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IO 340, Anyone using one?

FLEXCopMNPD

Member
I read a really cool article about a carbon cub that had one and the specs looked good. Putting out 180hp and weighing 50lbs less than an IO360 putting out the same power.

Is anyone using a 340? And if you are, how is it?
 
I thought long and hard about putting an O-340 in my -9 but when I looked at the price and weight, I elected to go with an O-360 for less money and only 12 pounds more.

Actually, my O-360 might only be six pounds more as I went with ECi's tapered cylinders which saves a pound and a half per cylinder.

Add to that dual electronic ignition (P-mags), which is supposed to add around 6% more power, and we are looking at a bit over 190 hp for less money.

Bolt on a composite prop and you are lighter than an O-320 with a fixed pitch metal prop.
 
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I think the IO-340 looks very attractive if you're chasing a compromise between power and weight with a FP propellor and I liked the idea for my RV-8 for a while. However, if you add fuel economy and a CSU into the picture, the biggest engine you can fit - without affecting weight adversely - is the solution, IMO. My current thinking for my RV-8 is an IO-375 and a WW 200RV.

The fuel consumption benefit over a smaller engine comes from the following three things:

- slower engine speed for the same power yielding lower friction losses
- more power available at higher altitudes giving more TAS advantage
- better combustion chamber surface/volume ratio giving a thermal efficiency advantage.

Just my thoughts - a snip at only 1p! :D

A
 
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