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which IO-360? My head hurts!

kevinsky18

kevinsky18

Well Known Member
My head is spinning. I'm sure many of you have expereinced the same thing when trying to decide on your power plant.

This is for an RV-8

A few descions have been made. First it will be an IO-360 with electronic ignition and high compression pistons without the counter blanced crank and I'll be getting the constant speed crank though I'm not certain I'll be putting on a constant speed prop.

Also I will be buying from Aero Sport because of their excellent rep and I live in their home town.

But despite all this I'm looking at their web page and I still see a number of options. What are the key differences between the A, B, M and M1B Engines? Except the obvious price difference.

here's a link to there options and prices. I'd be interested in what others would go with and why.

http://www.aerosportpower.com/Prices.htm
 
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Good timing for me as I'm trying to decide on an engine too. I want the exact same engine, but have yet to pick a builder.
 
kevinsky18 said:
My head is spinning. I'm sure many of you have expereinced the same thing when trying to decide on your power plant.

This is for an RV-8

A few descions have been made. First it will be an IO-360 with electronic ignition and high compression pistons without the counter blanced crank and I'll be getting the constant speed crank though I'm not certain I'll be putting on a constant speed prop.

Also I will be buying from Aero Sport because of their excellent rep and I live in their home town.

But despite all this I'm looking at their web page and I still see a number of options. What are the key differences between the A, B, M and M1B Engines? Except the obvious price difference.

here's a link to there options and prices. I'd be interested in what others would go with and why.

http://www.aerosportpower.com/Prices.htm
Click to expand...
Here is what Lycoming has to say:
http://www.lycoming.com/support/troubleshooting/resources/SSP204.pdf

Best bet for you buying an Aero Sport Power engine would be to call Bart or Sue and ask more questions.

Sounds like you want a PARALLEL valve 180 HP engine. My best guess is that the A and B are both updraft intake and the M is horizontal intake.

From the above Lycoming link:
IO-360-M1A 180/ 2700/ 100/100LL 8.50:1 Same as ?B1E except has a front mounted propeller governor pad and a front mounted fuel injector
(my note: Bart may not be using the front mounted governor so you will need to check on this.)

It once was said that Lycoming never built any two engines alike.

If you are talking about an IO-360 angle valve 200 HP engine, then it has a counterweighted crank. You may be wise to look at the IO-390-X. It is the same weight as the 360 but 10 HP more. I also understand that it costs less than the 200 HP 360. http://www.lycoming.com/engines/series/390-series-engines.jsp

I hope I did not confuse you more. Read a little bit in the Lycoming link and it will not make 100% sense but it will give you a little idea on what the letters and numbers stand for.
 
Start with the big picture, and ask yourself a few basic questions:

1. Do you want a heavy, 200 hp, angle-valve engine, or a lighter, 180 hp, parallel-valve engine? The IO-360-A series engines are the heavy, 200 hp, angle-valve ones. The IO-360-B and -M series engines are the lighter, 180 hp, parallel-valve ones.

The IO-360-A series engines have the fuel injection servo on the front of the oil sump, and they get the smooth front lower cowling.

2. If you want the 180 hp engine, where do you want the fuel injection servo? If you want it on the bottom, with the induction air inlet in a scoop on the lower cowl, then you want an IO-360-B series engine. If you want the smooth front lower cowling, then you want one of the IO-360-M series engines.

As to the difference between an IO-360-M1A (no such thing as an IO-360-M) and an -M1B, you should be able to find that on the FAA Type Certificate Data Sheet. Go to the FAA Web site, click on Licenses & Certificates, then click on Type Certificate Data Sheets (TCDS). Type "IO-360" in the Search box, click Go, and look for a result from Lycoming. The crazy FAA web site will then give you a quick web IQ test, as it presents you with a useless series of pages, each with a magic link that you must find to get to the next page in the series. The FAA will eventually tire of this game, and one of the links will actually give you the TCDS. I won't put the URL here, as they seem to change them every few days, just to drive us normal folks nuts.

Once you are in the TCDS, look for a section near the end that lists the differences between engine models.
 
IO-XXX-XXX

As the old Drag Racers used to say, "there ain't no substitute for cubic inches and horsepower"!!!!!

I originally wanted the 180 hp fixed pitch combo on my RV-8. I ended up with an angle valve 200hp IO-360-A3B6D from a Mooney 201. It was such a good deal, I had to take it. I ended up with a yellow tagged constant speed prop for $3500. I sent all the engine parts out to be certified, rebuilt it myself and ended up with a certified engine-prop combo. Yes, It's at least 40lbs heavier than the parallel valve engines, but it's stressed for 200hp, the others?

After 72 hrs flying, I am soooo glad it ended up this way. I can cruise at 65% power at 7500ft and see 177-181 KNOTS TAS depending on OAT.

