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HP Increase on -E2D

avrojockey

Well Known Member
Patron
I have reached the limit of my regulation digging and knowledge and need some guidance from real mechanic types:

I have an RV-9A with an O-320-E2D with 160hp ECI Titan Cylinder Assembiles. There is no 337 or STC because it doesn't apply to airframe and the HP increase was not greater than 10%, but there is a logbook entry saying all worked performed IAW Lycoming service manual and AC43-13.

Special Airworthiness was issued with 25hr Phase 1 due to certified engine and prop combo. Is it correct one of the following 2 options must be done?

  1. Keep engine "certified" by complying with Lycoming Service instruction and ensuring a "C" is appended to the engine serial number
  2. Make engine experimental and remove the data plate

I would assume there's more aircraft value in option #1.

Also...does swapping the originally certified -E2D Slick Mag with an E-MAG make the engine experimental anyway requiring removal of the data plate or may this be covered by "C" stamp also?

Thanks...Tim
 
Perhaps I’m wrong, but I don’t think you have to remove the data tag to make the engine experimental. I thought that was an old wives tale. I look forward to hearing from the smarter ones out there on this...
 
Without the STC for the 160 hp upgrade your engine is technically experimental.

From what I understand STCs are airframe dependent and since there's no such thing as an STC for EAB, you can't have an STC for an engine on an RV. The only 160 STCs for -E2D are RAM and Ly-Con and they are for Cessna and Pipers. Plus you don't need and STC for just the engine because the because the TCDS E-274 covers almost all variants of the O-320...your not changing the TC by using -D2A cylinder assemblies on a -E2D.

There are examples for this in the certified world outside of already established STCs with simply a logbook entry (no 337) because it is considered a minor alteration. You're not changing the TCDS and your not increasing the HP over 10%. As long as you use serviceable Lycoming approved parts, follow Lycoming manuals, and do SI1304J (stamp "C" at end of serial number). In fact SI1304J is exactly for this purpose...you are changing the designation from a -E2D to a -D2A model by installing -D2A parts.

Check out this discussion...
https://www.supercub.org/forum/showthread.php?34406-!50-hp-to-160-hp-upgrade
 
Any engine conversion that increases the Horsepower of the engine is a major alteration and requires a 337 in the certified world. I held a FAA approved process spec, for the repair station, that allowed such conversions and was the approved data for the 337. I went back and forth with the FAA over this for years and finally got the approval. I was in the NY area and have been out of circulation for the past 8 years. Maybe something has changed but the FAA would not allow a conversion that involved a horsepower change without a337 for it. BTW an E2D has a different crankshaft and main bearing setup as compared to a D2A. So just replacing the cylinders with high compression ones is not converting it to a D2A.
Good Luck,
Mahlon
 
Any engine conversion that increases the Horsepower of the engine is a major alteration and requires a 337 in the certified world. I held a FAA approved process spec, for the repair station, that allowed such conversions and was the approved data for the 337. I went back and forth with the FAA over this for years and finally got the approval. I was in the NY area and have been out of circulation for the past 8 years. Maybe something has changed but the FAA would not allow a conversion that involved a horsepower change without a337 for it. BTW an E2D has a different crankshaft and main bearing setup as compared to a D2A. So just replacing the cylinders with high compression ones is not converting it to a D2A.
Good Luck,
Mahlon

Ok...I actually looked up 43 App A instead of relying on the internet. You're right!

So...how does one keep my engine "certified" in an RV with this HP increase? Can you even do a 337 for just an engine on an RV? Would the 337 application even be possible because the aircraft is not TC'ed in the Standard Category?

Thanks for the help!

What I'm trying to prevent is any perceived devaluation of the aircraft because it has an "experimental" engine instead of the certified engine/prop combo. I personally don't care what my engine label is...it's a great running engine. Maybe this is moot because it still a Lycoming and has 10 more HP.
 
Last edited:
Have read all the responses in this thread.

Looking up the tail number in your signature, I find that you are the aircraft owner and not the builder. Aircraft was manufactured in 2004. The FAA Registry lists the aircraft as EXPERIMENTAL with a Lycoming engine.

