2 Stroke is performance King

**Lake X Kid** · 02-11-2023, 05:10 PM

I think my parameter formula puts the 2 Cycle performance above the 4 Stroke.

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**Speed Jr.** · 02-12-2023, 10:01 AM

Yet the stock 4 strokes are going faster, especially on larger boats. I picked up 8 mph going from 2 stroke to 4 stroke. You enjoy your formula, I'll stick to real world results.

**Lake X Kid** · 02-12-2023, 10:38 AM

Originally Posted by Speed Jr.

Yet the stock 4 strokes are going faster, especially on larger boats. I picked up 8 mph going from 2 stroke to 4 stroke. You enjoy your formula, I'll stick to real world results.

Speed when you drive 8 mph less (than wide open throttle) when operating the 4 stroke, are you burning more fuel than the 2 stroke at the same speed?

**Capt j** · 02-12-2023, 03:18 PM

The 4 strokes have a lot more torque than the 2 strokes. Can swing a bigger prop. I have a 300R and it's an animal. That being said, the motor starts and runs like your car, starts instantly, idles nicely, no stink, no noise, jumps on plane etc. The 300R cms 20" is 512lbs without oil, oil adds another 40 lbs to it. Not that a full 2 cycle oil resevoir doesn't add the same. The other thing is the 4 strokes don't grenade and last........

**FMP** · 02-12-2023, 03:51 PM

Originally Posted by Capt j

The 4 strokes have a lot more torque than the 2 strokes. Can swing a bigger prop. I have a 300R and it's an animal. That being said, the motor starts and runs like your car, starts instantly, idles nicely, no stink, no noise, jumps on plane etc. The 300R cms 20" is 512lbs without oil, oil adds another 40 lbs to it. Not that a full 2 cycle oil resevoir doesn't add the same. The other thing is the 4 strokes don't grenade and last........

Not sure about that, first apples to apples HP comparison of true HP and nameplate rating.

I'll build a 175 and stiker it.... Hmmm ... See it's faster

More than one of these threads on the go...

**Speed Jr.** · 02-15-2023, 09:17 PM

Originally Posted by Lake X Kid

Speed when you drive 8 mph less (than wide open throttle) when operating the 4 stroke, are you burning more fuel than the 2 stroke at the same speed?

I'd say they are very comparable. I went from a 3.4L Etec to the 4.6L 300R. They both are VERY close in fuel consumption, but I will say I keep the RPMs lower on the 300R since it throws a MUCH larger prop. I'm running 15-15.25" diameter 32-34" pitch 5 Blade CNC cleavers most of the time. I wouldnt dream of running props this big on the Etec. I have all the fuel data with the 300R since I put a VesselView in. I didn't have that with the Etec. I had a trick 16" Etec with modified EMM with no rev limiter, custom lower unit, etc, and the bone stock 300R feels like it's 100hp more with a monster prop on it. I'm a long time OMC guy, but for a pleasure go fast, I've been converted. Lol.

Jr.

**Capt j** · 02-15-2023, 09:54 PM

Originally Posted by FMP

Not sure about that, first apples to apples HP comparison of true HP and nameplate rating.

I'll build a 175 and stiker it.... Hmmm ... See it's faster

More than one of these threads on the go...

There's a thread on here from Randy at Liberator boats. I put a 300R on a boat that had a 300XS and picked up a lot of torque acceleration, and I forgot how many mph, but was a considerable improvement. Search for the thread. The 4 strokes make so much torque, they prefer having all of the vent holes in props plugged, you could never do that on most boats with a 2 stroke.

**FMP** · 02-15-2023, 11:25 PM

I've seen that but that new 4s isn't what the stickers claim.
No argument the big displacement of a modern multi cam variable time with all the good should make the power. Actually a 4.6 V8 ... with 10 or 11:1 ratio and all the rest would be considerably underated at 300.
They should just sticker the displacement and actual max HP, it would make more sense. Like perhaps the 360APX which is closer to the truth

**FMP** · 02-15-2023, 11:45 PM

Actually the 3.4V6 4S naturally aspirated with a blower would be another way to some fun but then the 4.6 V8 might just keep it simpler.
This with a blower
https://m.youtube.com/watch?v=CVYkMcBRfMg

**pcrussell50** · 05-16-2023, 11:32 AM

Originally Posted by Speed Jr.

I'd say they are very comparable. I went from a 3.4L Etec to the 4.6L 300R.

Jr.

Switching apples to apples, How much power would 4.6l ETEC make? Or how would a 3.4l “300R” compare to a 3.4l ETEC in a race?

I will admit that as your tolerance for weight and displacement goes up, it’s easier to pack in more and more complexity in order to shrink the fundamental physics advantage that two stroke holds over four stroke. With enough weight, displacement and complexity, you can always shrink the advantage that an inherently superior system holds over one that is less so.

===

Also I find it odd that one would open by talking about performance/racing, and then bring in smells to bolster his argument. Have you ever been to a place where car racing takes place? Every engine there is a four stroke and the air is THICK with the smells of high performance combustion. I’m a road racer, but I bet the smells at a drag strip are similar too. And again, they are going to be all four strokes.

-Peter

**Speed Jr.** · 05-16-2023, 08:16 PM

Originally Posted by pcrussell50

Switching apples to apples, How much power would 4.6l ETEC make? Or how would a 3.4l “300R” compare to a 3.4l ETEC in a race?
-Peter

With a due respect, I really don't care about things that don't exist....I've raced in many different forms, nothing is worse than a hypothetical racer....I just commented on my experience with the same hull that I've ran 3 different motors on. That is all.

Jr.

**pcrussell50** · 05-16-2023, 08:36 PM

Larry mate… Unless I’m missing something I don’t know that going faster with a bigger motor proves that the original post was wrong.

In fact, in pro motocross it was known that two strokes are more powerful, so they created a formula that allowed four strokes to be bigger, in order to level the playing field. This is simple physics, mate. Not a conspiracy against four-stroke.

-Peter

**MrG** · 05-25-2023, 12:44 PM

You have to make the 4STK bigger v6V8 only fire 3an 4 times in one revolution So naturally a 2 stk will make more of everything torque and horsepower at the same bore ,stroke and compression being it would fire every cylinder in one revolution !!

**WaterZebra** · 06-02-2023, 08:42 AM

Add this to the 4 stroke song.............Stoker just won the Parker Enduro with a Merc 450R FOUR stroke averaging (Averaging mind you!) 110 MPH. Mod VP hull with safety capsule (added weight over OEM hull). Hypo theories, what if formulas and one off wonders are all BS. The 450R is a PRODUCTION model.

**MrG** · 06-11-2023, 06:45 AM

Biggest question is how long will the engine last In saltwater ??? For the money spent it’s longevity is disheartening any four stroke outboard today made will not outlast a Mercury/ Johnson 2stroke !! A fact with high exhaust temp internal exhaust corrosion is 7 years max ( 600hp v 12 =70k cost you 10k a year) no saltwater Varados running with 1000 plus hrs in salt water use alive today … My own 35 years as a master mech sadly have delivered you need a new mid and powerhead it’s time is up !! On a lighter note pair of opti’s 250hp 3200 hrs still running stron on a customers boat just put your hard earned money Int rebuilding a strong 3.2 Merc or3.3 Evinrude an keep the legacy going just use opti an xd100 oil for environmental regards