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-   -   RV-14 Engine choice (https://vansairforce.net/community/showthread.php?t=98748)

A6M 03-22-2016 06:05 AM

What about that new diesel the E-300 few details but looks good for the RV10 I am looking at options now

jenatepilot 04-06-2016 08:18 PM

I've Spoken with Kevin on this engine. I'm watching it carefully myself. Might be amazing

mike newall 04-06-2016 11:47 PM

To bring this back onto thread...

At Sun N Fun.

The after market engine chaps are all over the 14 !

They know that it needs a forward governor, which, for an IO-360 angle valve motor is a little unusual.

There are options around from JB, Aerosport etc etc

The thing that these chaps said was - if you have a 390, the only place you can get spare is from Lycoming. Good point !!

We will see how the market develops, eh ?

czechsix 04-08-2016 06:41 PM

Quote:

Originally Posted by mike newall (Post 1068680)
There are options around from JB, Aerosport etc etc

The thing that these chaps said was - if you have a 390, the only place you can get spare is from Lycoming. Good point !!

And because the only place you can get a spare IO-390 cylinder is from Lycoming, the price is eye watering. I started out thinking I wanted a 390 until I was told by Barrett that a new 390 jug is $4800. No competition, so Lycoming really jacks up the price (apparently not considering the fact that people like me are deterred from buying their engine altogether because I care about long term operating costs). Superior's XP-400 makes 5 more HP and one of the benefits they pitch are that their cylinders are $2800. However, as the pilot population continues to decline I wonder how long there will be a big enough market to support more than one engine manufacturer, and if I had to bet on one being there 10-15 years from now I'd have to bet on Lycoming. So pick your poison...the 390 vs 400 choice is a mixed bag from a long-term support perspective.

There's a lot to like about an overhauled angle valve IO-360 with 10:1 pistons. Initial investment is much lower, parts are readily available and relatively affordable, it will make approx the same HP as the 390, and it will be more fuel efficient to boot. You can't burn mogas, but then again you can't burn mogas in the 390 or 400 either, so you might as well take advantage of the compression increase to boost efficiency. I talked to a lot of engine shops at Osh and the general consensus seems to be that the IO-360 can handle the 10:1 pistons without significant reliability concerns for normal flying. There are already a number of experimentals flying 10:1, Firewall Forward has an STC for Mooney's & Cardinals that's been around for a while, and Lycoming has the HIO-360-D1A with 10:1 pistons (used in helicopters). The only cautions I heard were that if you are going to run them hard (wide open at low altitude for extended periods of time for racing or acro), you may eventually experience accelerated bearing wear or case fretting that could require teardown before reaching normal TBO. But that kind of abuse is hard on any engine and not my mission for the -14.

One factor to keep in mind for those planning on the Hartzell is that you'll need a counterweighted crankshaft if you use 10:1 pistons. I plan to go with Whirlwind composite which doesn't require the counterweights.

Honestly I'd be pretty happy with a stock 200 HP angle valve IO-360 like Vans has in their -14 demo bird, my biggest hesitation is with respect to resale value. In the RV-6/7/8 series, it seems that buyers will pay a pretty good premium for O-360 vs 320, and that was part of my justification for putting a 360 in my -8A. Doubtless buyers will pay more for a -14 with a 390 in it, but the real question is whether the difference in market value of a -14 powered by a new 390 vs an overhauled 360 will be greater than the difference in up-front cost to purchase these engines...

Av8rRob 08-03-2016 10:59 PM

Did anyone learn anything new and exciting about engine options for the -14 at Oshkosh this year?

jeffw@sc47 08-04-2016 04:41 PM

I am not an engine savvy builder and it's still too early for me to be making a deposit, but I am looking around; the Titan IO370 angle valve has caught my attention. And now that Titan is a subsidiary of Continental, they may be a good option regarding long term support.

Bigortho 08-06-2016 06:50 PM

Titan IO-370
 
I'm building my 14 at Synergy Air in Eugene, OR. Several other builders have purchased the Titan IO-370, both to save money and get modern jugs. However one buyer's engine arrived with the wrong data plate attached and nuts fixed with torque seal, but not properly torqued (loose as a matter of fact).

