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Prop for ECI IOX-340 Stroker

rickmellor

Well Known Member
I've been bouncing back and forth on which engine to put in my 7A and have a strong interest in ECI's 340 stroker. Can anyone who's running this engine post which propeller you're using and your impressions of it?

I've got two choice props in mind that seem like they'll work:

1) Hartzell BA (C2YR-1BF/F7496-2), 72", 180HP
2) Whirlwind 200 RV

The Hartzell is my preferred prop but I'm pretty certain that if I ask them if it'll work with this engine they'll say no because they haven't tested it. If I ask the Whirlwind guys (they don't seem to answer emails) they'll probably say "no problem".

What to do, what to do...

-Rick
 
Prop

Very unusual that you can't get through to Whirlwind. I'd call. They have a human answer the phone and can direct you to someone to answer the question.

I have a WW 200 RV and love it. I did have a seal failure at 55 hours that was apparently installed improperly. I was taking the plane out of service for paint so it wasn't a big deal. Later I had my spinner bracket crack (as most have, prior to the fix). They were extremely responsive and developed a fix. All seems good.

I'm very happy with the prop. It is very smooth and performs quite well.

I know this doesn't directly answer your question but I believe the WW prop would be a great match for this engine.
 
Darwin, which engine/plane do you have the Whirlwind on? Also, how many hours have you had it in service? I'll give WW a call on Monday to talk about this. I emailed them last week (I'm an Internet junkie so it's always my first option) but didn't get a response.

My main concern with the WW is that on the 7A with the IO-340 I'll not have enough weight up front. However, if I put the batteries on the FW then it should be fine.

-Rick
 
Hatzell BA prop should be OK, w/ caveat

rickmellor said:
I've been bouncing back and forth on which engine to put in my 7A and have a strong interest in ECI's 340 stroker. Can anyone who's running this engine post which propeller you're using and your impressions of it?

I've got two choice props in mind that seem like they'll work:

1) Hartzell BA (C2YR-1BF/F7496-2), 72", 180HP
2) Whirlwind 200 RV

The Hartzell is my preferred prop but I'm pretty certain that if I ask them if it'll work with this engine they'll say no because they haven't tested it. If I ask the Whirlwind guys (they don't seem to answer emails) they'll probably say "no problem".

What to do, what to do... -Rick
I would not assume they say no, in fact the 320 is easier than the 360 on props. It's possible they may give you positive indication that its OK. However you are right they don't KNOW 100% for sure unless they test it. If there is enough IO340's they will test them, may be on your plane if you volunteer.

I think a possible show stopper or at least detail could be the crank pattern or bushing size? The 320 takes a C2YL hub? The C2YK and C2YR hub goes on the 360.

K hubs - have six, 1/2" bolts on 4-3/4" circle and four 3/4" drive bushings

R hubs - same as K but has five 3/4" drive bushings

L hubs - similar to K hub but uses 7/16" bolts and 5/8" drive bushings


So you may(?) need to change the bushings may be not? I don't know what kind of crank flange they install on the IO340X, but I assume it will be more in line with the 320's "L" hub, but if you had a choice, you may want them to install the 360 "R" bushings. Of course the (I)O320 prop Van sells is the C2YL-1BF/F7663-4, I am sure that would fit.

Call or email the IO340 manufacture and Hartzell, ask them what they think.

I would could see being comfortable with a BA prop for the 360 on a 340. As you probably know 320's tend to have NO rpm or restrictions of any kind with hartzell's. Why? Well the 360 (with out dampened crank) is a bit of a brute in the power pulse department. I don't know much about the 340 but its 170HP and the extra 10HP is from longer stroke, I think. That should not be any more hostile vibration wise than a 360 with Hi Comp pistons or electronic ignition, my guess. The BA prop is approved for 360's with EI with some small point limitations.

The TRUTH is anything other than what's tested is a guess. Right now Hartzell has tested the HC-C2YK/F7666-2 -4 and C2YR-1BF/F7496-2 or -4, on 360's with electronic ignition and FADEC, on RV's. The airframe is included because airframe can have something to do with prop vibrations, so it's best to test the whole combination.

The worse possible case, 360, un-dampened crank, electronic ignition and/or hi-comp pistons with the older Hartzell C2YK/F7666. The BA is better than the older C2YK/F7666, even with EI. It has no "range" of stay out RPM or life limit, just a point power settings to avoid which does not affect normal operations.