Most people believe that any engine in an EXPERIMENTAL aircraft is an experimental engine and will remain that way as long as it is in the airplane. The engine would need to be removed from the airplane and someone like an A&P would then need to inspect the engine and make some sort of log entry that the engine meets the original FAA Type Certificate so that it can be installed in a Type Certificated aircraft.

For use in your RV-9A, you do not need to do anything to the engine data plate and I do NOT recommend removing the data plate from the engine. Lycoming Engine data plates are suppose to be difficult to obtain but one can buy blank data plates on eBay at a reasonable price if you really need a different data plate.

The Operating Limitations (OpLims) are the document that must be followed for operation and or modification of YOUR aircraft. IF someone else modified the engine like you describe, then the OpLims should have been followed with required log entries and test flying. IF you are modifying the engine, then you must follow what the OpLims say about the change.

Mahlon knows more about engines that I do. I would trust his guidance on engines. I do know Lycoming made one 320 engine that had different front main bearings and that engine was not recommended going to higher compression over the 150 HP. I know most 320 series Lycoming engines have the same bore and stroke. MOST 320 going from 150 HP to 160 HP typically involve different higher compression piston and a thicker wall heavier piston pin that is used on the 160 HP engines.

Your original 1st question answer is: The engine is not "certificated" as long as it is installed in an Experimental airplane. Some may argue that as long as it is maintained by an A&P it will but that is subject to debate.

Question 2 answer: Do not remove the data plate. Somewhere I remember reading that one cannot remove the data plate but I am drawing a blank on the source. IIRC, only the manufacturer can remove or change the data plate.

IF there are some log entries by others for the work but the log is missing test flights, and you are attempting to correct inaccuracies in the logs, one needs to go back to the OpLims that are in the airplane now and also determine what OpLims were in the airplane when modifications were done. This will tell what needs to be accomplished to get the aircraft back into Phase II operations outside the test flight area.

Just my opinion and may not be worth any more than you paid for the info.
 
The Operating Limitations (OpLims) are the document that must be followed for operation and or modification of YOUR aircraft. IF someone else modified the engine like you describe, then the OpLims should have been followed with required log entries and test flying. IF you are modifying the engine, then you must follow what the OpLims say about the change.

IF there are some log entries by others for the work but the log is missing test flights, and you are attempting to correct inaccuracies in the logs, one needs to go back to the OpLims that are in the airplane now and also determine what OpLims were in the airplane when modifications were done. This will tell what needs to be accomplished to get the aircraft back into Phase II operations outside the test flight area.

Just my opinion and may not be worth any more than you paid for the info.

So here's an interesting wrinkle...DAR issued Airworthiness and OpLims with the engine already converted to 160HP. Before it was put in my ship it was overhauled and put in a Glasair, so I presume no record of flight test is required. Maybe this airworthiness issued in error as a certified engine/prop combo? (Not that it matters now because there's almost 700 hrs on the airplane.) The engine was topped 2 years after the airworthiness was issued and was done with new ECI Titan160HP cylinder assemblies (TIST04.1CA) to keep 160HP.
 
So here's an interesting wrinkle...DAR issued Airworthiness and OpLims with the engine already converted to 160HP. Before it was put in my ship it was overhauled and put in a Glasair, so I presume no record of flight test is required. Maybe this airworthiness issued in error as a certified engine/prop combo? (Not that it matters now because there's almost 700 hrs on the airplane.) The engine was topped 2 years after the airworthiness was issued and was done with new ECI Titan160HP cylinder assemblies (TIST04.1CA) to keep 160HP.

Sometimes a DAR can make a mistake. People are human and can make mistakes. The mistake is not an issue if no one gets hurt.

My RV-6 had a 25-hour phase I test period because I had a certificated engine and prop combination. The only thing about the engine is that it had a data plate that was for a B2B engine and that is Fixed Pitch prop. I used the Lycoming instructions to convert the engine to constant speed operation.
 