He could not get satisfaction from Titan nor get them to honor their warranty. While he had an engine mechanic inspect his engine and had all external nuts re-torqued - he does not trust that internal specs were met. He is very unhappy.

jswareiv 08-07-2016 10:08 AM

Quote:

Originally Posted by Bigortho (Post 1101131)
I'm building my 14 at Synergy Air in Eugene, OR. Several other builders have purchased the Titan IO-370, both to save money and get modern jugs. However one buyer's engine arrived with the wrong data plate attached and nuts fixed with torque seal, but not properly torqued (loose as a matter of fact).

He could not get satisfaction from Titan nor get them to honor their warranty. While he had an engine mechanic inspect his engine and had all external nuts re-torqued - he does not trust that internal specs were met. He is very unhappy.

If you are looking to customize your engine, whether it's a 360 or 390, check with Ly-Con. Great product, great reputation and their customer service is 2nd to none. I didn't know the first thing about what I really needed in an engine and they spent a ton of time helping and educating me. I think they were very fair and didn't oversell me on things I probably didn't need. My requirements were, what can I do to get the most bang for my buck for speed and economy. On the Dyno, it tested out at 235HP and at 8,000' 173kts, burning 9.6GPH. Specs of what they did are on my blog.

jswareiv 08-07-2016 12:10 PM

Website
 
I just found out that GoDaddy is serious about wanting you to pay to renew their hosting. Apparently, I ignored them, so they shut it down. It's fixed and they got their money. Sorry.

salto 08-07-2016 04:39 PM

Thanks for access to your build site Stoney.
Very nice paint scheme?

jswareiv 08-07-2016 05:14 PM

Quote:

Originally Posted by salto (Post 1101331)
Thanks for access to your build site Stoney.
Very nice paint scheme?

Thank you, 2 more weeks and I fly to Ft. Worth to pick it up, can't wait!

rvbuilder2002 08-07-2016 06:18 PM

Quote:

Originally Posted by jswareiv (Post 1101237)
If you are looking to customize your engine, whether it's a 360 or 390, check with Ly-Con. Great product, great reputation and their customer service is 2nd to none. I didn't know the first thing about what I really needed in an engine and they spent a ton of time helping and educating me. I think they were very fair and didn't oversell me on things I probably didn't need. My requirements were, what can I do to get the most bang for my buck for speed and economy. On the Dyno, it tested out at 235HP and at 8,000' 173kts, burning 9.6GPH. Specs of what they did are on my blog.

This is not intended to Dis Stoney regarding the choices he made on his engine.... just pointing out that you don't necessarily have to pay for special extras to get good performance.

I have flown the RV-14A demonstrator on a couple of trips getting equal or better speed/ fuel flow (the tri gear should technically be just slightly slower).

It will easily true out at 171-172 Kts at 8.3-8.5 GPH at 9500 '

It has a bare bones stock IO-390.

MLock 08-08-2016 03:42 AM

Stoney is obviously a talented and well thought out builder, but I have to chime in with Scott. On my way to OSH this year, N914VA had a TAS of 175Kts, 8,500', 10.2 gph at peak EGT. Again, a stock I0-390.

After an enlightening conversation with Scott about LOP operation, I will begin to experiment and see how I can fine tune engine operation.

jswareiv 08-08-2016 07:02 AM

Quote:

Originally Posted by MLock (Post 1101406)
Stoney is obviously a talented and well thought out builder, but I have to chime in with Scott. On my way to OSH this year, N914VA had a TAS of 175Kts, 8,500', 10.2 gph at peak EGT. Again, a stock I0-390.

After an enlightening conversation with Scott about LOP operation, I will begin to experiment and see how I can fine tune engine operation.

Thank you Mitch for the compliment. However, I am a first time builder with absolutely no prior experience. I made most of my choices from other's experience and research. Scott has forgotten so much more than I will ever know and respect him immensely. So... I must be doing something wrong. Once I get the plane back from paint, and I get the 100 hours on it, I will again check the numbers and report back. If I understand the power equation, if all else is equal, the increase in HP should result in faster speeds, however, the GPH may be higher. Once I am confident I am doing everything correct, to get the most accurate readings, I will report back. I have checkers in the new paint scheme, so that should get me at least 5 MPH. :)

rvbuilder2002 08-08-2016 09:07 AM

Since I don't have any recent cross country flights, and since my memory isn't what it used to be, I decided to double check my self.......