The unknown of the 340? You really need to call or write them. I can assure you Hartzell will get back to you. Hartzell can't approve or disapprove the 340 unless they have tested it. I find they don't get real excited about much, like Oh My Gosh! Its a little more subtle, and has to do with fatigue life. They want infinite fatigue life and very large margins. My feel is they will not get too excited and tell you to be cautious. If you use a combo of C2YK/F7666 and the C2YL/F7496 restrictions, it will have minor or nil affect on you operationally. IT's probably not necessary but it's something to consider.

My advice is use the most conservative restrictions or combination of the most conservative restrictions until a 340/Hartzell test is done, which no doubt will be done at some point down the road, especially if the engine becomes popular. The BA prop has now been tested on the IO390 angle valve. It took time because they work on the more popular engines first. I asked Hartzell how much it would cost to do a vibration test on an individuals plane? $25,000 to $50,000. I bet if the 340 is popular they will test it at some point on their nickle.


I'v talked to Hartzell's engineering a few time about this general topic, engine mods and prop limitations. For example Hi comp pistons. All you high compression piston operators with Hartzell's are in the same boat as the 340, there is no test data. They have NOT tested hi comp pistons, but its assumed it has similar effect as electronic ignition.

May be the 340 engine manufacture will work with Hartzell and pay for it? It all depends on how many they sell.

As far as the other brands? Who knows what test they are doing. Wood cores tend not to be critical; "God's Composite", aka wood tends not to be fatigue critical and dampens vibes well. However again, if not tested ON THE AIRFRAME with your exact engine config, piston, ignition and so on, than its an unknown. Whirl Wind? I don't know. I got the feeling they did not do vibration surveys. I could be wrong. They used McCauley hubs (and think still do) with their blades. Not sure if they are wood core? Again composites are pretty good in fatigue and vibrations, but there's NO guarantees unless a vibration survey is done.


Hartzell can't test every little engine mod experimental guys and gals throw out there. IF you have a stock 320 or 360, you're covered. A 320 or 360 with EI or FADEC, they have data and are covered. However these new 340's and high compression pistons, you kind are in a fuzzy area.

Overall you Hartzell has very high standards and safety margins. There goal or going in postion is infinite fatigue life. Unlike helicopters most GA planes rarely have "Life Limited Parts". I suspect the 8,700 hour limit on the C2YK/F7666 on 360's, with EI, is conservative. Besides flying 150 hours a year, 8,700 hours is 58 years. Also most metal blades eroded at some point from sand, gravel on takeoff and rain in flight. Still the LIMITATIONS do not severely affect the utility.

If you get a BA prop, it should last a life time and be very safe. The only other down side is it may not be perfectly optimal, since its made for a +180 HP engine, but it should be better than the prop made for the 320. That would be a good question to ask Hartzell.

If you go with a boutique small company like whirlwind or aerocomposites, there is no guarantee you will not have problems. Even if they eventually return your calls and say "no problem". (Note: if you can't get a returned call, what do you thing repair and service is like?)

Hartzell just happens to KNOW the limitations. Just because there are no limitations published on the other brand props, which have not been in service very long, does not mean there's no gotchas out there. I would go Hartzell my self, less expensive, better performance and better support.
 
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Thanks George!

I was hoping you would chime in here, George. You always bring up good points.

A bit more info on the engine I'm eyeing: The IOX-340 has a 9.0-1 compression and I'll have one Slick mag and one Lightspeed II EI on it. It'll use ECI's cold air induction and their fuel injection. This configuration is rated at 185HP and the weight should be equivalent to an IO-320. As far as the prop flange goes, I hadn't asked but I think I read somewhere that it's the same as the 360's because of the higher HP. Something to confirm ...

I'd asked ECI about propeller choices and they suggested that I talk to the engine builder for that (America's Aircraft Engines). These guys were very helpful with the engine but I didn't get what I was looking for in terms of prop recommendations. They may not be the best source anyway and I'm sure my questions were not direct enough. I'll call Hartzell and WW next week and get the skinny from their perspectives.

-Rick
 
Perhaps a stupid question, but since the 7A's tend to be tail heavy, isn't the wieght savings of the IO-340 a bit of a contradiction to logic? And by the same token doesn't putting a composite prop on it make it that much worse not better? I would think that if you had a IO-340 with the WW prop, you would have severely limited baggage capacity.
 