My take is this. Your engine could not be installed in a certified aircraft as a certified engine. It is modified from its original state and those modifications are not supported by FAA approved data or by FAA approve Maintenance record entries. Even, if all the work was done according to Lycoming maintenance data the certification was lost when you did two major alterations without approved data. The high compression cylinder installation and the electronic ignition installation. The rest of the engine beyond those modifications is certified assuming no other alterations took place. If the engine was taken off the experimental aircraft and low compression cylinders and mags were reinstalled it would then be able to be used on a certified aircraft with a sign off for an annual inspection for that aircraft. So your engine is a certified engine that has been modified from its' approved data. It's not an experimental automotive engine. Its not a experimental lawn mower engine. it's not a experimental snow mobile engine. It's a certified but modified Lycoming engine and can easily become a certified unmodified Lycoming engine. The rest is semantics. Some would call your engine experimental because of the mods and others wouldn't. It's kind of in the eye of the beholder. In my mind it's a certified engine that needs some work to be installed in a certified aircraft. My logic is this; if a certified engine had let's say 4 bad cylinders that wouldn't pass annual inspection. The aircraft would be grounded until the engine was repaired properly. The engine didn't loose the fact that it was a certified engine because it failed the inspection due to bad cylinders. It's still certified but unairworthy and it just needs to be brought back to spec. Same goes for your engine. It wouldn't pass an inspection in its current state and would be certified but unairworthy because of the mods. But it could be made airworthy if repairs were made to bring it back to spec.
Leaving the data plate on or off has no bearing on the engine's real state. As long as you keep the data plate and can reinstall it, the engine will be whole again. It's just a part that should be on the engine and is required by the FAR's to be certified. So to me you should leave it on.
If you remove the data plate and loose it then you will need to get a replacement from Lycoming, if the engine were ever to be considered certified, and that may be difficult because the FAA has to issue a letter to Lycoming saying it's OK to issue a new one. They might not do that until you unmodify the engine and prove it is unmodified. Bad can of worms to get into....
That's the way I look at it and am pretty sure the FAA would to. This all applies to the engine in the certified world and it's use in a certified aircraft. Use in it's current state on an experimental aircraft may be up to the DAR or FAA person certifying that experimental aircraft, I don't know the regs or stipulations for a modified certified engine as used in a non type certificated experimental aircraft but would assume again that that it's designation certified or non certified would be in the eye of the FAA doing the inspection..
Just my opinions but I hope it helps with your quest.
Good Luck,
Mahlon
 
What I'm trying to prevent is any perceived devaluation of the aircraft because it has an "experimental" engine instead of the certified engine/prop combo.

I doubt any buyer will care much if your engine was kept "certified". True, if it was maintained and signed off by an IA for every maintenance inspection and procedure (other than ones permitted for owners), a buyer might consider the engine to be well-maintained and pay a bit more. But the premium will be offset by the cost of professional maintenance under IA supervision and your inability to do anything much more complex than an oil or plug change.

Fly often, change your oil regularly, cut open the oil filter, borescope the valves and document it in your logbook. This will mean more to a buyer than a "certified" stamp. At least, it would to me.
 
it comes down to this: the FAA does not care what you call an engine on an EAB. the rules allow you to put anything on the airframe. the FAA only cares that an engine conforms to the TCDS of the engine and the airframe that it is on when dealing with a type certificated aircraft. so, when you put an engine that was on a EAB on a type certificated engine, there had better be a statement in the logs that the engine meets the TCDS. I would argue that the statement must be by someone holding a IA unless it is done during the sign off for a overhaul and then it is covered by the statement that it was overhauled IAW with the lycoming overhaul manual and the parts list contains the proper part numbers and certifications. personally I would not do it without a teardown to confirm parts anyway, so might as well overhaul it then.

the problem with saying that if you maintain the engine as a certified engine with it on a EAB, it is still certified, is that there is no requirement to have a A&P maintain the engine on a EAB. so there is no way to prove that it has been maintained IAW the TCDS and applicable part 43 FARS. No A&P would hang an engine on a type certificated aircraft that came off an EAB without a conformity inspection. Its a good way to get your ticket pulled.

as to the STC to make a 150 into a 160, with the RAM stc there are actually two stc's you have to buy. one is for the engine conversion and is does not relate to the airframe at all. the second one you need to buy is to put the engine on the airframe. You could buy the STC from ram and do the conversion on an EAB. the only reason to do that is then there is the stc paperwork there if you wanted to put that engine on a type certificated aircraft. however, you would still need to get the second STC do do that install and do a conformity inspection of the engine. there is no way to change the HP on a type certificated engine without the STC. years ago you could do it on a field approval on a 337 but the FAA wil not do that anymore.

bob burns
RV-4 N82RB
 
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