# Industrial engine conversion. *Private* group.

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#### pictsidhe

##### Well-Known Member
I am trying to start a private conversation on industrial engine conversions. It is for the discussion of the use of industrial and similar small engines. I have done this as I am fed up with public threads consistently being dragged off into the weeds by a few people here.
If you are interested in participating, make a request here. Almost all of you would get oked, so don't be shy.

#### pictsidhe

##### Well-Known Member
Hmmm, looks like a max of four people. Mods, is there a way round that?

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#### Hot Wings

##### Grumpy Cynic
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We did similar in the past for a study group dealing with Hiscocks book. Like the Cheshire Cat that group faded away and disappeared altogether with the switch to the new software.

Something like a restricted group would/could be an advantage for several of the threads here that seem to go off on tangents rather than narrow the discussion to develop the core idea.

#### WonderousMountain

##### Well-Known Member
We had a Kohler on our Amish made sawmill that I took to liking. It wouldn't cut out on hard or wet wood, even with wild vibration. Only saw it choke out once, and that was under dad's monitoring.

The Kt 725 actually has a larger bore than stroke, so I thought that replacing the cast crank with a stroker could up the power/weight without undue meddling. Maybe 925cc?, If anyone wants to try that,
I'd like to hear their thoughts.

Displacement (cc)44.2 (725)
Bore in (mm)3.3 (83)
Stroke in (mm)2.6 (67)
Gross Torque ft lbs (Nm) 140.4 (54.8)
Compression Ratio9.1:1
Dry Weight lbs (kg)85 (38.6)
Oil Capacity US qts (L)2 (1.9)

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#### karmarepair

##### Well-Known Member
HBA Supporter
The Kt 725 actually has a larger bore than stroke, so I thought that replacing the cast crank with a stroker could up the power/weight without undue meddling.
Can be done, requires a new crank, rods, and pistons. Start here Kohler Command Engine Parts
The billet crank is about $800, the rods another$200+ and the pistons nearly \$400.

#### Gregory Perkins

##### Well-Known Member
I believe that increasing hp increases heat generated and beyond what heat can be shed the engine just keeps getting hotter and hotter. Sometimes you see things that dont make sense. For me it is the Bandolero racing class Briggs engines which are the small CC V-twin that is being factory built as a race motor and sealed to make sure they are not taken apart and tinkered with. It has been at least 4 or 5 years since I checked into them but those engines with replacement rods and pistons and perhaps other internal mods are/were? raced on racetracks at full throttle and as I recall they last a whole season of races before needing to be rebuilt at the factory. I cannot remember whether they retain the cooling fan or not but I would not expect them to last through 12 or 15 races run full throttle etc. Also there may be a class called Bandito .... Cant remember which uses the Briggs engines. This racing class uses mini cars that are bigger than go-karts. My idea was to use one of these engines for a UL motor but I never got around to it.

#### Vigilant1

##### Well-Known Member
Back on track: If there's a mechanism to discuss the development of small industrial aero engine conversions in a focussed fashion, I'd be interested in participating.

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me too,

#### Hephaestus

##### Well-Known Member
I'd be interested. But my focus is shifting around to a psru for now. Still don't love any of the available options.

#### pilot103

##### Well-Known Member
i am interested as well.

#### Hot Wings

##### Grumpy Cynic
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Back on track: If there's a mechanism to discuss the development small industrial engines in a focussed fashion, I'd be interested in participating.
Groups IO, the replacement for the old Yahoo groups, seems to be off to a pretty slow start but TiPi has set up one for small 4-stroke engines. We could give that a try? We number 22 members with my acceptance into the group.

I started a B+S 810 thread today.

#### pictsidhe

##### Well-Known Member
I have also joined the groups.io group I am giving up on discussing engines here.
Unfortunately, private conversations here seem to be limited to 4 people. If the mods change that, maybe we can chat here instead. Public threads here keep drivelled over.

#### Vigilant1

##### Well-Known Member
I've applied to groups.io for membership, and look forward to the discussion.
I'll still be here. This is a great place. I'm loathe to close any doors due to the present irritant/situation, but I do sympathize with those who have had enough.

#### AIRCAB

##### Well-Known Member
I am trying to start a private conversation on industrial engine conversions. It is for the discussion of the use of industrial and similar small engines. I have done this as I am fed up with public threads consistently being dragged off into the weeds by a few people here.
If you are interested in participating, make a request here. Almost all of you would get oked, so don't be shy.
Start you own email group.

BJC

#### blane.c

##### Well-Known Member
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I would like to be in the group.

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#### WonderousMountain

##### Well-Known Member
Applied,
I will consider doing a stroker in other models if appropriate. Gregory, that's a fair point, but the manner of increase matters. A higher compress and turbo will generate temperature increase rapidly. A longer stroke will only add heat to the half to three quarters inch cylinder section. While increasing higher rpm respiration likely will not increase temperature loads, except of course a friction componant. The same is true of boring the cylinder, except that therein you are more likely to ruin optimum rigidity, possibly effecting ring seal.

#### karmarepair

##### Well-Known Member
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I've applied to groups.io for membership, and look forward to the discussion.
I'll still be here. This is a great place. I'm loathe to close any doors due to the present irritant/situation, but I do sympathize with those who have had enough.
Even the primary irritant in these conversations has a certain merit, in that they seem to have actually flown with the hardware they advocate. I filter them out, generally, but occasionally give their posts a closer look, and have found some interesting ideas.

Another way to control the conversation is to create a project build thread and shut off comments, while encouraging, via a Sticky post right at the start, DM conversations.

I've joined the IO conversation, but like Vigilant1, I'm staying here. But You Do You, and Vaya Con Dios!

#### pictsidhe

##### Well-Known Member
Even the primary irritant in these conversations has a certain merit, in that they seem to have actually flown with the hardware they advocate. I filter them out, generally, but occasionally give their posts a closer look, and have found some interesting ideas.

Another way to control the conversation is to create a project build thread and shut off comments, while encouraging, via a Sticky post right at the start, DM conversations.

I've joined the IO conversation, but like Vigilant1, I'm staying here. But You Do You, and Vaya Con Dios!
No, he hasn't flown any of his ideas. I don't think he has ever run an engine after taking it apart, either.