Stroker kits

Is there a reason something like this isn't available to certificated aircraft.

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Yes, I am new to the aviation community / lifestyle.

Don't own any type of aircraft, nor do I have a pilots license / certification.

If non-TSO avionics can be installed in certificated aircraft, depending on how the IA reads the 14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

and FAA Order 8300.16A APPENDIX A. Definitions (10) Meet Minimum Technical Standard Order (TSO) Established Standards.

I did find this:
https://www.ecfr.gov/cgi-bin/text-i...mc=true&node=pt14.1.33&rgn=div5#se14.1.33_115 (it is possible I am confusing the word "conform" with the word "meet".)

I also found this:
https://www.ecfr.gov/cgi-bin/text-i...d&mc=true&node=pt14.1.33&rgn=div5#sp14.1.33.d

If some aircraft are able to have aftermarket turbo systems installed, then why not can something like above be installed.



 
If some aircraft are able to have aftermarket turbo systems installed, then why not can something like above be installed.

An aftermarket turbo system would likely have a supplemental type certificate (STC) as part of the package in order to install it on a type certified airplane such as a Piper or Cessna.

An STC would also be required to make alterations to an engine such as you’re asking about. Since getting an STC for something like this is a costly endeavor, it is unlikely it will be pursued unless there is a strong demand for the modification. This product does not strike me as a likely candidate for someone to pursue an STC.
 
Yes, I am new to the aviation community / lifestyle.

Don't own any type of aircraft, nor do I have a pilots license / certification.

If non-TSO avionics can be installed in certificated aircraft, depending on how the IA reads the 14 CFR 91 Subpart C— Equipment, Instrument, and Certificate Requirements.

and FAA Order 8300.16A APPENDIX A. Definitions (10) Meet Minimum Technical Standard Order (TSO) Established Standards.

I did find this:
https://www.ecfr.gov/cgi-bin/text-i...mc=true&node=pt14.1.33&rgn=div5#se14.1.33_115 (it is possible I am confusing the word "conform" with the word "meet".)

I also found this:
https://www.ecfr.gov/cgi-bin/text-i...d&mc=true&node=pt14.1.33&rgn=div5#sp14.1.33.d

If some aircraft are able to have aftermarket turbo systems installed, then why not can something like above be installed.

My apologies, I thought the torrent of memes would give it away. It was an in-jest way of highlighting the fact your question is rhetorical to many of us who have seen the sausage get suggested and rejected a time or two.

Basically the answer to your question is that the bigger asks in your wish list are straight up riddled with BS barriers an aviation neophyte or pedestrian would immediately consider obtuse. And they'd be right, but they'd also be tilting at the windmills by coming on here to describe the water. There'll be plenty of posts coming along to describe this sclerotic dynamic to you in more detail; I'm no longer interested in re-litigating that dead-end topic.

Wrt the smaller asks in your list, those are ultimately beholden to the unspoken inconsistency of a system that requires the seeking of an agreeable gatekeeper to lend his signature to ya, and all the machinations involved in placating and cultivating that unicorn once you find it.

So, do yourself a favor and just take the advice of post #6 from the get go. Good luck!
 
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I have flown a few of experimental engines with higher than standard compression ratios. What I have found in the ones I have flown is that the cylinders tend to run hot, it is difficult to keep the CHT’s below 400 with the few I have flown. I am sure there are some things that could be done with cowlings and baffling the might counter act this, but it hadn’t been done or was not very effective in the planes I have flown. That combined with additional pressures in the cylinder, I suspect the biggest problem with these upgrades is it likely reduces the life of the cylinder.

Brian
 
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My IO-390 is 10-1. Balanced, ported, polished, electronic ignition, state of the art injection, cold air sump….. CHTs are mid 300s. Oil temp runs about 200°. Smile factor is off the chart. I don’t want to go back!!!

I have three friends with ACE 409s in similar Cubs as mine. Two are running EFI/EI with 9-1 and the other has the same mechanical FI and Pmags as mine and 10-1.The two with EFI had to add louver fronts to restrict airflow because their CHTs are too cool when cruising LOP. No joke. None has oil temp problems, either. Very cool engines, pardon the pun. ACE had a few really interesting engines going but the company lost momentum and Kevin Eldredge went to Lancair. They used monolithic cast cylinders. Yes, barrel and head cast in one piece. So far the ones I know are holding up just fine.

230hp isn’t hard to get. My engine should easily exceed that but I didn’t dyno this one. The latest 409 made something like 265 or 270 but like most power runs it wasn’t set up like it would be on an airplane. 245-250 in airplane dress is more realistic.
 
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My apologies, I thought the torrent of memes would give it away. It was an in-jest way of highlighting the fact your question is rhetorical to many of us who have seen the sausage get suggested and rejected a time or two.

