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180hp IO-360 variants

N804RV

Well Known Member
Has anyone ever compiled a list of IO-360 variants that are compatible with RV-6/7/8?

Specifically: 1. No rear induction 2. No "lightened" prop-flange

Going through Lycoming's SSP110-2 seems like a daunting task. I'm hoping someone's already come up with a cheat sheet.
 
My list of engines that work well on an RV7A without major integration trouble is...

O-360 A1F6 modified for precision fuel injection (incl purge valve) dual P-mags and an auxiliary alternator on the vacuum pad instead of a vacuum pump.

PS, there’s a rumour circulating that Lycoming built the exact same engine configuration more than once but it’s never been proven. :)

Bevan
 
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Has anyone ever compiled a list of IO-360 variants that are compatible with RV-6/7/8?

Specifically: 1. No rear induction 2. No "lightened" prop-flange

Going through Lycoming's SSP110-2 seems like a daunting task. I'm hoping someone's already come up with a cheat sheet.

I was trying to find the same info a few weeks ago for 0-320 and IO-320 compatible variants for the RV-9 (RV-6/7/8 would be a bonus).
 
The thing is, if you find a good engine that isn't quite right, you can change parts and reconfigure it to be what you want.
 
The thing is, if you find a good engine that isn't quite right, you can change parts and reconfigure it to be what you want.


Hoping not to spend another 2 grand on an engine just cause I got one with rear induction.

And, after going to Lycoming's factory school last year, and learning about "lightened" prop flanges, I definitely don't want one of those.
 
Hoping not to spend another 2 grand on an engine just cause I got one with rear induction.

And, after going to Lycoming's factory school last year, and learning about "lightened" prop flanges, I definitely don't want one of those.


What's the deal with "lightened" prop flanges ?
 
What's the deal with "lightened" prop flanges ?


The instructor at the Lycoming service school was pretty adamant about the lightened prop flange not being suitable for aircraft approved for aerobatics. After reading up on this, I think this is geared more toward light-weight competitive aircraft, like the Pitts S-1 and Laser 200, with the AEIO-360 200hp engines.

There have been a couple of spectacular failures, mostly on competitive aerobatic aircraft. But, there was also a pretty scary accident on a Britten Norman Trislander in 2009, that resulted in the Australian CAA issuing an AD for a 25 hour inspection on these prop flanges.

I'm not an expert on this topic. So, if anyone has any more knowledge, please feel free to share.
 
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What's the deal with "lightened" prop flanges ?

The original horizontally opposed engines all had crankshafts with lightening holes. Not sure what year but Lycoming changed the crankshaft prop flange from one with lightening holes to one that used a solid flange.

I have seen more Lycoming engines that have lightening holes in the crankshaft prop flange than ones without. It is just the last 20 or 30 years that the sold crankshaft prop flange has been available on all new engines coming from Lycoming. I have been flying my RV-6 with a crankshaft that has lightening holes in the prop flange for more than 20-years.

I also have been to the Lycoming Engine School before the school changed instructors.

Would love to see the data where this old wives tale of Lycoming crankshafts with lightening holes in the prop flange being no good got started.

Yes the solid prop flange crankshaft is stronger but with thousands of RV flying with crankshafts that have lightening holes in the prop flange it is not necessary a requirement for a safe RV aircraft.

Show me the data where the new design Lycoming Crankshaft flange is required for what we do in our RV aircraft. Anyone can say anything on the internet and I tend to NOT believe everything I read without reference data.
 
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Parallel Valve Titan engines link

Continental builds both standard ( i.e. with configurations like those offered by VANS ) and more customized engines. Here is the address for the standard options;

http://www.continental.aero/titan/vans.aspx

These have parallel valve cylinders with steel barrels and the crankshafts have the solid .44" thick flange. A roller lifter valve train and other modern characteristics are included. Continental created these engines to be drop in configurations so that no modifications are necessary to the firewall forward kit.

Continental does not build an angle valve (200HP) engine. To get close, the Titan 370 high compression engine is rated at 195 HP. It is not one of the standards found on the link above.
 
I finally found a copy of the pertinent service bulletin. Although, it is listed by Lycoming as a current SB, I couldn't find it on their website. But, I found an old copy of it on Aviat's web site.

It only applies to AIO and AEIO-360 engines. I guess we don't have to worry about "lightened" prop flanges on our RVs, because our "less maneuverable" aircraft don't impose the high loads on the prop, like the unlimited class aerobatic planes do.

https://aviataircraft.com/wp-content/uploads/2016/01/e331.pdf
 
Aerobatics

The Lycoming problems with aerobatic crank failures goes back at least to the late 70's. The general belief is that it is related to gyroscopic maneuvers. The light weight props including MT and Hoffman and more recently Hartzell and Whilwind composite appear to have greatly reduced this issue. Personally I would not hesitate to use a lightening hole crank with a wood or wood/composite prop on an aerobatic airplane that was not used for gyroscopic maneuvers. I put 1k hours on a Pitts 0 360 parallel valve with Sensenich fixed pitch metal. Standard flange, no lightening hole crank. Lots of flat spins an multiple snaps, etc. As far as I know the Pitts S2B still requires a 100 hour inspection on the flange with Hartzell metal prop even with the heavy flange.
 
Crank

I flew a S2B that previously had the prop depart at just over 100 hours from new. New engine flange cracked after a few hundred hours.
 
It is in Van's Manual

Has anyone ever compiled a list of IO-360 variants that are compatible with RV-6/7/8?


Yes.

Van's aircraft includes info on engines in Section 11 of the construction manual.

It is in the paper copy of my RV-6 and also in the PDF Preview version.

The DASH number following the 360 will describe how Lycoming configured the engine. Many of the versions can be converted to another DASH number version by changing parts.

I tend to stay away from all the 76 Series engines and ones that have the dual mag with single drive. I also prefer to stay away from the engines that have harmonic dampeners on the crankshaft. (more weight and extra parts requiring more work and money at overhaul time)

Wikipedia starts listing some of the versions of the Lycoming 360 but does not give the breakdown that Van's does in the manual.

Just picked up my paper copy of the RV-8 preview plans. It appears to have the same engine info that my RV-6 manual has.
 
Yes.

Van's aircraft includes info on engines in Section 11 of the construction manual.

It is in the paper copy of my RV-6 and also in the PDF Preview version.

The DASH number following the 360 will describe how Lycoming configured the engine. Many of the versions can be converted to another DASH number version by changing parts.

I tend to stay away from all the 76 Series engines and ones that have the dual mag with single drive. I also prefer to stay away from the engines that have harmonic dampeners on the crankshaft. (more weight and extra parts requiring more work and money at overhaul time)

Wikipedia starts listing some of the versions of the Lycoming 360 but does not give the breakdown that Van's does in the manual.

Just picked up my paper copy of the RV-8 preview plans. It appears to have the same engine info that my RV-6 manual has.

Thanks for the reply!

But, that's just a regurgitation of https://www.lycoming.com/sites/default/files/SSP-110-2 Certified Engines.pdf. You can get that info in various locations. But, trying to figure out which ones are vertical, forward, or rear induction is still that 'daunting' task I referred to in my original post.
 
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