What is your "CI?" Cylinder Index

Eric Stoltz

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ES
I am building a database, and PoA user’s input is required.

So, a very important measurement, albeit under utilized, is the Cylinder Index. The Cylinder Index, (CI for short) is a measure of one's Otto Cycle machines (4 stroke), Clerk and Day cycle (2 stroke), Wankel engines (rotary), Brayton/Juul (6 cycle), and continuous combustion (gas turbine, rocket).

Before we continue, we must pay homage to Joe Soucheray, for giving us such Garage (Hangar) Logic.

The basic CI interpretation is simple: How many reciprocating cylinders does one keep that turns that reciprocating motion into useable rotary work. “Useable,” in this instance, shall always be defined by the very user of the cylinder.

Very easy examples to follow: I am the soul keeper of a Chevy V8 that powers my RV. Therefore, I have a CI of 8. Or: I am the soul keeper of 13 leaf blowers for my noise making business. Therefore, I have a CI of 13. And: I am the soul keeper of a museum of 7 Felix Millet motorcycles, 2 are daily demonstrators, 5 are on display. Therefore, I have a CI of 35.

These simple rules are no longer simple in this modern age of word definitions, concern for the engines that do not provide current work, and a compensation values for non-reciprocating ICE’s. Thus, we must place a few rules to keep the CI trending towards relevance.

To make my DB relevant, some extra simple rules must first be defined.

Rule 1
Keeper: A person who manages, or looks after the cylinders. If the responsibility is shared by other keepers, the CI value must be divided by the number of individuals who are also keepers. Example: My boat charter fleet has 156 cylinders with 5 mechanics including myself. Therefore my CI is 31.2*.

Rule 2
*Well, since we cannot have anything but integers, the .2 must be rounded down to 31, and the spare single CI (1) vanishes and cannot be counted, ever. Fractions will always be rounded down.

Rule (exception) 3
Wankel type engines: These peculiar ICE’s are a special case. Usually two lobes and their associated elliptical cylinder are fused together. A ratio must be used to compensate for the eccentricity of the cylinder, and that ratio is 1:1.2. Therefore, if one has a Mazda with the Wankel engine, the CI value will be 2.4. Again, the integer rule applies here.

Rule (exception) 4
Rocket engines: Since they are an ICE, usually in cylinder form, (and without getting into the Newton formula for a conversion factor for hangar type discussions) the CI will simply be the length of said rocket propulsion system. Ex: My BigBertha Amateur Built solid fuel rocket is 3.5m tall. The engine system is .5 meters long. Therefore, my CI = .5 x (the number of expendable, single use, propulsion systems one is the keeper for + re-useable systems). Yes, this one gets a bit labor intensive.

Rule (exception 5)
Turbo-propeller engines. The layman in the hangar would logically assume that this CI is 1 per engine. However, this is where the exception of equivalent horse power (not torque!) must be assessed. The *rated* HP of the turbo-propeller engine shall be divided by 100 to reveal an equivalency measure for an accurate CI. Example: Draco has a 680 SHP continuous combustion engine. Therefore, it has a CI of 6.8. Again, applying the integer rule, it must be rounded down to 6. This is a much higher value than 1, and is considered a gesture of “good will.” Be thankful for this exception, turbo-prop keepers.

Rule 6
Jet: The number of combustion chambers shall determine the CI without a conversion factor. The 4 combustion chambers shall be: Can, Cannular, Annular, or Double annular. Ex: My wife flies an ME-262, and I am the menchaniker for the 2 on the wings, and the 2 on the hangar floor. My CI is 24. Or: My Premiere 1 has a CI of 4. Sorry, no additive or multiples for “coolness” or “yeahbuts.”

Rule 7
Electric engines (motors) are out right NA.

Common commentary is important for leading the DB inputs. Remember, there are no rules for for currently “non-working” cylinders - only useable. Owner vs. Keeper, an important distinction. Others shall remark on the suitability of another’s CI if warranted, (or not). Under no circumstances shall one’s CI be influenced by another if the accuser's CI is greater than the defendant's, regardless of the veracity of the influence, unless warranted. CI to Vehicle ratio is a value that has no real value, unless it can be valued by others.

The goal of the DB is to determine a logical “awesomeness [term in progress]” value. Where is the cross-over from one level to another? Where is the line between “not enough” and “whoa dude, have you seen a mental health professional about this?” This is the real unknown that needs a definition.