I say all this to say that if I had sufficient funds, I would get the IO-390-X with a constant speed prop. with this combo, you can slow down to cruise with your 150-160hp buds and burn the same or less gas in GPH. As an example, the other day I did the above mentioned cruise for about 45 min. landed, then the next day I flew over an hour at 15-17in manifold pressure and 2300rpm. TAS at 4000 and below was 130 Knots. That's about 150mph. When I refueled, my fuel burn was 7.03 gph!
 
Angle Valve an Horsepower my Vote if you have $$$$$

My choice is Horsepower!!!! Go with the angle valve IO-360A1B6 if you want to use High compression pistons over 10:1 at 200HP +engine or the IO-360A1A which is a lighter non counterweighted crank and keep the compression at around 8:75:1 or under and don't forget to add a C/S prop and you will be amazed at the takeoff and climbout!!!!!! The added horsepower and C/S prop will take you in and out of places that you could not imagine,,,,, Have you ever been too Leadville, CO or Telleride, CO in the summer????? Don't worry about the added weight. It has never bothered me what so ever. If you have the money go with the 390.
 
The IO-360-A is a 200hp angle valve, horizontal, forward facing air inlet engine.
The IO-390 is basically the same as the IO-360-A except is has slightly larger displacement rating it at 210 HP and has the prop gov is located on the front left area of the crankcase instead of the rear accessory case.
The IO-360-B is a 180HP parallel valve vertical induction engine.
The IO-360-M is a 180 HP horizontal , forward facing, induction engine.
The IO-360-B is the fuel injected version of the O-360-A1A.
The IO-360-M is the same engine as the IO-360-B but has the induction system that the IO-360-A uses installed.
Hope this helps.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."
 
Head still spinning. I guess the question needs to be asked. What are the pros and cons of the smooth cowl verses the one with the air intake on the bottom?

Are there performance gains either way? Building issues?

I am trying to stay light, cheap and simple so I've decided on a FP prop. I was thinking of a 180 version with higher compression pistons to get the best weight to power ratio out of the plane.

What's the highest compression one can go to on an IO-360 without a counter weighted crank and what HP would that generate?
 
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kevinsky18 said:
What's the highest compression one can go to on an IO-360 without a counter weighted prop and what HP would that generate?
Click to expand...
Kevin,

Ask the builder about minimum octane rating. Eventually they are going to ban 100LL and when they do, all these "high" compression engines may have to lower their compression to run less than 100 octane unleaded fuel.

Just something to think about as you make your engine selection.
 
Rather than looking at it from the angle of smooth vs. snout cowl, look at it in terms of horizontal vs. vertical induction. Horizontal implies cold air induction, and yes, you will get more horsepower with that configuration (all else equal).

Building issues...Van's sells a FWF kit for horiz induction with Bendix/Precision injection. If you go with Airflow Performance injection & horiz induction (which of course I would encourage you to do, it kicks butt), then you might have to get inventive with control cable routing and hardware. Don't let me overstate the complexity...it's not a huge deal and the solutions are straightforward. There are many flying examples of this setup with web sites out there... :rolleyes:
 
Which engine and how much compression

[/QUOTE]
I am trying to stay light, cheap and simple so I've decided on a FP prop. I was thinking of a 180 version with higher compression pistons to get the best weight to power ratio out of the plane.

What's the highest compression one can go to on an IO-360 without a counter weighted prop and what HP would that generate?[/QUOTE]

Kevin:

Definitely go with 180 hp if you want less expensive (nothing related to aircraft engines is cheap.) If you go 9:1 compression on the 180 hp, you will have an engine that, all other things being equal, should make TBO.

9.5:1 will yield a 25% loss in TBO, and we wouldn't recommend 10:1 or higher in the p/h 360. You'll have an engine that will last around 1000 hours. We generally only use 10:1 compression or more with aerobatic and race pilots.

But, if you want most bang for the buck and can stand a few thousand more, my bet would always be on the IO-390 for the RV-8. Only 9 lbs heavier than the a/h 360 and an easier 15 hp gain with stock compression and a 2000 hour TBO.

Good luck!
 
Ok things are starting to come together.

I?m thinking the IO-360-M1 Constant Speed Engine (coupled to a FP prop) with Superior Roller Lifter Components. $24,900.00 Plus 9.2:1 pistons add $300.

I know I want electronic ignition so now I need to decide on that. Which type and single or dual?

Getting closer.

Now next dumb question. Is the smooth cowl vs snout debate finished now that I have decided to go with the horizontal model? I mean is there only one cowl choice for this engine configuration?
 
Governor position

I believe that a front or rear mounted governor is available for the IO-360-M series engines, does anyone know if a front mounted governor fits inside a Van's cowling?

Pete
 
kevinsky18 said:
I?m thinking the IO-360-M1 Constant Speed Engine (coupled to a FP prop) with Superior Roller Lifter Components. $24,900.00 Plus 9.2:1 pistons add $300.

I know I want electronic ignition so now I need to decide on that. Which type and single or dual?
Click to expand...
For what it's worth, I have basically the same engine and options. I went with one Lightspeed ignition and one mag, to hopefully straddle the line between the performance/economy benefits of EI and the known-quantity factor of traditional mags. I think Dan C has the same ignition setup.