Here is a post (first post in the thread) from a couple years ago showing that my stated fuel flow was off a little bit but not much. Still good speed vs Fuel flow #'s with a stock engine.

http://www.vansairforce.com/communit...d.php?t=119114

Tom Martin 08-08-2016 09:46 AM

I have just gone through an engine change on my Rocket. Not an RV but I now have a good comparison of High compression (10:1), and flow matched cylinders to a totally stock lycoming engine.
I had 930 hours on my original engine and had had the ECI cylinders off three times due to ring delimitation. The last time the engine never broke in and after 60 hours of blow by my engine started to make metal. An inspection showed a spalled cam that had been perfect prior to the last cylinder replacement.
While tearing the engine down excessive crank bearing wear was evident. Was this caused by the high compression pistons or wear induced by the products of ring blow by? Probably a little of both, I had known that TBO would be reduced using the HC pistons but had hoped for at least 1500 hours not less then 1000.
I decided to use brand new stock Lycoming jugs on the rebuild.

After 60 plus hours on this rebuild I can say that I have lost 5 knots in cruise and burn about 1 gallon more per hour at rich of peak settings. The ECI jugs did not seem to like LOP operations and the speeds dropped way off to the point that I did not feel there were any real savings in terms of time or fuel with LOP settings.

With the new jugs I can run quite nicely LOP and after a few nozzle swaps I have all cylinders peaking within 0.1 gph, a number I have never gotten close to in all my other aircraft. The engine runs very smooth and I am experimenting with increasing power levels running LOP and there is some promise that I am going to get my fuel economy back. I am afraid that that extra 5 knots is gone for good.
The engine is broken in and oil consumption was one quart in 30 hours which is quite an amazing difference from the ECI jugs. At the end of the 30 hours the oil still has a gold tinge to it!

I have no regrets regarding the HC pistons and the flow balancing. At the time I was serious about racing and my numbers were very good. It came at a price in terms of longevity but money spent, I will forget, race wins I will not.
It is too bad that I had not gone with the Lycoming jugs from the start but at that time, 12 years ago, I had had some issues with lycoming quality and ECI had these new jugs that promised corrosion resistance. Since that time competition has upped the Lycoming quality and we all know how many folks have had issues with ECI jugs. It would indeed be interesting to see how HC pistons and flow balanced Lycoming jugs would have done.
At this time I am very happy with my stock engine; there was always this little black cloud in the back of my mind while flying the non stock engine, especially in areas of rugged terrain!

jswareiv 08-08-2016 01:05 PM

Quote:

Originally Posted by rvbuilder2002 (Post 1101473)
Since I don't have any recent cross country flights, and since my memory isn't what it used to be, I decided to double check my self.......

Here is a post (first post in the thread) from a couple years ago showing that my stated fuel flow was off a little bit but not much. Still good speed vs Fuel flow #'s with a stock engine.

http://www.vansairforce.com/communit...d.php?t=119114

One last bit of clarification, I wasn't recommending against the stock engine, I said in my post "if you are looking to customize it", they should also speak to Ly-Con. They have a great reputation.

rvbuilder2002 08-08-2016 01:52 PM

Quote:

Originally Posted by jswareiv (Post 1101566)
One last bit of clarification, I wasn't recommending against the stock engine, I said in my post "if you are looking to customize it", they should also speak to Ly-Con. They have a great reputation.

No problem..... I didn't read it that way.

And I am not specifically recommending against modified engines either.

Just pointing out that the performance you have reported with an engine that is supposed to have an additional 25 HP is not better, and if anything worse (because of fuel flow) than RV-14's that have bone stock engines.

Flywade4 09-27-2016 09:03 PM

IO-360 from a 177RG
 
Quote:

Originally Posted by Mike H (Post 1010977)
The Aerosport IO-382 is a PARALLEL VALVE engine. The IO-390-A3B6 and IO-360-A1B6 are ANGLE VALVE engines. I see where lots of -14 builders, or potential builders talk about this engine being an alternative. It can be an alternative if you are willing to modify the baffeling and other parts FWF to make it work. For the $1000-$2000 "savings" vs the IO-390 I am not sure it is worth it.

If you really want to build a -14 on the "cheap" I would look for a serviceable angle valve IO-360 from a Mooney or a C-177RG.

I have a Low time IO 360 in my 177RG that I want to use, What do I need to know?

SabreFlyr 09-28-2016 09:14 AM

Quote:

Originally Posted by Flywade4 (Post 1114821)
I have a Low time IO 360 in my 177RG that I want to use, What do I need to know?

