoon. Stepped hull, extended rear center tube ,full interior.

https://www.facebook.com/speedboatma...9348931060649/

**Capt.Insane-o** · 02-19-2018, 07:06 AM

That's the one ^ the triple 300x is the same brand?

**fasttoons** · 02-19-2018, 03:00 PM

Originally Posted by Capt.Insane-o

That's the one ^ the triple 300x is the same brand?

That's a South Bay.

**fasttoons** · 02-19-2018, 03:06 PM

Old photos from three years ago. Check out how extended the rear center pontoon is. Stepped outside pontoons. This is not the same boat. This is a Playcraft Poker Run 25'.

**stvman** · 02-23-2018, 10:09 PM

I have 24 foot hypertoon pontoon with a 250- HO- etec that runs 70.2 mph, if I upgrade to a 400R mercury can somebody estimate what the speed increase might be? Including the ideal proper setup.

Ronnie Alstott,
812-968-4290
Corydon, Indiana

**engineermike** · 02-23-2018, 10:45 PM

Originally Posted by stvman

I have 24 foot hypertoon pontoon with a 250- HO- etec that runs 70.2 mph, if I upgrade to a 400R mercury can somebody estimate what the speed increase might be? Including the ideal proper setup.

Ronnie Alstott,
812-968-4290
Corydon, Indiana

87.......according to http://www.go-fast.com/boat_speed_predictions.htm

**fasttoons** · 02-24-2018, 07:18 AM

Originally Posted by stvman

I have 24 foot hypertoon pontoon with a 250- HO- etec that runs 70.2 mph, if I upgrade to a 400R mercury can somebody estimate what the speed increase might be? Including the ideal proper setup.

Ronnie Alstott,
812-968-4290
Corydon, Indiana

Any photos of the hypertoon? The bottom? As I recall it's two flat wide toons concave shaped-