Is the smooth cowl vs snout debate finished now that I have decided to go with the horizontal model? I mean is there only one cowl choice for this engine configuration?
Click to expand...
Yep, if you go with horizontal induction there is only one cowl option. If you tell Van's on the finish kit order form that you have an IO-360-M1B you'll get the right cowl.

mcb
 
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kevinsky18 said:
Now next dumb question. Is the smooth cowl vs snout debate finished now that I have decided to go with the horizontal model? I mean is there only one cowl choice for this engine configuration?
Click to expand...
Basically, yeah. When you order your finish kit and FWF kit in particular, make sure you tell Van's exactly what configuration you'll be using...specifically for the IO-360-M1*:

- horizontal intake
- parallel valve
- fuel injected (tell them what mfr FI system)

i.e., go here: http://www.vansaircraft.com/pdf/engine_id_form.pdf
 
Sorry maybe I got confused reading Aero Sports page. I'm not after the M1B I'm after the regular M engine.

In their description they say (m2) for fixed pitch and (m1) for constant speed. That's why I said IO-360-M1 I guess I should have just said IO-360-M.

That said I'm not 100% certain in the difference between the regular M constant speed and the M1B. . .

Arrrg head spinning again
:D
 
kevinsky18 said:
What are the pros and cons of the smooth cowl verses the one with the air intake on the bottom?

Are there performance gains either way?
Click to expand...
As far as performance, Van found no difference. There is a tiny bit less MP with the smooth front cowling, but that seems to be balanced out by a bit less drag. Van figures the speed is the same, within his ability to measure it. At least this is the way I recall the description in the RVator when Van reported the results of his testing on the RV-8 proof of concept aircraft.
 
Kevin Horton said:
There is a tiny bit less MP with the smooth front cowling, ...
Click to expand...
Do you have data to support that? Every bit of data I have says it's the other way around. With my horizontal induction setup I get higher MP than every other RV (and Glasair and Lancair) I've ever flown against...and that's BEFORE I open ram air. Cross checked readings with engines stopped. Not trying to be competitive here, just stating fact as I see it.
 
dan said:
Do you have data to support that? Every bit of data I have says it's the other way around. With my horizontal induction setup I get higher MP than every other RV (and Glasair and Lancair) I've ever flown against...and that's BEFORE I open ram air. Cross checked readings with engines stopped. Not trying to be competitive here, just stating fact as I see it.
Click to expand...
Dan - you have some good test results for your modified version of Van's snorkel induction system. Your ram air mod looks to be worthwhile. But as far as I can tell you have never tested your aircraft and engine with an induction air scoop on the lower cowl. So I am not sure which test data you have that shows you have more MP than you would have with a scoop on the lower cowl that went directly to the air box. Have I missed something? Show me the data. :)

Van's original RV-8 proof of concept aircraft had a scoop on the lower cowl, going to an air box. He later modified it to have the prototype snorkel induction system, with a smooth front cowl, and reported the results in the RVator, first issue of 1998. He reported a loss of 0.1" MP when switching to the smooth front cowl, but saw a speed gain of 2-3 mph. He said that the testing with the smooth front cowl was in winter, so the density altitudes were different. He considered that the performance was essentially equivalent between the two cowl types.

Van's testing was with the two cowl types on the same aircraft, same engine, and I assume the the same MP guage and ASI, etc. However, it wasn't quite the same thing as having a 180 hp IO-360-B with bottom-mounted injection servo vs IO-360-M1B with front-mounted fuel injection servo. It is possible that there may be some additional difference due to the different injection servo to engine air routing.
 
Ah...I see what you're saying, Kevin. I just wouldn't want anybody to feel like they're going to sacrifice any performance going with a horizontal induction setup. I know & fly with at least two guys with vertical who wish they had horizontal in a quest for more HP.
 
This thread comes at a good time for me. My head also hurts. Is vertical or horizontal induction easier to build? Or is the build complexity pretty much equal between the two?
 
200 hp comes only in counter weight

kevinsky18 said:
A few decisions have been made. First it will be an IO-360 with electronic ignition and high compression pistons without the counterbalanced crank and I'll be getting the constant speed crank though I'm not certain I'll be putting on a constant speed prop.
Click to expand...
All the angle valve 360's or 390 200/210HP are counter weight cranks. So if you want non-counter weight than you will be looking at a parrellel valve 180Hp engine. Non-counter weight is a good choice if you want to save weight and are going to do formation flying (rapid throttle movements which can de-tune counter weights).

Since you want "high compression" pistons you are not going to buy a crate Lycoming, so your into the experimental land. Give Mattituck a call. Why high compression. Do you want to make sure you can't get gas for it when 100LL goes away? It is a real possibility we will go to UL (unleaded) gas in the near future, something like 93UL or may be 95UL. High compression, say over 8.5:1 or 8.7:1 will not be happy. Suggest stock compression, but pick your posion. If you want power, I would go with the angle valve 360/390 and take the weight. You relize 20 extra HP is only an extra 7 mph.