I'm thinking that there is a basic list of the required specs in this thread but I didn't find it from a brief scan. IIRC, you need an angle valve IO-360 (mostly because of CG issues, I believe), with horizontal induction & forward governor. Don't quote me, but I believe that the 177RG engine meets those specs. It's an -A1B6D, correct? Just need to know how that differs from the -A1B6.

kaber56 09-28-2016 10:33 AM

Make sure it is an A1D6. The A1B6 as in the C177RG does not have a front governor pad. The engine MUST have a front governor pad (if you are going to be using a constant speed prop).

SabreFlyr 09-28-2016 11:04 AM

Quote:

Originally Posted by kaber56 (Post 1114915)
Make sure it is an A1D6. The A1B6 as in the C177RG does not have a front governor pad. The engine MUST have a front governor pad (if you are going to be using a constant speed prop).

That's confusing! It's my understanding that the IO-360-A1B6 that Van's sells, and used in the -14 prototype, has the front governor pad. The following Wikipedia page (which could ABSOLUTELY be wrong) indicates that the -A1B6D used in the 177RG differs from the -A1B6 only in the type of mag:

https://en.wikipedia.org/wiki/List_o...ariants#IO-360

(And, I'll sheepishly admit that it was another Wikipedia page that I used to determine that the 177RG uses the -A1B6D. :o)

EDIT: Okay, I think I must have referenced an incorrect post that it was the -A1B6 in the -14 prototype. The Wiki page I reference above also indicates that it's the -A1D6 that has the front governor, not the -A1B6. At the same time, I've seen multiple references to the IO-360 from the Mooneys and Cardinal RGs being suitable engines for the -14/-14A. And, more hearsay, that the IO-390 being used to re-engine those same airplanes. I bow out of the discussion now. I'm obviously passing on too much bum info! :o

pazmanyflyer 09-28-2016 12:31 PM

Quote:

Originally Posted by Flywade4 (Post 1114821)
I have a Low time IO 360 in my 177RG that I want to use, What do I need to know?

Straight from Vans on their FB page.

"One of the most important red flags is the location of the propeller governor. The IO-360-A1D6, like the IO-390, has the governor mounted on the front left side of the crankcase. Many, probably the majority, of IO-360s have governors mounted on the rear accessory case, where it physically interferes with the steel engine mount/nose gear of the RV-14A and causes many ducting/wiring/routing problems for the RV-14. From what we can tell, it is not feasible to convert a rear governor engine to the forward governor configuration. We recommend that RV-14 builders avoid IO-360s with rear-mounted governors."

The full version here: https://www.facebook.com/permalink.p...21827541221519

Bigortho 01-07-2017 12:03 PM

RV Engine Choices
 
Van?s Forum is filled with pages of discussion about which engine to buy, because builders want either a cheaper engine or a more modern engine than the Lycoming IO-390 sold by Vans. I too have been tempted by either the Titan 370 or the Superior XP-400 because they are advertised as being more advanced than the IO-390 as they come equipped with Nitrided Cylinders, counterbalanced crankshafts, roller tappets, weight matched components (pistons, rods, etc) and burn premium grade ethanol free mogas.

In addition Superior and Titan would let you build your own engine in their engine school, which would enable you to maintain it. However, after Continental bought Titan, they did away with engine school, but Superior will still allow you to observe or assist your engine build. Both engines are significantly cheaper than Vans Lycoming.

There are many arguments against using these alternative engines. The Titan attaches it?s constant speed propeller governor on right rear pad, where it interferes with the engine mount. In addition the Titan weighs 25 pounds less than the IO-390, which can lead to center of gravity problems. People who have installed the Titan report that expenses of modifying the firewall forward package have eaten their cost savings. The Superior engine is 2 inches longer than the IO-390, which will result in interference with the fit of the cowl. Lastly mogas isn?t a realistic fuel alternative as finding it when flying cross country is nearly impossible.

As for engine school, Lycoming offers both engine maintenance and engine assembly/disassembly courses, which will enable you to maintain your engine.

All this Sturm und Drang has been caused by Lycoming?s awful website, which offers little information and specifications. You can?t even find Lycoming?s publication Certificated Aircraft Engines SSP ? 110 on their site. You can download the June 2010 version here:

http://www.readbag.com/lycoming-supp...sources-ssp110

Now the good news: I need not have been concerned about IO-390?s modern features. After speaking with Lycoming?s technical support I learned that the Lycoming IO-390 engine has all the advanced features that we need. Vans sells the Lycoming model XIO-390-A3B6 RT, which comes with nitrided cylinders. A3B6 RT indicates that the governor is mounted on the left front of the engine, the propeller flange bushings are reindexed, the crankshaft counterbalanced with 1/6 & 1/8 order counterweights and the push rods have roller tappets.