Basically the answer to your question is that the bigger asks in your wish list are straight up riddled with BS barriers an aviation neophyte or pedestrian would immediately consider obtuse. And they'd be right, but they'd also be tilting at the windmills by coming on here to describe the water. There'll be plenty of posts coming along to describe this sclerotic dynamic to you in more detail; I'm no longer interested in re-litigating that dead-end topic.

Wrt the smaller asks in your list, those are ultimately beholden to the unspoken inconsistency of a system that requires the seeking of an agreeable gatekeeper to lend his signature to ya, and all the machinations involved in placating and cultivating that unicorn once you find it.

So, do yourself a favor and just take the advice of post #6 from the get go. Good luck!
While a fun read, if I were the OP, I would be more confused after reading that than I was prior.
 
If some aircraft are able to have aftermarket turbo systems installed, then why not can something like above be installed
Two things. The cost of the paperwork and the cost of the testing to prove to the FAAs satisfaction that making the change has no adverse effect. Add on turbos have been around a long time and apparently the FAA bureaucracy has decided that they might be OK. Changes to internal engine parts - not so much.
The FAA cares about two things, paperwork and not making changes to anything.
 
Is there a reason something like this isn't available to certificated aircraft.
If some aircraft are able to have aftermarket turbo systems installed, then why not can something like above be installed.
In general, money and market are the main reasons. Every defined FAA type certificated product (aircraft, engine, propeller) starts with an approved type design. In order for that product’s TC designation to remain valid and airworthy, each product must conform to its type design at all times unless properly altered via one of several regulatory paths.

In the case of your stroker kit that would usually be one of the following: the TC holder/OEM can provide a stroker kit via a FAA approved revised type design; an OEM/Vendor can develop an approved Supplemental Type Certificate (STC) and produce stroker kits for sale to the public; or, an aircraft owner can initiate their own approved alteration via Part 43.

While the FAA approval costs are usually the 1st detractor, how the market/risk plays into the decision to provide stroker kits usually is the main reason OEMs/Vendors do not venture out on these types of upgrades.
If non-TSO avionics can be installed in certificated aircraft,
In general, installing non-TSO avionics is on opposite ends of the aircraft modification spectrum than adding a “stroker kit” so there is really no comparison per se. But for reference, an owner has basically 2 options if they want to change something on their TC’d aircraft: a part replacement or aircraft alteration.

For a part replacement (remove part A and install a new part A or part B) the replacement part must have an FAA approval (OEM part, PMA, TSO) in order for the aircraft to conform to its type design. There are exceptions for FAA defined Standard Parts, Commercial Parts, etc. but in general if that replacement part is not approved the aircraft does not conform to its type design.

But… in the case of non-TSO or other non-FAA approved parts it can still be installed on a TC’d aircraft under a Part 43 major or minor alteration (remove part A and install a part 34f2; or, add a part 34f2). By definition, this alteration modifies the aircraft type design to include the non-TSO avionics via the APIA signature in the aircraft record. Thus it is the “properly altered” side of the equation.
how the IA reads the 14 CFR 91
FYI: Part 91 will offer no guidance to the APIA involving aircraft maintenance. Part 43 is where all this guidance starts.
 
Lol, there are two approvals involved in this engine mod, the engine itself then whatever airplane it will be attached to.

simply put, ain’t worth the effort. The money needed you’re better off investing in a bigger airplane.
 
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I appreciate everyone's input on this. It is just odd that an engine like the io-390, which is only an io-360 with a bigger bore, can have a STC. While changing out the internals for a stroker kit does not.
 
If you’re referring to an o-340? There’s nothing new about it. Lycoming made the 0-340 in the early 50s and there are a couple of STC applications. The more recently popular 340 was developed for the experimental market.

The reason more engines aren’t developed and applied? Money. A manufacturer has to weigh cost of development and approval against potential for return on investment. In most cases it doesn’t pencil out.
 
I appreciate everyone's input on this. It is just odd that an engine like the io-390, which is only an io-360 with a bigger bore, can have a STC. While changing out the internals for a stroker kit does not.

It’s not “can have” vs. “can’t have”. It’s that Lycoming spent the time and money to type certify the 390, and some folks have pursued STCs to install them on a type certified airframe in place of other engines. At least one OEM is using the engine too, which likely helped push the engine toward getting type certified. The number of STCs for installing this engine on a TCd airplane is fairly small however, at least at this time.

The kits you’re interested in have no paperwork and to the best of my knowledge, nobody is trying to get them approved. It’s not that they can’t be approved.
 
It is just odd that an engine like the io-390, which is only an io-360 with a bigger bore, can have a STC.
Simple. There was a market for it. However, I believe in the case of the 390 there was previous history where a lot of the design was already worked out a number of years ago but mothballed. I think they may of even had a running prototype was the program ended.
 
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