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IO-360-M* with Whirlwind 150/151?

chinch

Active Member
I am hoping that someone may be able to confirm whether the combination of a IO-360-M* (M1B, etc) and a Whirlwind 151 3 Blade CSU (http://www.whirlwindaviation.com/series150.php) is an approved combination?

For my -8, I want 180 hp, the smooth cowl that comes with a horizontal induction, and I like what I am reading about the 151 CSU, but I don't even know what I don't know about engines and prop configurations.

The whirlwind aviation site has a callout that says "Restriction: The 151 Series is not recommended for use in O-360 or IO-360 applications unless the engine is equipped with a counterweighted crankshaft."

Does that rule this specific configuration out? I recall the IO-360M does NOT come in a counterweighted crankshaft configuration? If so, what other choices are available that might let me realise the smooth cowl/three blade CSU combination?

This is all very new to me so sorry if I'm asking dumb questions...
 
A1B6

According to my conversations with Whirlwind, yes, that combination should be avoided with the 151.

The 200 hp angle valve io-360-a1b6 is one of several configurations that will meet your needs as it has both horizontal induction and a counterweighted crankshaft. Have a look at this wikipedia entry, it's a great overview of many configurations. You can definitely learn the Lycoming lingo by studying the entry.

The angle valve does have an associated weight penalty with it, and some have reported being unhappy with the nose heaviness in an -8 with that motor; however, the 151 will offset some of the weight gain.
 
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From their web site:

Notes:

:: Requires use of a Jihostroj governor (475 psi relief pressure)
:: Upgrade program available for model 150 owners, call for details.
* Restriction: The 151 Series is not recommended for use in
O-360 or IO-360 applications unless the engine is equipped
with a counterweighted crankshaft.

Additionally, there were some comparisons run a few years ago. The 150 (predecessor to the 151) did not fare nearly as well as the 200RV props.

Bottom line: It looks like the 151 seems to have been designed with the 320 series engines. For the same cost, you can have the 200RV which was designed for that motor and performs better.
 
Prop/engine combo

If you have your heart set on the three bladed prop, and are ok with 180 hp, consider doing what I have done. I have an 0-360 A1G6D off of a Beech Duchess. It is a parallel valve engine and is one of the few 180 hp engines with a counterweighted crankshaft.

Mine does not have the smooth cowl look, because I have changed it to vertical induction (comes with a rear-facing induction which won't work with the motor mount on the RV). If you can find one, you might be able to change one to forward facing induction to keep that smooth cowl look, but I like the "snorkel," myself.

The angle valve engines are mostly 200 hp fuel injection, and are somewhat heavier. At 200 hp, you might be putting a lot of stress on the 151 prop hub, even with the power pulses smoothed out with counterweights. They are great engines, but I prefer the parallel valve engines in this application for their simplicity. Also, remember that any three bladed prop, as a rule, will produce slower speeds than a two-bladed prop.

I like the idea of a counterweighted crankshaft, but I have not yet decided between the 151, the 200RV and the Hartzell. Be careful about what engine you get that it does not have a crankshaft that requires replacement.
 
Chris,

I was in your shoes a year ago. I had my heart set on somehow mating a 180-HP Aerosport IO-360M1B with a Whirlwind 151. I love the look of a three-blade prop, and I was willing to give up a few knots (perhaps) to get it.

But I just couldn't make the switch to a heavy, angle-valve 200 HP engine with a counterweighted crank, nor could I find an easy 180 HP solution that would work with the WW151 (Mike Gray's solution notwithstanding) and also give me the horizontal induction cowl I wanted.

I decided the Whirlwind 200RV was the answer, and I've never looked back. It's a smooth, lightweight prop that will be fast and reliable. Once you get over the emotional attachment to the 3-blade prop, everything will be OK, I promise. I only suffer from a slight twitch every now and again... :D
 
Thanks so much!

I really appreciate the great advice from everyone - thank you so much!

In weighing up the options, my attachment to a 3 blade CSU is an emotional one, not a practical one, and on reflection, I think Buckwynd is right - the lighter 180hp parallel valve with the two blade 200RV will deliver the best result for me. Keep it light, keep the weight out of the nose of the -8, and with a small engine market down under giving me limited options, and being a first time builder, a straight forward solution that doesn't require any new engineering is probably best.

Once again - thanks for all your advice.
 
It's interesting that Whirlwind doesn't have a prop designed for between 200-260hp. All those folks with IO-390/IO-375 engines are just up a creek I guess.
 
MT 3 blade?:rolleyes:

Took the words off of my keyboard !

We have an MT 3 blade on our TMX IO-360 180hp. Flew behind one before I bought, ours has run but not flown yet.

Beautiful prop, very smooth, lighter than metal prop, comes with it's own spinner which saves some time and anguish.

Our 7 should fly soon, next one will be an 8 with same engine prop combo.
 
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