All the other things, ignition, induction can be decided later and probably assembled at any shop. Consider the ROLLER CAM. That is one nice option. It saves HP and just about eliminates any cam / tappet issues.

Horz verses Vert Induction = very little difference if any in performance. However with the scoop less cowl (horz induction) you may save a little drag, 1 mph? 2 mph? With Horz you can get into some exotic aftermarket sumps, like cold induction or composites, the latter not recommended due to issues IMHO. Are you building an unlimited acro plane or sport plane? Suggest keep it simple and less expensive. You can spend a fortune on special parts. The biggest advantage with the horz sump in my opinion, besides the style points (no scoop) mentioned above, is 4-into-1 exhaust fit a little better.
 
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gmcjetpilot said:
Well you want a 180 hp because all the angle valve 360's or 390 200/210HP are counter weight cranks.
Click to expand...
Not true. IO-360-A1A is a 200hp angle valve without the same counterweights that the -A1B6 (for example) has. Let the TCDS be the authority. There's gonna be some conflicting info posted here! :rolleyes:
 
Dang you are good

dan said:
Not true. IO-360-A1A is a 200hp angle valve without the same counterweights that the -A1B6 (for example) has. Let the TCDS be the authority. There's gonna be some conflicting info posted here! :rolleyes:
Click to expand...
DANG! YOU GOT ME. :D You are right, thought no one would notice, but I think most of the ECI, Superior, Aerosport, Mattituck IO360 angle valves are based on counterweight crank model. That non-CW crank angle valve was a special engine for a Cessna 172 XP or something.

I guess you get the IO360 angle valve built up with the non-counterweight crank for the same money?
 
gmcjetpilot said:
DANG! YOU GOT ME. :D You are right, thought no one would notice, but I think most of the ECI, Superior, Aerosport, Mattituck IO360 angle valves are based on counterweight crank model. That non-CW crank angle valve was a special engine for a Cessna 172 XP or something.

I guess you get the IO360 angle valve built up with the non-counterweight crank for the same money?
Click to expand...
For fun... I had an IO-360-A1A in a Mooney M20F (the M20E used the same one) and an IO-360-A1B6D in a Mooney 201. There was a noticeable difference in vibration and noise level from the -A1A to the -A1B6D, which is one reason I rationalized going with the -A1B6 in my RV-7.
 
Something else to think about, rods and prop

Quote:
Originally Posted by gmcjetpilot
Well you want a 180 hp because all the angle valve 360's or 390 200/210HP are counter weight cranks.


Not true. IO-360-A1A is a 200hp angle valve without the same counterweights that the -A1B6 (for example) has. Let the TCDS be the authority. There's gonna be some conflicting info posted here!
__________________
)_( Dan
RV-7 N714D (1200+ hours)
EAA Technical Counselor & Flight Advisor
www.rvproject.com / www.weathermeister.com / www.weighmyplane.com
Click to expand...

FYI

IO-360A1A / 200HP is an angle valve engine with a non counterweighted 180HP crank and connecting rods to match this crank which are much lighter and have different connecting rods and bolts than the Lycoming counterweighted IO-360A1B6. The counterweighted IO-360A1B6 crank is heavy as are the connecting rods. the A1B6 rods are tanks and the rods bolts are not cheap BTW.
The non counterweighted Lyco crank with High comp and C/S prop is the problem if running a Hartzell C/S Metal prop.... Hartzell will not stand behind there product with the prop I'm running if the crank is not the Lycoming counterweighted crank. It has to do with harmonics and a host of other problems.. Compression and the wrong parts can kill the prop / crank if not matched.

Just something to think about.... Do you want Horsepower, speed, 2,000 hour TBO, Weight issues, Go Fast, Or on a budget, or prop selection????

I wanted horsepower and didn't worry about the weight as I'm a slender 145lbs. So the added weight of my Lyco A1B6 crank and heavy connecting rods in my -6 did not bother me that bad and I love the Horsepower on takeoff and climbout.

One thing to thing about. The faster you can get to cruise alltitude, the sooner your going to be in cooler thinner air and the sooner your going to get from point A to B.

One more note: I build my own engines and I pay much attention to detail and my present engine in my-6 is VERY SMOOTH. It is a true 10:45-10:5:1 compression with 20degrees of ignition timing and a well balanced fuel system. CHT's are in the 325F range with 80F days. I'm not afraid of the high compression as the engine is more efficient and yes it makes more Horsepower, but one must respect and not run it at 100% 24/7 . Fuel burn on takeoff is High, but at cruise it is less than most lower compression engines because it is more efficient.

High alltitude your not making much power and the higher compression is a BIG plus!!!! But you must respect it and do not lean the dang thing out to the max or your going to burn a piston.

Taking care of a HOTROD engine is all in the hands of the owner / pilot and if one is not up and up with everything, go low compression 180HP and run the sh$%^ttt out of it and don't worry about it.
Cheers.....
 