If you want polished ports; pistons, pins & connecting rod?s all weight matched to 1/2 gram: order the Thunder Bolt version of the IO-390, which starts at $39,700. You can substitute E-Mags for the magnetos for an additional charge of $2,400. As for me, I plan on purchasing the IO-390 from Vans as soon as Lycoming announces it?s Sun ?n Fun show price.

Hartzell's composite propeller costs twice as much as it's 74 inch IO-390 aluminum propeller. As opposed to the 360, the aluminum propeller has no RPM restrictions when running on the 390.

See chart on next page: 


Engine Comparison


Manufacturer Lycoming Superior Titan
Designation XIO-390-A3B6 RT XP-400 IOX-370-A4H1N

Bore (inches) 5.319 5.126
Stroke (inches) 4.375 4.375
Displacement 389 400 361
Length (inches) 30.7 32.8 29.07
Width (inches) 34.25 34.3 33.41
Height (inches) 19.35 24 24.8
Dry weight (lbs) 308 310 283
Mount Dynafocal-1 Dynafocal-1 Dynafocal-1
Fuel system Injection Injection Injection
Fuel type 100LL 100LL/Mogas 91 100LL/Mogas 93
Cooling system Air Cooled Air Cooled Air Cooled

Power at 2700 rpm 210 215 200
Specific pwr: hp/in? 0.54 0.54 0.55
Compression ratio 8.70:1 8.90:1 9.6:1
Pwr/weight: hp/lb 0.68 0.69 0.71

Cost 38,700 34,500 30,300

Prop Governor Front Left Right Rear

Av8rRob 07-28-2017 10:45 AM

Any engine updates at Oshkosh '17?
 
Just curious if anyone learned anything new about our -14 engine options at Oshkosh?

Thanks

czechsix 07-29-2017 06:19 PM

Quote:

Originally Posted by Av8rRob (Post 1191145)
Just curious if anyone learned anything new about our -14 engine options at Oshkosh?

I spent all week at OSH and if there's anything new with respect to engines suitable for the -14 I didn't hear about it. Van's is running the usual show special on IO-390 with Hartzell metal prop. It's not clear whether that deal is negotiated by Vans or between Lycoming and Hartzell, but I sure wish they'd offer a Lycoming/Whirlwind combo so we could get a modern composite prop. The Hartzell is the cheapest but it's heavy, transmits lots of vibration back into the airframe (typical of any metal prop), and worst of all the blade hub seals tend to dry out if you don't get it flying soon enough and then you've gotta pull the prop off and have it torn down to replace them. Kiss your $1000 savings goodbye...been there, done that, and Hartzell shows no inclination to fix the issue even though they've known about it for decades. So...the bundled deal is the cheapest option up front but has its drawbacks unfortunately...

Carl Froehlich 07-29-2017 08:39 PM

Quote:

Originally Posted by czechsix (Post 1191403)
SNIP but I sure wish they'd offer a Lycoming/Whirlwind combo so we could get a modern composite prop. SNIP...

Considering the Whirlwind 650 hour/5 year teardown and cost, I offer the Hartzell is the better value. I have a lot of hours behind this prop in the RV8A and RV-10, and my third Hartzell BA prop just arrived for the new RV-8 project. I've never had any issues with hub seals or anything else.

Carl

rwtalbot 07-29-2017 09:02 PM

Quote:

Originally Posted by czechsix (Post 1191403)
I sure wish they'd offer a Lycoming/Whirlwind combo so we could get a modern composite prop.

For most of us the Hartzell prop sold by Vans provides the best performance, is more durable and costs the least to buy and own.

Whirlwind have significantly higher overhaul requirements. Depending upon the model the Whirlwind gives you 3-5 years and between 400-650 hours. There are quite a few reports of premature failures - loose blades, grease leakage etc. In Australia we get 10 years and 2,000 hours on Hartzell even on a certified aircraft. One of the main reasons is that the Harzell can be re-greased at annual.

No composite blade will do well with stone damage. They cost lots of money when the nickel leading edge gets cracked and you will be out of action until it is repaired. Not ideal on an -A model RV with limited ground clearance. Taildraggers tend to do better.

