Outboard drag boats, why are there no 4-strokes?

[rochelle howell]

Killed my share of turbo 350's and 10 bolt rears doing that crap back in the day!!!! And motor mounts, radiators, fan shrouds, u- joints, etc. etc.

[FMP]

Only to be done with junkyard beaters, big old floaters.

[mach351]

If you want to build a “1000hp” turbo 4 stroke, then you’ll need a custom mid, and a custom gearcase. That chit ain’t easy to do.....just ask CRT. But if you wanted to throw hundreds of thousands of dollars at a special one off super duper turbo azz kicker, then do it. You’ll find you’ll have no one to race. Will it be fast? Sure. Will it kick the tires off a drag? Yep.

[CUDA]

Just do a 5K neutral drop!

Most drag boat hit 6,000 + RPMs in a heartbeat, kind of like a high stall drag auto.

My old 260 stock lake racer boat can beat my 1400 Kaw off the line, but the boat would be just

103 mph in the 1/4 the bike 128mph.

[powerabout]

I did not say 300XS is a race motor. I am stating that the new 4.6 four strokes weigh what a 3 liter two stroke weighs. Sorry I am not buying the logic about the light weight being everything in drag racing. Why are there no two stroke dirt bikes? Dirt bikes are all about acceleration and weight. No two stroke drag motorcycles? The fastest snowmobiles by far are four stroke turbos even in 500' races. The 4 stroke snowmobiles are heavier than the two strokes but the difference in ET and speed is not even close. I get the one speed (no trans) thing also which is why a SC 4 stroke with all the low end torque should really shine vs the two stroke with porting for 11,000 rpm with no low end torque. So again I ask why not a 4 stroke? I think time will change that.

the area under the curve is what is important for drag racing I think and power to 10,000+ does that
Until you get gears I cant see a 4slug doing what a current v6 2 stroke can do unless a vvt blown one can do 10k?
Sled have the clutch so allows the 4s to compete

Do we have 4s chainsaws yet?
Arent Yamaha coming out with some 2 stroke sleds this year?

https://dirtbikemagazine.com/2018-2-...buyers-guide/?

[CUDA]

Stick a Powerglide in.

[eli]

I can not think of any other motor sport where 2 strokes are the norm other than outboard drag boats. Why is that? I know everyone will say 4-strokes are too heavy. However Mercury's new 4.6 liter V8 four stroke weighs the same as the Mercury 3 liter 300XS. A 4.6 liter 4-stroke with a supercharger can easily make 1000hp with only a 250 pound disadvantage at most. Drag 2-strokes make 400-500 hp at best? Seems to me the big torque (aka acceleration) and hp of 4 stroke is what will propel a drag boat even faster/quicker despite the additional weight. Maybe it is the cost to develop or the newness of the 4.6L Merc. A Speedmaster lower on a light boat with a 1000hp could work on a drag boat. I would love to hear thoughts on this.

all four stroke motorcycle engines rev to 11000 rpm and just as quick as a merc drag or quicker so why not on a outboard hyabusa engines rev to the moon all day and back I know it has lots of gears to keep it in power band but with short prop could work

[powerabout]

all four stroke motorcycle engines rev to 11000 rpm and just as quick as a merc drag or quicker so why not on a outboard hyabusa engines rev to the moon all day and back I know it has lots of gears to keep it in power band but with short prop could work

hyabusa v8 was tried as a F1 replacement, with one gear it needs to be towed onto the plane, no area under the graph issue....
https://www.youtube.com/watch?v=L2ZWqI8Xnfs

[Da Bull]

I think the Hyabusa guys went back to the think tank.

[powerabout]

I think the Hyabusa guys went back to the think tank.

and with them all hope a 4s can replace a racing 2s but never say never 10 years and billions got man on the moon
I can see 2 speed gearboxes coming

[carb a rator]

the epa and the bike manufacturers caused the 2 stroke to go away.

I did not say 300XS is a race motor. I am stating that the new 4.6 four strokes weigh what a 3 liter two stroke weighs. Sorry I am not buying the logic about the light weight being everything in drag racing. Why are there no two stroke dirt bikes? Dirt bikes are all about acceleration and weight. No two stroke drag motorcycles? The fastest snowmobiles by far are four stroke turbos even in 500' races. The 4 stroke snowmobiles are heavier than the two strokes but the difference in ET and speed is not even close. I get the one speed (no trans) thing also which is why a SC 4 stroke with all the low end torque should really shine vs the two stroke with porting for 11,000 rpm with no low end torque. So again I ask why not a 4 stroke? I think time will change that.

[slowJEEP]

https://fortnine.ca/en/who-killed-th...ke-motorcycle/

Good read.

[Twisted Liquid]

Something we tried a few years ago on the National circuit. Junior Drag Boats - 12’ long with 30HP Tohatsu 4 strokes. Unfortunately, the program only ran for 1 year.

[Hot Shot Merc]

Brad z There could be a 4 stroke drag races in their own class if they didnt race against the light weight fast 2 strokes everyone keeps comparing to how it would get eaten by the light 2 stroke existing boat/motor packages. Adding the supercharger to the motor and making big power will work but the boats would have to be heavier to get the CG where it needs and the mids would not have to be replaced with lighter new developed ones with tones of money invested like mentioned. Run the stock sporty and mid,add a super charger on a hull that weighs what it takes to balance the CG and there you have it. A 4 stroke 4.6 drag race package/class. No reason why guys couldn't do this if they wanted. But like mentioned earlier nobody showed to attempt a 300XS class so the same would probably happen with this new 4.6 but it could if people would just do it. Yes the speeds and times etc may not be as quick and comparable but that doesn't matter. It would still fun and exciting to watch and drive as a racer. For example at the local roundy round stock car track I enjoy watching the late models and winged sprint cars just as much as the 4 cyl teen age class that run the beginers class or pure stock. Racing is fun to do and watch no matter what the speeds and ET's are. I mean we still love to watch the lower slower classes at all the outboard drag races so why would this as a class of its own be any different? I would do it if I could afford to and there were others that made it a sizable class to have multiple elimination rounds It could happen

[powerabout]

maybe pontoon boats with 4s would be the right class?