My CI: 37
Truck +8, Jeep +6, RV +8, B24R +4, her car +4, KLX300 +1, RC engines +5, broken weed whacker +1.
 
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Wouldn’t a rocket be an ECE? External combustion engine.
 
I’m confused. Are we talking aviation or any and all?

Never mind. I read the last paragraph I initially thought was a signature.

Now Im confused why you counted the broken weed whacker that seems against your rules m
 
I’m confused. Are we talking aviation or any and all?

Never mind. I read the last paragraph I initially thought was a signature.

Now Im confused why you counted the broken weed whacker that seems against your rules m

FIFY
My CI: 37
Truck +8, Jeep +6, RV +8, B24R +4, her car +4, KLX300 +1, RC engines +5, broken weed whacker +1.
 
31 if i don’t count things like blenders, vacuum cleaners, power drills, ceiling fans, etc.

35 if I can count the 4 cylinders I replaced on my O-360 that were working when removed.
 
Too many rules!
58499170.jpg
 
15. 6 cylinder 370Z, 6 cylinder Honda Oddessy, blower, weed wacker, chainsaw 1 each.

Oh, I forgot the generator. 1 more. Total of 16.
 
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You have gas powered blenders and ceiling fans? Awesome!
Oops. Too many rules indeed. I misread that one. Have to remove one I counted for the golf cart. I think it should count.
 
three V-8 pick-up trucks = 24;
two X 6-cyl Lycomings + 1 X 4-cyl Lycoming = 16
one X 1-cyl aircraft tug = 1
one X 1-cyl Honda quad = 1
one X 1-cyl Stihl weed whacker = 1
one X 1-cyl Stihl chain saw = 1
one x 2-cyl diesel generator = 2
one x 1-cyl Honda pressure washer = 1

I think that's the lot. Total = 47
 
27, pretty lame. But the new house has a super small yard, so I no longer own any gas powered lawn care equipment.
 
I introduced a similar concept (just cylinder count, no turboprop equivalent or multiple rules) to our group of pilot buddies at Oshkosh a few years ago. It has been a running theme since when any of us buy a new vehicle (adds to cylinder count assuming it isn’t a silly Tesla) or upgrades from a piston to a jet (reduces cylinder count).

I am at 36 right now and should be at 44 soon. Some of my friends are in the high double digits. My father is well into triple digits with a bunch of cars and a working ranch with lots of heavy equipment plus ATVs, dirt bikes, snowmobiles, etc...

My total:
3 Porsches: 18
Aston Martin vantage: 8
Range Rover evoque: 4
Cirrus: 6
In process of purchasing Ferrari F355: 8

I own zero gas powered lawn or other equipment that isn’t car or airplane.

Edit: I forgot I have two glow engine powered RCs - helicopter and airplane. So I guess 38 going on 46.
 
One 8 cyl diesel 8
one 8 cyl Mustang
four six cyl vehicles (Jeep, Lexus, Pontiac, and Ford)
One 3 cyl diesel Kubota tractor
two one cyl 4 wheelers
one two cyl Jet ski
one toy hauler with one cyl generator
one one cyl chain saw
two one cyl leaf blower
one 4 cyl airplane

total = 52
 
Hmmm

Two six cylinder cars (Jeep, camper), two four cylinder cars (Miata, Mazda 3), 20
Two four cylinder airplanes, 8
Two paramotors, 2
Two tractors, one lawn mower, three generators, two chainsaws, two leaf blowers, one pressure washer, one snowblower, one weedwhacker, one strange airboat, 14
That's 44 without counting all the R/C engines, there I lose track but at least another 20-30, so I'll say 25 for a total of 69 without carefully counting.
 
Must be a pilot thing. First it was whose scarf was longer, then whose watch was larger, now how big is your CI. Envy entertainment at its best. :popcorn:
 
Plane 4, Willys 6, Car 4, wifes car 6, 2 chainsaws 2, lawn tractor 2, lawn mower 1= personal total of 27.
Volunteer at the maintenance shed at the Huntsville Botanical Gardens...2 guys share the work for 6 trucks, 5 chainsaws/hedgers, 10 leaf blowers, 6 gas powered golf carts, skid steer and track hoe and an 8N. So about 42 additional CI for me.
 
I always heard it as "Piston Index"...does that make a difference?

