# O-100-- interesting new engine

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##### Well-Known Member
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Why so negative? He is not trying to take your money from the grave! Or he cannot correct or dispute maybe incorrect endless conversations on engine that may or may not make it to home plate. What have we accomplished in life to be remembered by. This is a trophy that we cannot take from him. Keep talking, we only respect him more!

#### Victor Bravo

##### Well-Known Member
Supporting Member
Pete said he calculated 57HP in the configuration that was being test flown... and this was a beta test version using a non-ideal carburetor, a repurposed 4 cylinder magneto, no exhaust or intake tuning, a new intake runner that was nowhere near "dialed in".

A more ideal and tuned carburetor and intake runner, or a port fuel injection system, is likely to be worth a couple of percent in HP and torque.

An electronic ignition system that puts out a stronger spark and allowed the timing to adjust a few degrees depending on RPM, mixture, and engine load should be worth a little something. Not 25HP, but a couple.

Even at low RPM's, a properly designed crossover exhaust will improve the engine output enough to be measured. No it's not Shelby's 'bundle of snakes', but I believe Ross and the other engine builders will agree it is worth something.

Pete balanced the engine very well, with the specific intention to run it at 2900 RPM, which will probably give you a couple of horsepower more than the O-200 stock 2750 rating.

The cam for the O-100 was intended to be a choice of the 85, 90, or O-200 cam cut in half... OR Pete was also intending to offer a newly produced cam (Isky or someone like that) for those who wanted one. So there was a little bit of torque or HP possible using cam selection.

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#### cluttonfred

##### Well-Known Member
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I agree completely that from what I've seen the O-100 project could well have led to a new engine comparable to an A-65 but lighter and actually in current production. I really hope someone takes on the challenge of completing Pete's work and putting the motor into production.

#### Vigilant1

##### Well-Known Member
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A well running, dependable O-100 engine that produces 50 HP at the (O-200s stock RPM limit of) 2750 RPM would be quite an accomplishment, and folks wanting a "pure," nostalgic powerplant will be satisfied with that. It's not an overly conservative goal, either. The "stretch' is already in there.
If the appeal is the use of certified parts, then clearly a bunch of modifications to them, or custom parts from race engine shops, will detract from that. We're definitely getting into 'stone soup" territory. "See that drain plug? It's an OEM part, the only one we can see."
Running it at 3000 RPM with a high CR, etc, while using the stock conrods and pistons--I dunno about that. Is this the "certified reliability" that is part of the appeal of the project?

A fine and all too rare approach in the business of aviation:
"Under promise, over deliver"
That, IMO would be a good way to respect what Pete has done so far and to make it more probable that the next person carrying it forward isn't also facing a pile of unachievable public expectations.
One path is "Jan"s" way, one path is the "Van's" way.

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#### TFF

##### Well-Known Member
I don’t know about A65 replacement. Back to the what character is the horsepower discussion. A65, Lycoming O-145, many VWs, some Rotax, a Yamaha probably fits in, a bone stock Corvair and others are 65 hp but they all have different characteristics and some can’t be interchanged. They are all running different prop sizes to make 65 hp. O-100 would be filed in between somewhere. It’s back to the prop that’s on the front and what you can get to move it. You can get 100 hp out of a O-100. Useless in an airplane, but give me a saw and I will keep cutting the prop down until it gets there. It would just be a noisy fan. Then it would need a gearbox to use the horsepower.

I assume the O-100 when it was at Oshkosh was on the Crackerjack. My impression of the plane was a Legal Eagle without the 103 restriction or a 90% Baby Ace. It was no full size Cub but it was not flimsy. That’s where this engine will live, 300-400lb empty weight who want direct drive. Parasol, single seat motoglider. Maybe a KR1. It’s not going to replace an engine that is taking off a 1320lb plane. If you made a Double Eagle into a single seat plane, it would probably be great, it would probably not be as good as a full VW and two people.

Sweet spot is going to be where prop RPM and size of prop will fly the plane. Some planes will be good candidates and some won’t. Some will be propped for 50 hp and some will be propped for 60. And there won’t be anything else in common except where the engine came from.

#### Dan Thomas

##### Well-Known Member
Except I have never learned to sew any upholstery.
I'm no pro at it, but I can do it if it's simple enough. Don't know that I would tackle a sofa; that's more complex.

I watched my Mom sew a few times, then tackled it. My wife's sewing machine would act up so I'd fool with it, learning some more.