Of course, the composite props are lighter, produce fewer vibrations and are great for aerobatics where the gyroscopic forces are low. They are quieter for our friends in Europe. Is it worth the additional inconvenience and cost for a composite propeller? That's up to each builder.

czechsix 07-29-2017 09:09 PM

Quote:

Originally Posted by Carl Froehlich (Post 1191426)
Considering the Whirlwind 650 hour/5 year teardown and cost, I offer the Hartzell is the better value. I have a lot of hours behind this prop in the RV8A and RV-10, and my third Hartzell BA prop just arrived for the new RV-8 project. I've never had any issues with hub seals or anything else.

If I recall correctly Hartzell has a TBO of something like 6 years but I've never met anyone in either the experimental or certified world who actually does that, and neither do the Whirlwind owners. As for the issues with slinging grease on the Hartzell, it's well documented by many owners, I think Tim Olson has written about it in his blog and plenty of instances in the VAF and Matronics forums. I suspect you are getting your airplanes flying more quickly than the average homebuilder if you've had three of them and no problems so far...

czechsix 07-29-2017 09:22 PM

Quote:

Originally Posted by rwtalbot (Post 1191432)
Whirlwind have significantly higher overhaul requirements. Depending upon the model the Whirlwind gives you 3-5 years and between 400-650 hours. There are quite a few reports of premature failures - loose blades, grease leakage, etc

Are those failures on recent 200RV and 74RV models? I know there were some issues like that with the earlier WW 151s about a decade ago but thought those problems had been resolved. If not it looks like I'll have to pick my poison when it comes time to buy a CS prop for my -14...

Av8rRob 07-29-2017 09:35 PM

Mt 3 blade
 
Since this thread is turning into a prop discussion, what are the thoughts about using a MT 3 bladed prop. I think I remember the weight is 55lbs so it is more inline with the Hartzell. That should help with cg issues. Besides the 12,500 price any other issues?

redbaron 07-29-2017 10:20 PM

Viking aircraft engines
 
Take a serious look At the new Viking engines they have been upgraded and include some with turbo charging.

czechsix 07-30-2017 10:53 AM

Quote:

Originally Posted by Av8rRob (Post 1191440)
Since this thread is turning into a prop discussion, what are the thoughts about using a MT 3 bladed prop. I think I remember the weight is 55lbs so it is more inline with the Hartzell. That should help with cg issues. Besides the 12,500 price any other issues?

My fault for getting the thread off topic, but since you asked....Vans did a bunch of comparative performance testing on various props over a decade ago and published results in the RVator. As I recall Hartzell blended airfoil and Whirlwind provided the best cruise performance and the MT was several knots slower. After that report very few people put MT props on their RVs....Way more cost for less performance doesn't sell too well. That said, it's possible MT has since developed a newer blade design better suited for the RV series, you'd have to research to find out. Also FWIW three blade props from any manufacturer tend to have reduced cruise performance compared to two blades (hence the old saying "two for the go, three for the show"). Three blades also make removal of the lower cowl more difficult and shipping the prop for repair or overhaul a lot more difficult & expensive. So...thats why you see so few 3-blade props on RVs.

RV6_flyer 07-30-2017 11:23 AM

Quote:

Originally Posted by redbaron (Post 1191449)
Take a serious look At the new Viking engines they have been upgraded and include some with turbo charging.

Not sure why anyone would not follow Van's Aircraft recommendation on engines for an aircraft as expensive as the RV-14(A) kit. They designed the aircraft around two engines. An overweight under powered Honda engine conversion is something that I would not walk away from, I would RUN as fast as I could to get away from it.

David Paule 07-30-2017 11:40 AM

Quote:

Originally Posted by czechsix (Post 1191403)
....Hartzell... ...transmits lots of vibration back into the airframe (typical of any metal prop)....

A good dynamic balance will fix that.

Dave

czechsix 07-30-2017 12:33 PM

Quote:

Originally Posted by David Paule (Post 1191514)
A good dynamic balance will fix that.

The Hartzell on my -8A was dynamically balanced, but the metal blades don't absorb the engine power pulses, so they get transmitted back into the airframe. Not as noticeable at higher RPMs as it is at lower RPMs and especially during shutdown. The first time I got in a friend's -7A with a Whirlwind prop, it felt more like a car when he started the engine. Much smoother...those carbon fiber blades absorb a lot more of the power pulses than metal.