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What everyone kind of forgot to mention here is weight! There is no substitute in the RV's for making them light. The "heavier" RV's (sorry if I'm accidentally insulting anyone - it's not intended) that are 1200-1300lbs empty are nowhere NEAR as fun to fly as the ones that weigh 1050-1150 lbs empty. Don't think it makes a difference....go fly both and you'll see that when you're yanking & banking really tight/hard/&sharp that extra weight on the nose makes a huge difference. Take an RV4 with a 320 vs. a counterweighted 360 and they feel like completely different airplanes. Same with the other series.

I know several people are fan's of the cw'd cranked 360's, but personally I think the sweet spot in these planes is a plain old parallel valved injected 360 with a c/s prop. I know there is "no substitute for raw hp", but come on, it's not like any RV's suffer from performance problems anyway :) The 390 is a neat engine and lots of people are using it, I'd rather save the weight and have a nicer flying plane - but that's just me.

It's interesting to see this thread, because I agree with things that George, Dan & Alan have all posted - which is a rarity for me!

Opinions are like you know what.....

Just my 2 cents as usual!

Cheers,
Stein.

P.S....if we really want to get going on crazy Lyco's - we should mention the 180hp counterweighted parallel valved engines too (the old "F" series)!
 
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I agree

SteinAir said:
What everyone kind of forgot to mention here is weight! There is no substitute in the RV's for making them light. The "heavier" RV's (sorry if I'm accidentally insulting anyone - it's not intended) that are 1200-1300lbs empty are nowhere NEAR as fun to fly as the ones that weigh 1050-1150 lbs empty. Don't think it makes a difference....go fly both and you'll see that when you're yanking & banking really tight/hard/&sharp that extra weight on the nose makes a huge difference. Take an RV4 with a 320 vs. a counterweighted 360 and they feel like completely different airplanes. Same with the other series.
Click to expand...
I know several people are fan's of the cw'd cranked 360's, but personally I think the sweet spot in these planes is a plain old parallel valved injected 360 with a c/s prop. I know there is "no substitute for raw hp", but come on, it's not like any RV's suffer from performance problems anyway :) The 390 is a neat engine and lots of people are using it, I'd rather save the weight and have a nicer flying plane - but that's just me.

It's interesting to see this thread, because I agree with things that George, Dan & Alan have all posted - which is a rarity for me!

Opinions are like you know what.....

Just my 2 cents as usual!

Cheers,
Stein.

P.S....if we really want to get going on crazy Lyco's - we should mention the 180hp counterweighted parallel valved engines too (the old "F" series)!
Click to expand...

I agree with everyones thoughts. I've flown light RV's and heavy RV's and there is a trade off! It's all about what a person wants, aerobatics, light controls, cruise, climbout, getting out of a 9,000ft density airport, etc. etc. Light nibble controls or the other, a heavy RV is not as much as fun to fly as a light one..........!!!!!

If one weighs 200lbs. go light ...... If one is 145lbs like me go with the other and juggle the HP versus weight. Weight is an issue with any airplane....... Less weight creates a bundle of fun in many areas.

I think everyone has there limits and yes Light is the best way to go. I took the middle of the spectrum and I'm happy, but if two big bubbas got in my-6 would not be much fun to fly loops and such with even with the added HP....
 
rv969wf said:
High alltitude your not making much power and the higher compression is a BIG plus!!!! But you must respect it and do not lean the dang thing out to the max or your going to burn a piston.
Click to expand...
Or just keep on leaning further... :D

Dag bernit Dan...you just couldn't let a thread go without the letters "L", "O", and "P" coming into play?!
 
HP

dan said:
Or just keep on leaning further... :D

Dag bernit Dan...you just couldn't let a thread go without the letters "L", "O", and "P" coming into play?!
Click to expand...
Click to expand...

OK, I've done the lean of peak at high alltitude,,,,,,, but I don't like flying slow..... Lean of Peak takes away Horsepower and my engine runs very cold moving air and not enough fuel through my engine.... If I run LOP I'm seeing CHT's around 275F and I can't do this,, so I keep it fat or should I say at 75-100F rich of peak and make power and speed.

I understand the LOP..... at High manifold Pressure....I've seen 30.5" at 800 MSL and OMG, please keep it 125-150F rich with what I'm running. At alltitude.... say 8,000 ft YES I bring it back but with in reason.
 
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If you want a light plane, it doesn't mean you have to forgo the angle valve. There are lots of ways to save weight other than putting in a lighter engine. My IO-390 and Hartzell powered RV-7A weighed in at 1078lbs.

Scott
N653S RV-7A
91 hours
 
Just to tip this thread back on track.

I have one outstanding question and that's the difference between the different IO-360-M engines.

I'm looking at Aerosports pricing page. http://www.aerosportpower.com/Prices.htm
and there is a $2000 price difference between a IO-360-M (M1) Constant Speed with Lycoming roller tappets and an IO-360-M1B with same roller tapets.

