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2 stroke engine @ 55% or 4 stroke at 80%, which is better?

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JayKoit

Well-Known Member
Joined
Jan 17, 2013
Messages
116
Location
Los Angeles, CA
Hi all,

The title pretty much sums up my post, but here's more specifically what I'm pondering:

I read in one of the many 2 stroke vs. 4 stroke debate threads that it's better to run ANY engine at 55% than 75-85%, regardless of 2 stroke or 4 stroke.

I'm interested in doing a budget build of either a Zenith 701 or a Savannah Bingo with either a Simonini Victor 2 (92-110 HP), Hirth 3503 (70 hp and fuel injected), or HKS 700e (60 HP). (Let's assume for a moment that these are the only engines on earth that will fit these two airframes, so we don't stray from this topic into the world of "you should really consider _____ engine instead of these engines for your build..."):)

Both airframes have FWF components for all these engines, so all these options are easily installable as well.

From what I've read and seen on the ICP/Savannah website, the HKS has the weakest performance/climb/cruise, obviously because it's the lowest HP, BUT I also find more pics/videos of the HKS Savannah Bingo online than any other model, so it appears to be the most popular. Makes sense, because this engine gets pretty amazing reviews and is a 4 stroke, which are generally lower maintenance.

BUT, in order to really properly fly either of these two airframes, especially with two people and fuel, 60 HP is pretty low, and you'd pretty much have to run the HKS to the max all the time in order to get even average performance, which brings me back to the top:

Would it be better to get a higher hp two stroke (like the 102-110 hp Simonini) and run it less intensively than the HKS? Even the 70 hp Hirth? It does share the same 1000 hr TBO as the HKS, and I could fly it like a 60 HP engine (except when extra power is needed) and put less strain on it, heck, if I went with the Simonini I could run the 110 HP 2S model at half power and go REALLY easy on that. Would I end up with a more reliable two stroke over the four stroke in this kind of situation?

Would love to hear your thoughts. Thanks!

Jaykoit
 
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