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Lloyd Sumpter
 
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Default 4 stroke produces more "thrust"????

On Tue, 09 Dec 2003 02:33:31 +0000, F330 GT wrote:

So...if you want to play with TC-3 oil, snort oil fumes, sacrifice
fuel mileage, and endure the noise for a superior hole shot, the 27 to
3 vote is probably right on target. You'll be much happier with the 2
stroke.

I don't get it, but different strokes for different folks.....


Everyone in the marine industry and most of its environmental critics are aware
that there are now at least four manufacturers of two-cycle outboards with DFI,
direct fuel injection: systems that put the fuel directly into the combustion
chamber after the intake and exhaust ports close.


Some interesting data. But I'm confused. If the fuel is injected directly
into the combustion chamber (and I assume immediately burned), how does
the crankcase get lubricated? Is there oil in the "fuel" that's injected?
Why?

Now, you say a DFI 2-stroke has better emissions than a 4-stroke. I infer
that you're talking about a carburated 4-stroke - what about a DFI
4-stroke (like most 4-stroke motorbike engines are, I believe)? As long as
a 2-stoke burns oil, I can't see how it will do better, emission-wise,
than a comparable 4-stroke (ie carb-to-carb, DFI-to-DFI, etc).

And, again by experience: I have yet to see a 2-stroke outboard that
doesn't smoke like hell at idle. And I see a lot of outboards at launch
ramps, marinas, etc. Maybe nobody's buying these DFI outboards?

Lloyd Sumpter
"Far Cove" Catalina 36