I looked at the Lycoming link for the differences in engines and I can't seem to see any except I think the M1B has a prop govenor in a different spot. . .
 
Engine Weights

I copied this off the Yahoo Lycoming Group:

Re: Engine weights

--- In [email protected], "Carsten <cschanche@w...>"
<cschanche@w...> wrote:
> Hello group,
>
> Does anyone have the weight comparisons between the O-320 and O-360,
> or IO-320 and IO-360?
>
> Carsten
> RV-7A wings

My Lycomming "DATA PAK" from 2002 Airventure in Oshkosh lists the
following dry weights:

Model Comp Ratio HP RPM Dry Wt

O-320-A,E 7.00:1 140/150 2450/2700 244 lb
O-320-B,D 8.50:1 160 2700 255
IO-320-B,C 8.50:1 160 2700 259
O-360-A 8.50:1 180 2700 265
O-360-F 8.50:1 180 2700 270
IO-360-B 8.50:1 180 2700 270
IO-360-A,C 8.70:1 200 2700 293
LIO-360-C 8.70:1 200 2700 306
TO-360-C 7.30:1 210 2575 343
TO-360-F 7.30:1 210 2575 343
TIO-360-C 7.30:1 210 2575 348

I hope this info helps.
Dave Koopmans (Non-pilot, studying aviation options)

Conclusions?:

Dry Weight Difference = 293 (IO-360-A,C 200hp angle valve) minus 270 (IO-360-B[&M?] 180hp parallel valve) = 23 pounds for 20(+) more horsepower. Not a bad deal in favor of the 200hp engine (almost +1hp per pound). You have to decide if the increased horsepower (mainly better climb performance) is worth the extra $8K (Van's new prices) and 23 pounds.

(Note: Used/Overhauled 200hp engines are usually much better deals, dollar-wise, than brand new ones!)

Good Luck!

Bill Palmer
 
Counter weights?

This has been a very useful thread for me. I am also trying to make the engine decision.

Can someone explain the difference between a counterweighted and a non-counterweighted engine to me? Where are the counterweights, what is their function and what are the advantages/disadvantages?

Regards,

Michael Wynn
RV8 Fuselage
 
Wahooo, how'd I miss this one?

For the original question the REASON that the website doesn't say IO-360-M1B is because the B refers to the ignition type for a Lycoming, and the ignition type is an option on their engines, hence the IO-360-M1 designation (Which lycoming doesn't use, all their designations are three characters in the form (*#*). The first letter * indications power train configuration, the number designates specific modifications to that basic configuration, and the last letter indicates ignition type.

To clarify, the M1 and M1B designations can be used interchangably in this conversation for all intents and purposes.

Now for LOP... wait, I'll shutup now.
 
If money is an object

Bill Palmer said:
I copied this off the Yahoo Lycoming Group:

Re: Engine weights

Conclusions?:

Dry Weight Difference = 293 (IO-360-A,C 200hp angle valve) minus 270 (IO-360-B[&M?] 180hp parallel valve) = 23 pounds for 20(+) more horsepower. Not a bad deal in favor of the 200hp engine (almost +1hp per pound). You have to decide if the increased horsepower (mainly better climb performance) is worth the extra $8K (Van's new prices) and 23 pounds.

(Note: Used/Overhauled 200hp engines are usually much better deals, dollar-wise, than brand new ones!)

Good Luck!

Bill Palmer
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Reputedly, the -M's horizontal induction gets you a couple of HP, so they say 180+. But I'd like to note that the 200's extra horsepower comes out to $400/HP. That's probably a couple hundred hours of gas.
 
Cranks

mlwynn said:
This has been a very useful thread for me. I am also trying to make the engine decision.

Can someone explain the difference between a counterweighted and a non-counterweighted engine to me? Where are the counterweights, what is their function and what are the advantages/disadvantages?

Regards,

Michael Wynn
RV8 Fuselage
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Hi Michael and others,
A counterweighted crank has tuned centrifugal pendulums, commonly referred to as crankshaft counterweights, they provide vibration absorption. The pendulum consists of weights attached to the crank webs in a manner which permits limited movement. When the shaft accelerated under the the action of cyclic torque fluctuations, the pendulum bobs lag behind and counteracts some of the energy imparted by the increased torque. The tuned pendulums on the crank reduce vibration amplitude to almost zero over a wide range of RPM. High compression pistons will change these frequencies. Some or most NON-counterweighted cranks are limited to a certain RPM range and that is why a NON-counterweighted should not be ran at certain RPM's over an extended period of time.

One example is an IO-360A1A 200HP engine with high compression 8:7:1 pistons and a 180HP NON-counterweighted crank, this engine should not be ran at extended periods of time at say 2,350 rpm, it is designed to be ran at say around the 2,450-2,550 rpm range because of the tuning/vibration frequencies. These are only examples and one should contact the engine builder and or Lycoming at recommended RPM ranges and limits.
Every engine has a sweet RPM that it likes to be ran at for smoothness and longevity.

Much of this can be studied in the Sky Ranch Engineering Manual as there are over 50 pages explaining all of this.