CG

isn't the wieght savings of the IO-340 a bit of a contradiction to logic?

Well, that's a great argument for the Hartzell which is also part of the reason I prefer it over the WW ... not to mention the other benefits of cost, maintainability, etc.

The great thing about this engine is that it saves weight without compromising on power. The net result being that you have more flexibility for dealing with CG issues. I will have dual batteries (all electric, IFR) and I can put them both on the FW to help offset the CG issues.

Worst case some ballast can be added to get things in line while keeping the plane as light as possible. In all I think this approach is much more sensible than going the other route and putting more power and weight than the plane is designed for up there. The 390's and the Subie H6's are, in my opinion only, going the wrong direction.

-Rick
 
rickmellor said:
The great thing about this engine is that it saves weight without compromising on power. The net result being that you have more flexibility for dealing with CG issues. I will have dual batteries (all electric, IFR) and I can put them both on the FW to help offset the CG issues.

-Rick
I do not see a weight savings. At least not enough to make up for the weight of a battery.

According to:
http://eci2fly.com/exp/eng_comparisons11x17.pdf

Engine HP Weight
O-320 160 270
O-340 177 277
IO-340 185 280
O-360 182 282
IO-360 188 285

With 1,969.5 hobbs hours on my -6, I am thinking of coverting my existing NARROW DECK to the 340 crank and Cold Air FI. I want the 360 but do not have the cash for it. I have the cash to add the crank and FI at overhaul.

I saw George's post about props. When I talked to ECI at Van's Homecoming, they said that the crank could be configured for the 360 or 320 Hartzell props. If you check their price list, http://www.eci2fly.com/exp/price_list_exp.aspx , there are no less than 7 different crankshafts for the 340.

Sorry to break your bubble.
 
ECI I0360

Hey Rick,

I have the ECI I0 360. Just curious as to why you want the 340. As Gary pointed out the weight savings is somewhat minimal.

The 340 can be configured with the flange you need. Don't think this is a big deal.

I don't think you'll be able use the Hartzell until they do some testing. That leaves you with one less option. Maybe they will have tested when you are ready.

Whatever you decide, be sure you take lead time into consideration when ordering.
 
Gary & Darwin, maybe I missed the boat on this one. Is the 340 targeted at conversion customers? When I read through ECI's stuff I was expecting more savings.

I haven't compared ECI's 340 and 360 yet just the 340 to Superior's XP-360. In this comparrison you gain 5hp with the 340 and shed 10 lbs. That started to seem pretty compelling to me so I wanted to complete the picture of the 340 on my plane ... hence this thread. I still have 3-4 months before I shell out the cash so I'm trying to understand the options.

Btw, American Aicraft Engines said about six weeks lead time (seemed shockingly short to me).

-Rick
 
Rick, that's slow :) I got my ECI kit in one week.. sounds like they're taking 5 to build it hehe..

On a more serious note, shedding pounds off of -7A's nose isn't really the best place to save weight. If you can loose some in the tail area, that's be a lot more useful, even if total weight loss isn't as much.
 
AAE said it would be 1-2 weeks for the parts from ECI and 1-2 weeks to put it together depending on their work load at the time. Then it needs to ship from Tulsa to the Bay Area so another week or so.

I'm shocked by this because when I talked to Superior their quoted lead time was about 12 weeks. Considering that it took 8 weeks to get an AP from Trutrak and Eggenfellner's next batch of Subies are available for August next year .... 12 weeks seemed pretty good to me. :)

Btw, you guys are doing a good job of making me think more about the ECI 340 vs. their 360. If the weights are nearly identical and the power is about the same then one would probably be better off with the 360 because then you're not strapped to a single source for parts (crank).

I do know that since I live on the coast I definitely want ECI's cylinders because of corrosion resistance. (now that I've said that someone will tell me that ECI's rust worse than any others out there!!)

-Rick
 
rickmellor said:
I do know that since I live on the coast I definitely want ECI's cylinders because of corrosion resistance. (now that I've said that someone will tell me that ECI's rust worse than any others out there!!)

-Rick
Rick:
I am only an A&P and DAR. From what I know, the NEW ECI cylinders are the best rust resistance cylinders you can buy at this time.
 
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