I recently finished making a custom cover for my restored boat. The "universal, trailerable" boat cover from Costco beat itself to death last summer while on the highway. These things have to be tight like a drum, which means they have to fit that particular boat and no other. Lots of work.

I use an old sewing machine from the 1950s or '60s. No plastic. I wish I could afford an industrial machine like the Juki so I could sew heavy stuff too.

#### Vigilant1

##### Well-Known Member
Supporting Member
I agree completely that from what I've seen the O-100 project could well have led to a new engine comparable to an A-65 but lighter and actually in current production.
An A-65 has a displacement that is 170% of the O-100. It makes its 65 rated HP at 2300 RPM. It weighs 171 lbs. It is comparable to an O-100 if "old timey" is the criteria, but I don't see other specs as being very close.

I really hope someone takes on the challenge of completing Pete's work and putting the motor into production.
That would be great.

#### Pops

##### Well-Known Member
Supporting Member
I'm no pro at it, but I can do it if it's simple enough. Don't know that I would tackle a sofa; that's more complex.

I watched my Mom sew a few times, then tackled it. My wife's sewing machine would act up so I'd fool with it, learning some more.

I recently finished making a custom cover for my restored boat. The "universal, trailerable" boat cover from Costco beat itself to death last summer while on the highway. These things have to be tight like a drum, which means they have to fit that particular boat and no other. Lots of work.

I use an old sewing machine from the 1950s or '60s. No plastic. I wish I could afford an industrial machine like the Juki so I could sew heavy stuff too.
My wife and her sisters makes quilts. Wife has a sewing room with all kinds of nice tools for quilting. I can look, but not touch
I bought a cowhide to do the seats for the JMR. Have the foam cut. She doesn't have a HD machine that will do leather. ( has a collection) A man I know in Ohio that is very good says he will do it this winter. Thinking of buying an old industrial machine that will do leather and seeing what I can do. Maybe get good at making scrap.

#### Dan Thomas

##### Well-Known Member
Let's take another look at the C-90/O-200 TCDS:

Look at the similarities of the two engines. Same bore and stroke, same compression ratio, same displacement, of course. Only differences are the redline and the ignition timing. Continental got the supposed extra 10 HP through bumping the redline, a common trick among both aircraft and marine engine manufacturers. The O-200 would need a slightly different carb, too.

Now, that 24°BTDC timing on the O-200 compares poorly with the 26 and 28 on the C-90. That's a TCDS revision, brought about by some cylinders failing under high combustion pressures. Dumbing down the timing lowered the pressures and also cut the HP a bit. The change was forced by an AD, but cylinders having serial numbers higher than the AD specifies can stay at 28°BTDC.

In any case, as I said, higher RPM makes more HP but higher prop speeds don't always mean you get that much more thrust.

The FAA has recently "improved" their AD system to the point that it's a nightmare to find anything.

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#### Dan Thomas

##### Well-Known Member
My wife and her sisters makes quilts. Wife has a sewing room with all kinds of nice tools for quilting. I can look, but not touch
I bought a cowhide to do the seats for the JMR. Have the foam cut. She doesn't have a HD machine that will do leather. ( has a collection) A man I know in Ohio that is very good says he will do it this winter. Thinking of buying an old industrial machine that will do leather and seeing what I can do. Maybe get good at making scrap.
With a bigger machine you can stitch up your own seatbelts and shoulder harnesses, too. I did my own for the International, by making more passes and using polyester thread. That old truck never had seatbelts when new, nor turn signals, nor dual braking system. When I was done it had all that. Authenticity wasn't the primary goal.

#### Pops

##### Well-Known Member
Supporting Member
There is a large difference in the power of the C-200 with the timing between 24 Degrees and 28 degrees BTDC. Can tell by the sound of the engine on take-off and the longer take-off distance.

#### Flyguyeddy

##### Well-Known Member
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The o100 and double eagle would be cool. I always thought a single seat narrow "double eagle" would be cool to have. Basically a larger LEXL with more power and fuel

#### Flyguyeddy

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The o100 and double eagle would be cool. I always thought a single seat narrow "double eagle" would be cool to have. Basically a larger LEXL with more power and fuel
"Super eagle xl" or something

##### Well-Known Member
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One of my reasons I want to see this done is to put it in the Lil Bitts. Pete was gonna use my Lil Bitts as a demo aircraft. Now its on me to figure it out. Pete had a better chance of fitting in it than I do but luckily I have a friend who is an Acro pilot and he is small.