Someone tell me if I'm wrong or not, but the last I knew Lycoming is the only manufacture of a Counterweighted crank for the 360's and it is not cheap nor are the rods and rod bolts. The connecting rods are much bigger and the rod bolts are a stretch type bolt. Superior, ECI, etc sells the NON-counterweighted cranks but not the counterweighted.

The main reason I installed the counterweighted Lyco crank in my IO-360 angle valve is because I'm running 10:50 compression pistons and a NON-Counterweighted crank running the compression that high, the engine would not last as long under certain conditions.

My -6 originally had a 180HP crank in the IO-360A1A and after installing the Counterweighted crank I did notice a difference in vibration levels inside the cockpit. The instrument panel with all those $$$$$ :eek: radios and guages don't buzz or vibrate like before. It is very smooth over a wide range of RPM's and I'm very happy with it. I guess it depends on your pocket book and how you want to fly the plane.

Someone chime in with other comments if you see something I stated is not correct.


Hope this helps to explain your questions.
 
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rv969wf said:
Someone tell me if I'm wrong or not, but the last I knew Lycoming is the only manufacture of a Counterweighted crank for the 360's and it is not cheap nor are the rods and rod bolts. The connecting rods are much bigger and the rod bolts are a stretch type bolt. Superior, ECI, etc sells the NON-counterweighted cranks but not the counterweighted.
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What does Superior put on the XP-400? Is it counterweighted? Beefed up? I know next to nothing about the XP-400 and I'm genuinely curious. A little bird told me it's the same form factor as the angle valve Lyc IO-360, but I have my doubts about whether "same form factor" is truly the "same." Somebody once told me that about the IO-390 vs. IO-360-A, and I now know that's not true either.
 
XP-400

dan said:
What does Superior put on the XP-400? Is it counterweighted? Beefed up? I know next to nothing about the XP-400 and I'm genuinely curious.
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I have no idea what crank Superior is using in the XP-400. I guess a phone call to them might answer the question. I'm like you Dan, it'd be nice to know what parts / crank they're putting in those monsters.

The last I knew was that Superior is using "The Thielert Group from Germany" http://www.thielert.com/ to make their cranks and cams, but that's about all I know.








Mar 14, 2006


Thielert Takes Over Superior Air Parts - Profits 2005


Hamburg, Germany, March 14, 2006 - Thielert AG is taking over the PMA and aircraft engine manufacturer Superior Air Parts, Inc. (SAP) based in Coppell near Dallas in Texas, USA. SAP is the world?s leading producer of engine spare parts for small aircraft used for general aviation purposes. The company also manufactures gasoline engines for this type of aircraft. This acquisition will enable SDAX-listed Thielert AG to rigorously expand its range of products in the area of piston aircraft engines too. Currently, Thielert is already market leader in the field of aviation certified jet fuel/diesel, piston aircraft engines. In similar fashion to Thielert, SAP products stand out from others in the market thanks to their high technical quality.

"With its outstanding products and established brand name, Superior Air Parts is the ideal acquisition to help us enhance our market position. Our acquisition of Superior Air Parts marks our final step along the road into the US-American market for engines and engine components and the expansion of our presence there", CEO Frank Thielert said. Agreement on the acquisition of SAP was reached on the evening of March 13, 2006. The value of the transaction is said to be around the 10 million US dollar mark, less than 15 percent of the IPO income earned by Thielert AG last November.

As a so-called PMA (Parts Manufacturer Approval) manufacturer, SAP has been certified for the manufacture of engine spare parts for aircraft engines built by Lycoming and Continental. Moreover, SAP is a leading supplier of replacement engines in the secondary market. The company has just recently launched a piston aircraft engine under the brand name "Vantage Engine", the first one of its kind to have been certified in the USA for fifty years. All SAP products have been certified by the American civil aviation authority FAA (Federal Aviation Administration). Hitherto, the company, which was founded in 1967, belonged to the investment group RSTW.

SAP is a longstanding customer of Thielert in the area of aircraft engine components. Its range of engine components, conventional gasoline engines and innovative CENTURION jet fuel/diesel engines enable the company to cover all needs in terms of engines for small aircraft. Use will be made of SAP?s existing distribution and service channels in the US markets for all products. Furthermore, Thielert will be organising seminars at SAP?s headquarters in Dallas from this March in the maintenance of its CENTURION aircraft engines so that its US customers can also be guaranteed professional service provided locally.

Strong economic performance in 2005 ? course set for further growth in 2006 too

According to the audited year-end financial statements, consolidated sales rose by in excess of 55 percent to a total of 37.6 million euros in the 2005 financial year. In the year of its flotation, Thielert also recorded a significant increase in profits. Its EBITDA improved to 16.1 million euros, around 42 percent up over that of the previous year. Operating profits (EBIT) rose by just under 51 percent in 2005 to total 13.1 million euros. The annual surplus enjoyed even greater growth to end the year up by just under 107 percent at 7.7 million euros.