All I know for sure is that I'm down 24 since I got married.:eek:
 
Truck 6
My car 6
Wifes car 6
Work car 4
Fun car 6
Nannys car 4
Plane 1 1.2
Plane 2 2
Tractor 3
Chainsaw 1
Leaf blower 1
Snow blower 1
Weedwhacker/polesaw 1
Pump 1
Generator 1
Lawnmower 1

= 45.2
 
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Haven’t “we” done this before?
 
20 that includes my dirt bike that has not run n 3 years. Someday I'll get the dirt bike running again.... I' would like to repower the 2 cycle engine in the bike to a 4 stroke.
edit: forget the lawnmower 21...:)
 
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The basic CI interpretation is simple: How many reciprocating cylinders does one keep that turns that reciprocating motion into useable rotary work. “
The cylinder does not do that, The articulating rod does that.
 
Let's see...

Wife's car: 6 (3.5 l V6)
My car: 4, plus an electric motor that doesn't count (2.0l inline 4)
Daughter #1's car: 4 (2.0l inline 4)
Daughter #2's car: 4 (1.5l turbocharged inline 4)
Boat: 2 x 4 (two 1.8l inline 4's)
Waverunner: 4 (1.8l inline 4)
Lawn mower: 1
Edger: 1
Chainsaw: 1

Total: 33

Daughter #2's car and the Waverunner are new arrivals, so new that we don't have possession of them yet.

Anyone wants to fly down to KGVL and go run around the lake, let me know.
 
I think I’m at 75 right now. Losing count though, there are too many.

Edit: just thought of 4 more, bringing the total up to 79 for the moment.
 
Truck 8
Daily driver 8
Airport beater 6
Garage queen 4
Wife’s SUV 6
Boat 8 (2 x 1.1L I4 10,000 RPM screamers)
Lawnmower 1

Or 41 unless I am forgetting something.

Dad may have an edge:
In town:
Truck 8
Daily driver 6
Mom’s car 6
In town mower 1

On the 22 acre weekend place:
Spare truck 8
Tractor 3
Lawn tractor 2
DR brush hog 2
Wood chipper 1
Kawasaki mule 1

Or 38 unless I’m missing some.

I think we used to be tied before he found the 80V kobalt chainsaw and string trimmer. That cut 2 chainsaws and 2 string trimmer cylinders from his inventory, and 1 string trimmer from mine. I had not really expected one more (4 cylinder) car and the boat to offset the land maintenance equipment.
 
Hmmmm . . . . I am the "sole" keeper of the following:

Car . . . . . . .12
Truck . . . . . .6
Her car . . . . 4
Plane . . . . . .4
John Deere .2
Weedeater . 1
Blower . . . . .1
Chainsaws . 2

Cylinder Index = 32

Looking for gas-powered dump golf cart, soon a pleasure boat, so the count will increase.

Don't need snow equipment, and don't want something to move the plane around, that's my exercise program!
 
Oh boy.... Let me see if I can remember everything

Subaru 4
Truck 8
Mustang 8
Mercury 8
Scout 8
Other Scout 8
Tractor 3
Riding mower 2
Push mower 1
Trail mower 1
Weedeater 1
Log splitter 1
4 wheeler 1
Tiller 1
Generator 1
Polaris Snowmobile 2
Arctic cat 2

Do I count the airplanes since I need an A&P to maintain them
That's gonna add an IO-540... 6
and an O-360 4

So if I'm just counting the non-aviation stuff I maintain myself then it's 60
If we add in the airplanes 70
 
Do I count the airplanes since I need an A&P to maintain them
That's gonna add an IO-540... 6
and an O-360 4

So if I'm just counting the non-aviation stuff I maintain myself then it's 60
If we add in the airplanes 70

Of course you count the aeroplanes!! This is not a game. Do not sell yourself short!
 
I think the last time we did it it was spark plug count.
Ah....OK....real trucks don’t have spark plugs anyway.....so that will increase our manliness a bit on the CI. :D
 
Ah....OK....real trucks don’t have spark plugs anyway.....so that will increase our manliness a bit on the CI. :D

Electric trucks are not real trucks. ;)

I know...glow plugs.
 
OP, unless you missed a rule about a spiritual connection, I would suggest you look up the definition of “sole” and “soul”.


-Skip


I am building a database, and PoA user’s input is required.

