# O-100-- interesting new engine

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#### Bill-Higdon

##### Well-Known Member
V.B. I'd suggest watch this deries

BTW scuttlebut is it's within a few pounds of a liquid cooled 582

##### Well-Known Member
BTW scuttlebut is it's within a few pounds of a liquid cooled 582

I fully agree that with Pete dragging his feet that there are now other options in this HP space. Yet all require a redrive and as VB mentioned many people have O-200/O-300 Jugs lying around and other bits that can be used to build one. Also it seems Yamaha may start selling a 2 cylinder version as well so who knows where all this will go. For me, at the moment if I just get the few engines cases I have built up and everything works out that's a win for me. I don't intend to make any money and fully expect this to be a losing adventure if just the few engines are ever finished. However if in the end this looks viable to make more then I will make a decision then. For now just
trying to honor a departed friend by taking the reigns sort to speak to finish it for him and for his son to see completed.

#### sotaro

##### Well-Known Member
Supporting Member
The video shows the phazer with PSRU, starter, alternator, motor mount, most of it's exhaust, no intake, no electrical harness, nor radiator, unknown if full of oil, (doubt it) or coolant (doubt it). 109 lbs.

For firewall forward I have seen 135 lbs. I think that was wet.

#### Bill-Higdon

##### Well-Known Member
The video shows the phazer with PSRU, starter, alternator, motor mount, most of it's exhaust, no intake, no electrical harness, nor radiator, unknown if full of oil, (doubt it) or coolant (doubt it). 109 lbs.

For firewall forward I have seen 135 lbs. I think that was wet.
135 is what stick in my mind as well, but we all know my mind is a slippery slope

#### Topaz

##### Super Moderator
Staff member
Anybody who was there, and laid their hands personally on the O-100 while it was running, and who can personally attest to the idea that Pete had balanced it correctly and it was as smooth as an O-200... please take one step forward and feel free to discuss the vibration level. ...
I'm late to this discussion, and am still working through the new posts to this thread from this point forward, so forgive me for sort of "necroposting" a discussion from four pages back but...

I can absolutely corroborate VB's experience on this. I was there. I saw the O-100 running and flying on the Crackerjack, helped move the plane out of and back into the hangar, helped hold it while the engine was warmed up, and experienced the entire operation from a distance of an arm's-length.

Any notion that the O-100 was prone to any unusual levels of vibration is absolutely 100% incorrect. It's a very smooth-running engine, even in the prototype form in which I saw it. Pete had made several improvements to the thing after the early flight tests, and I'm sure the final product would've been (and may yet be) a real gem. If Pete had a flaw, it's that he was a bit of a perfectionist in his engineering. I'd have released to production in the form it was in when it flew the day I was there, but Pete wanted only the best before he would put it in the hands of customers. He and I had a couple of discussions about that over various diner booth tables.

#### Topaz

##### Super Moderator
Staff member
Like you said, at cruise power, meaning that the rotational inertia was carrying the compression load
and power pulse load at a rate that the mass of the engine case could not react to with it's inertia....
Try that at idle or under say 1500 rpm.....and as for that tape.......
Simply not true. I've seen and felt the engine run first-hand. It did not shake any more than an O-200 or any other certified aircraft engine that I've experienced, even at idle.

I appreciate that you feel strongly about this but, from first-hand experience, I can tell you that you're not correct in this case.

#### TerryM76

##### Well-Known Member
Supporting Member
Simply not true. I've seen and felt the engine run first-hand. It did not shake any more than an O-200 or any other certified aircraft engine that I've experienced, even at idle.

I appreciate that you feel strongly about this but, from first-hand experience, I can tell you that you're not correct in this case.
I had the same experience when seeing Pete's engine at Copperstate. I got to talk with Pete for a while and I had hands on the airframe when he ran the engine to full power. No noticeable vibration beyond what you would expect from a reciprocating engine powered aircraft and the idle was smooth as well.

Terry

#### mm4440

##### Well-Known Member
Supporting Member
Most obvious & readily available is the Yamaha Phazer (drives already available), but there's also the CanAm V-twins and their Chinese copies (Gaokin). The other sled & watercraft makers make engines that are competitive with the Yamaha.
Engines mentioned are heavier, especially when installed.. The perennial questions: PRSU or direct drive, air or liquid cooling, 2 or 4 stroke, cylinder arrangement and number of cylinders, piston ,rotary or turbine. What is important is power to weight and and power per dollar.