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#### AJLiberatore

##### Well-Known 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.

Anybody else who cannot attest to anything about this engine, but just assumes this engine would vibrate wildly.... please take one step back, proceed to the Duct Tape Table, and use a piece of the tape to cover the opening under your nose.

There are probably several others, but myself, HBA members MM4440, Topaz, and addicted2climbing have put their hand on this engine while it was running at cruise power, and we can all attest that Pete did in fact design a counterweight or two into the crankshaft, and this counterweight did in fact resolve the typical 2 cylinder engine shake that the Franklin and half-VW are known for.

I have zero formal education or experience with these dynamics and forces, but I know for a fact that some-how, some-way... Pete did manage to design that thrash out of this engine. It was a small amount of extra balance weight in the crank, not a ten pound flywheel.

The fact that someone has stepped up to at least try and rescue this engine from fading away into a footnote should make everyone pretty happy.

#### AJLiberatore

##### Well-Known Member
VB,

I did. I met Pete through Pat Panzera, both now gone west, I cherish my memories of them and the moment I will share. I called Pete at a major airshow, that occurs in the heat of summer ;-), and we met up in an area of lighter stuff. So what happened next was one of those fun moments, kinda like skipping a class and never getting in trouble. Pete greeted me warmly, told me to jump up on the trailer the O-100 was mounted on, & looked around to make sure the coast was clear, ;-) and walked me through the sequence, hot, crack the throttle, & Immic he hand propped it. It came alive. It shook a bit at low rpms, but with my hand on the top of the block, she smoothed out after opening her up a bit. You couldn't help but be impressed.

For all the naysayers out there. My current gig is assembling prototypes of inventions, and my respect for homebuilders, & folks in the kit and this engine space is huge. I spent today trying to get a small number of proto's to a client. You may have no idea what small details mean and how they make you grind to reach the finish line. The last 2 weeks and even more so today, we fought for inches for the 1st down.

What Pete did was last few weeks & today on Steriods. G-dSpeed to the 0-100's next custodian, may they take it across the Finish Line.

#### daveklingler

##### Well-Known Member
The Phazer was the engine that sprung to my mind as competition, but builders over on the FB Yamaha page are claiming over $8000 in costs, counting a$3500 PSRU. The Ace redrive might reduce that cost, but I honestly don't know what Ace charges for theirs.

In any case, if the costs are comparable, I'd rather have an O-100. You'd put a fair amount of time into a snomo conversion before you were done. I'd personally feel better about flying behind the O-100.

Larger HP are a different story, but the Phazer, although viable, isn't a panacea.

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#### Victor Bravo

##### Well-Known Member
Supporting Member
What is the firewall forward weight of the Phazer installation with the redrive, cooling system, ignition battery, etc... everything between the engine mount and the propeller ? I see several good and interesting uses for that engine, and would love to have that engine included in our 21st Century Volksplane and other similar 'small cheapskate airplane' discussions.

Likewise, the O-100 will have a very significant number of airplanes that it is "right" for. There are hundreds of different little airplane designs that would be perfect for this engine... just as there are hundreds of designs right for the VW, the Aeromomentum, the Continental/Lycoming, and the aluminum V8.

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#### Bill-Higdon

##### Well-Known Member
What is the firewall forward weight of the Phazer installation with the redrive, cooling system, ignition battery, etc... everything between the engine mount and the propeller ? I see several good and interesting uses for that engine, and would love to have that engine included in our 21st Century Volksplane and other similar 'small cheapskate airplane' discussions.

Likewise, the O-100 will have a very significant number of airplanes that it is "right" for. There are hundreds of different little airplane designs that would be perfect for this engine... just as there are hundreds of designs right for the VW, the Aeromomentum, the Continental/Lycoming, and the aluminum V8.
V.B. I'd suggest watch this deries

#### BJC

##### Well-Known Member
Supporting Member
What is the firewall forward weight of the Phazer installation with the redrive, cooling system, ignition battery, etc... everything between the engine mount and the propeller ?
Just FYI, a 160 HP APEX Yamaha installation, replacing a Sube in a GlaStar:

I got a final weight for my firewall forward. This is everything to run the engine except a battery, and fluids. 215.5 pounds. This is the same configuration the engine I removed was in when I weighed it. It weighed 363 pounds.

BJC