So, a very important measurement, albeit under utilized, is the Cylinder Index. The Cylinder Index, (CI for short) is a measure of one's Otto Cycle machines (4 stroke), Clerk and Day cycle (2 stroke), Wankel engines (rotary), Brayton/Juul (6 cycle), and continuous combustion (gas turbine, rocket).

Before we continue, we must pay homage to Joe Soucheray, for giving us such Garage (Hangar) Logic.

The basic CI interpretation is simple: How many reciprocating cylinders does one keep that turns that reciprocating motion into useable rotary work. “Useable,” in this instance, shall always be defined by the very user of the cylinder.

Very easy examples to follow: I am the soul keeper of a Chevy V8 that powers my RV. Therefore, I have a CI of 8. Or: I am the soul keeper of 13 leaf blowers for my noise making business. Therefore, I have a CI of 13. And: I am the soul keeper of a museum of 7 Felix Millet motorcycles, 2 are daily demonstrators, 5 are on display. Therefore, I have a CI of 35.

These simple rules are no longer simple in this modern age of word definitions, concern for the engines that do not provide current work, and a compensation values for non-reciprocating ICE’s. Thus, we must place a few rules to keep the CI trending towards relevance.

To make my DB relevant, some extra simple rules must first be defined.

Rule 1
Keeper: A person who manages, or looks after the cylinders. If the responsibility is shared by other keepers, the CI value must be divided by the number of individuals who are also keepers. Example: My boat charter fleet has 156 cylinders with 5 mechanics including myself. Therefore my CI is 31.2*.

Rule 2
*Well, since we cannot have anything but integers, the .2 must be rounded down to 31, and the spare single CI (1) vanishes and cannot be counted, ever. Fractions will always be rounded down.

Rule (exception) 3
Wankel type engines: These peculiar ICE’s are a special case. Usually two lobes and their associated elliptical cylinder are fused together. A ratio must be used to compensate for the eccentricity of the cylinder, and that ratio is 1:1.2. Therefore, if one has a Mazda with the Wankel engine, the CI value will be 2.4. Again, the integer rule applies here.

Rule (exception) 4
Rocket engines: Since they are an ICE, usually in cylinder form, (and without getting into the Newton formula for a conversion factor for hangar type discussions) the CI will simply be the length of said rocket propulsion system. Ex: My BigBertha Amateur Built solid fuel rocket is 3.5m tall. The engine system is .5 meters long. Therefore, my CI = .5 x (the number of expendable, single use, propulsion systems one is the keeper for + re-useable systems). Yes, this one gets a bit labor intensive.

Rule (exception 5)
Turbo-propeller engines. The layman in the hangar would logically assume that this CI is 1 per engine. However, this is where the exception of equivalent horse power (not torque!) must be assessed. The *rated* HP of the turbo-propeller engine shall be divided by 100 to reveal an equivalency measure for an accurate CI. Example: Draco has a 680 SHP continuous combustion engine. Therefore, it has a CI of 6.8. Again, applying the integer rule, it must be rounded down to 6. This is a much higher value than 1, and is considered a gesture of “good will.” Be thankful for this exception, turbo-prop keepers.

Rule 6
Jet: The number of combustion chambers shall determine the CI without a conversion factor. The 4 combustion chambers shall be: Can, Cannular, Annular, or Double annular. Ex: My wife flies an ME-262, and I am the menchaniker for the 2 on the wings, and the 2 on the hangar floor. My CI is 24. Or: My Premiere 1 has a CI of 4. Sorry, no additive or multiples for “coolness” or “yeahbuts.”

Rule 7
Electric engines (motors) are out right NA.

Common commentary is important for leading the DB inputs. Remember, there are no rules for for currently “non-working” cylinders - only useable. Owner vs. Keeper, an important distinction. Others shall remark on the suitability of another’s CI if warranted, (or not). Under no circumstances shall one’s CI be influenced by another if the accuser's CI is greater than the defendant's, regardless of the veracity of the influence, unless warranted. CI to Vehicle ratio is a value that has no real value, unless it can be valued by others.

The goal of the DB is to determine a logical “awesomeness [term in progress]” value. Where is the cross-over from one level to another? Where is the line between “not enough” and “whoa dude, have you seen a mental health professional about this?” This is the real unknown that needs a definition.


My CI: 37
Truck +8, Jeep +6, RV +8, B24R +4, her car +4, KLX300 +1, RC engines +5, broken weed whacker +1.
 
Around 72. I really need to up my game.
 
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