#### mm4440

##### Well-Known Member
Supporting Member
Just FYI, a 160 HP APEX Yamaha installation, replacing a Sube in a GlaStar:

BJC
That is about what an O-200 weighs with 60 (+) more hp. I am a fan of the motorcycle derived engine conversions. Is a typical airplane guy going to be comfortable with an engine turning 7500 or so rpm in cruise?

#### sotaro

##### Well-Known Member
Supporting Member
I think Teal Jenkins, who flies a Yamaha Nytro, three cylinder factory turbo snowmobile engine with a peak of 200 hp, cruises at 6500 rpm. This engine is under development. He posted info on the RV forum. This engine is in an RV-9 I believe. Others (not RV's) are flying the Apex, another Yamaha snowmobile engine, 1 liter, four cylinder, a derivative of the R1 motorcycle engine. Most of those conversions, as noted above, have been in high wing STOL planes.

#### rv7charlie

##### Well-Known Member
Supporting Member
Engines mentioned are heavier, especially when installed..
Really? What does (or will) the O100 weigh, complete, FWF?

#### mm4440

##### Well-Known Member
Supporting Member
Really? What does (or will) the O100 weigh, complete, FWF?
My understanding is it was about 10# heavier than a 1/2 VW with the same electric equipment., and there is room for improvement. It is really hard to get accurate engine weights.

#### rv7charlie

##### Well-Known Member
Supporting Member
Then it would seem to be really hard to make the claim that others are heavier. ;-)

The all up weight of the Phazer has been reported by builders to be 10-15 lbs more than the Rotax 582 that was removed. Is a 1/2 VW as light as a 582?

#### Dan Thomas

##### Well-Known Member
What is important is power to weight and and power per dollar.
Yup, and unfortunately, poor power-to-weight comes cheaply, and good power-to weight is expensive. A builder can use a junkyard Chev 350 V-8, make it direct drive, and get maybe 150 HP at 2800 RPM or so. Real cheap, but terrifically heavy. 550 pounds or more, plus rad and coolant and exhaust and stuff. Easily 600-650 pounds.

Or one can find a good used Lyc O-320, 150 HP at 2700 RPM, that weighs 275 or so, complete. Half the weight of the 350, and every ounce matters in an airplane.

So we don't see junkyard Chev 350s flying, do we? We see Lycomings. A lot of them. The Chevs we see flying are aluminum V-8s, not so cheap, and they have redrives, too, not cheap either.

#### rv7charlie

##### Well-Known Member
Supporting Member
Lyc O-320, 150 HP at 2700 RPM, that weighs 275 or so, complete
If you mean no oil, no exhaust, no carb, no mags, no alternator, no baffles, then *maybe* (if it's been acid dipped to remove some weight).

If you mean 'ready to fly', show me. ;-)
If you say 325-340 lbs, I'll consider it realistic. I agree that 'traditional' is the best path for the vast majority of builders, but we should be realistic about it.

No question that an iron block 350 would be too heavy. An aluminum LS motor, on the other hand, would make more like 200 HP at DD rpm, and could possibly fly at ~400-425 lbs, direct drive. (Not that I'd try that.)

#### mm4440

##### Well-Known Member
Supporting Member
We have drifted far from the subject of a somewhat affordable~60hp four stroke alternative to two stroke flying snowmobile engines for very light aircraft. An LS-3 with a cam change and a few other bolt ons is a 500 hp HP engine that you can de-rate as desired at a bit more total installed weight than a Lyc or Continental 540/550. That is a different story. A friend did an article for Contact many years ago taking a hard look at an iron block sbc 350 as a direct drive airplane engine. The conclusion was you give up a seat or two for much improved affordability.

#### daveklingler

##### Well-Known Member
Also it seems Yamaha may start selling a 2 cylinder version as well so who knows where all this will go.

The Phazer is a fuel-injected, four-stroke twin.

From Marc W's Phazer Build thread elsewhere on HBA:
The engine with the PSRU is about 102 lbs. The engine mount is 5 lbs. but it will gain a little more weight with brackets to hang accessories. I am waiting to get the air cleaner before I weigh the airbox. I haven't weighed the exhaust either. I will do that tomorrow.

Marc got distracted with a Rans S-7 and hasn't finished his Phazer install.

This is the \$3500 Skytrax gearbox made for the Phazer by Teal Jenkins.

There's also a Rotax Type C gearbox adapter available, as well as Ace Aviation's newish belt drive. The Phazer yields a lot of performance for a little more money, but it really is a different engine, philosophically, than the O-100. I think there's room for both.

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