Thielert?s average workforce also grew significantly in the year under review with a total of 231 employees as compared with 191 in the previous year.
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I want to thank everyone for their input. With your assistance and a phone call to Aerosport I've finally decided on my engine.

My phone call to Aerosport revealed a couple of things that were not mentioned here.

First I asked the difference between the M1 and the M1B and they said they had their own aluminum sump vs Lycoming?s. I?m confident that their options are as good a quality and they are $900 cheaper.

Second I asked them about tappet / roller lifter components. I was told there was no performance benefits and that they were only recommended if I wasn?t going to be flying the plane regularly as they are more resistant to corrosion. That translated into a $600 savings as I will be flying the plane more than enough to prevent corrosion.

Third I told them I was going to be running a FP prop but wanted to order the constant speed engine so that I would have the option to convert over later if I wanted. They told me the FP version also came with a hollowed crank and that it could be easily converted over to full constant speed anytime I wanted. Price difference was $300.

So in a five minute phone call I got my remaining questions answered and to my surprise they actually encouraged me to take the cheaper options for a savings of around $1800. It was great, every time I asked a new question it wasn?t an up-sell it was ?hey if you do it this way you can save some money.?

Gotta give Sue and Bart over at Aerosport a big thumbs up!

So final choice is the IO-360-M2, with 9.2:1 pistons. $24000 for the brand new engine and + $300 for the 9.2:1 piston upgrade is a total of of $24300 for a very nice engine that's low weight and high preformance.

I?m fairly certain I?ll be getting a Catto 3 blade FP prop.

The only thing left to decide is the details of the Electronic Ignition and I?m going to start a new thread for that.

Thanks again everyone for your assistance.
 
rv-8a

i am thinking of the xpio-360 $22,000 to $23,000 but what compresion 8.5 -1 or 9-1 i want the extra 5 hp but if 100ll goes away i dont want problems?
 
That's me - I've already decided I'll have the XP IO360, but I'm thinking 8.5:1 to be able to run 92UL. Match the injectors and use a good multi-probe engine monitor and you can be relatively safe from the detonation gremlin, or at least catch it early. Lower compression will knock me down to 170hp, but we're talking about a 9A here anyway :cool:

Still hoping DeltaHawk pulls it out before it's time for me to order an engine - the fuel system will be built to go either way. 160hp turbonormalized diesel would be DA BOMB baby!
 
<<difference between a counterweighted and a non-counterweighted engine to me? Where are the counterweights, what is their function and what are the advantages/disadvantages?>>

At least part of the problem for engine students is poor nomenclature. "Counterweight" is a lousy term for the device. Yes, I know Lycoming calls them that in the parts book. The whole auto industry calls a viscous damper a "shock absorber" too, but that doesn't make that right either.

When installed in opposing pairs the "counterweights" don't counterweight anything but themselves. Our 4-cyl flat crank engines counterbalance piston and rod mass (imperfectly) with an opposing piston and rod.

In other engines the pendulum may indeed serve double duty as both a vibratory device and a mechanical counterweight. An M14 radial is a good example.

As Alan mentioned, they are actually tuned centrifugal pendulums. If you're really curious, head for the library and look them up under "Sarazin pendulum" or "Chilton pendulum" or "bifilar pendulum".

Note that Lycoming pendulums are located at the accessory end of the crank, meaning as far from the propeller end as possible. The amplitude of a torsional vibration (degree of twist) is of course greater as you increase distance from the vibrational node. The F1 node in our direct drive crankshaft-propeller system is right behind the prop hub. Placing the pendulums at the far end makes them more effective.

It's important to realize that a bifilar crank pendulum is tuned to a particular engine order, not a frequency. "Order" in this context means "number of times an event happens per revolution" (a one-per-rev event is 1st order, six per rev is 6th order, every other rev is 1/2 order, etc). For example, if the operating range is 700 to 2700 RPM and you have a 6th order pendulum, it has the potential to reduce 6th order amplitudes across a frequency range of RPM x Order, or 4200 to 16200 hertz. The wide effective frequency range is why engineers got so excited about the system way back in the 1920's (or was it the 30's?)

Why do you want them? A pendulum absorber causes a dramatic reduction in vibratory amplitude at it's tuned order. In simple terms, that is one less vibe available to beat up your engine components and propeller. As a personal preference, I want them unless I'm running an engine with low BMEP.
 
Same thought

On my long cross country (for me) I was sitting there about 100F LOP smiling at my 295 to 305F CHT's and wondering how long my cylinders would last...Hopefuly forever in that mode?...:)

Another thing that I finally realised, it there is quite a bit more efficiency to be had when the throttle is all the way in...I.e at 8000 or above.

Frank
 
Just to compare $$$ my engine total cost $18781,ECI kit engine ,9:1 pistons,Lyc forward sump, spark plugs and break in oil from AERO no shipping charge because we are buying two engines,AFP F.I.,LASAR ignition,starter and alt from others but included in total cost. I still need oil cooler and hoses.
 
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