If you were flying a turboprop, metal vs composite blades wouldn't make any difference as long as the prop is balanced, but not so on piston engines.

MED 07-30-2017 05:49 PM

I spoke with several people at Oshkosh about the differences between the Hartzel aluminum prop and the composite. A couple of discussions helped me to decide to spend the extra $ and buy the composite. Specifically, composite props are "smoother" with less vibration transmitted to the airframe and engine environment, leading to fewer engine baffle cracks, etc. The second advantage, according to Hartzel, is that the composite prop leading edge is nickel, which is much harder than aluminum, leading to a reduced chance of prop nicks. Plus, they said if a nick occurred, leading to a crack in the leading edge, it was a simple job to replace the leading edge. Hartzel said by replacing the leading edge at overhaul, you would essentially have new blades. Unfortunately, the difference in cost is non-trivial. :eek:

rwtalbot 07-30-2017 05:54 PM

Quote:

Originally Posted by MED (Post 1191592)
The second advantage, according to Hartzel, is that the composite prop leading edge is nickel, which is much harder than aluminum, leading to a reduced chance of prop nicks.

When you hit something soft it takes a dent. If you hit a harder material it cracks. That has been the experience on MT blades for years. Perhaps the Harzell doesn't suffer as much. If it were me I would call my local prop shop and ask their advice.

Bigortho 08-13-2017 05:46 PM

RV-14A with Superior XP-400
 
We're building our RV-14A at Synergy in Eugene, OR. This is a followup to my post in Jan 2017. Ultimately we purchased and built our XP-400 at the Superior's build facility in Dallas, TX in Feb 2017. My son and I assembled it in 2 ? days and it started right up in the test cell. We build our experimental planes for "educational & recreational" purposes - why shouldn't the same philosophy apply to our engines! After all, how better to understand, maintain & diagnose our engine than to have put it together ourselves.

This week we finally mounted it to our plane. The Superior A&P's said it was no more difficult than mounting the IO-390. Other than torquing the Dynafocal #1 Bolt adjacent to the #4 Cylinder Pushrod Tube, we had no difficulties. *We used a shaved down box wrench to slip into the narrow space between the pushrod tube and crank case. *I have subsequently learned that Lycoming has a special (expensive) tool just to tighten this nut.

We then fit the Hartzell Prop Governor and B & C Alternators (both 60 Amp Boss Mount belt driven primary & 40 amp B/U to the vacuum pump pad) with Vans supplied hardware without difficulty. *The fuel injector line to the #3 cylinder had to be bent slightly to accommodate the Prop Governor cable bracket (which the Lycoming 390 also requires be done).

The Vans Firewall Forward Kit supplied baffling fit the XP-400 with minimal trimming - which the Lycoming 390 also requires. *So, all-in-all, I?d say that installing the XP-400 is no more difficult than installing a Lycoming 390.

So, in my opinion, the advantages of the XP-400 over the Lycoming 390 are:

15 extra HP
Better Oil Path Flow with injectors to cool & lubricate the cylinders
P-Mag instead of Slick Magneto Ignition
Cold Air Induction
Choked Nitrided Cylinders to maintain compression
Horizontal,*Aluminum Sump that provides the extra space under the cowling to install Vetterman Exhaust with sound mufflers
The opportunity to build the engine at the Dallas facility.
Cheaper Price

The day after we uncrated our engine, a fellow RV-14A builder at Synergy used our crate to pack up his installed IO-390 and ship it back to Lycoming to have the Connecting Rod wrist pin bushings replaced as required by the new mandatory AD. As Synergy uses a different source for connecting rods & bushings - their engines are not subject to the recall.

A quote from my Superior build technician, Darrell Ingle, "we get our SL13923A bushings from a different vendor source than Lycoming so your connecting rods and bushings are good and don't fall under that Service Bulletin."

Tomcat RV4 08-13-2017 07:17 PM

I thought we are experimenters, made adaptors to mount 2.5 Subaru STOCK 165HP, wrx engine,to same o-320 engine mount, SDS Computer,to run ignition ,fuel injection, because RV 4, had to build modified cowl,any side by RV would be piece of cake ! Stock headers with,resonators from center pipe, made quieter than 172,,same awesome performance as
any RV 4,yet on car gas/achohol. A real hoot ! Also used stock suby fuel pumps in each tank! Had to plumb return lines for FI...Tom


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