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RV-14 Engine choice

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?
 
Viking aircraft engines

Take a serious look At the new Viking engines they have been upgraded and include some with turbo charging.
 
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.
 
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.
 
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.
 
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:
 
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.
 
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."
 
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
 
Thanks for the update on your XP-400. I hear the stock exhaust is a difficult fit on the XP. Did you go w/ a Vetterman Exhaust?
 
re RV-14A with Superior XP-400

Bigortho-

I'm curious about your message. You reported that a fellow builder at Synergy shipped his Lycoming 390 back to Lycoming for the connecting rod wrist pin bushing replacement AD. The published list of affected engines included in that AD does not include any IO-390's.http://www.lycoming.com/sites/default/files/SB632B%20Connecting%20Rod%20Identification.pdf

Did that builder have an IO-390 or some other engine? Does anyone know if any IO-390's are impacted by SB632? Is the list in the service bulletin incomplete?
 
I spoke with a builder at Synergy about his experience installing a Titan 370 in his 14. He alluded to numerous headaches with the cowl, exhaust, intake, CofG. The XP-400 sounds less troublesome. Although so far there's only a sample size of one!

How does the weight of the XP-400 compare to the Lycoming? Did you have to take measures to address CofG?
 
Lycoming AD

Bigortho-

I'm curious about your message. You reported that a fellow builder at Synergy shipped his Lycoming 390 back to Lycoming for the connecting rod wrist pin bushing replacement AD. The published list of affected engines included in that AD does not include any IO-390's.

Did that builder have an IO-390 or some other engine? Does anyone know if any IO-390's are impacted by SB632? Is the list in the service bulletin incomplete?

I was mistaken. It was a 320 that was shipped back. But the 390 is just a bored out 360, so probably uses the same defective connecting rod. The 390's haven't been flying long enough to throw any rods yet. Thus Lycoming hasn't extended the AD to the 390. Until Lycoming definitively declares the 390 safe from the recall, I would be concerned.
 
XP-400 Weight

I spoke with a builder at Synergy about his experience installing a Titan 370 in his 14. He alluded to numerous headaches with the cowl, exhaust, intake, CofG. The XP-400 sounds less troublesome. Although so far there's only a sample size of one!

How does the weight of the XP-400 compare to the Lycoming? Did you have to take measures to address CofG?

The XP-400 weighs only 2 lbs more than the 390. My Whirlwind 74 RV prop weight is more than 10 lbs lighter than the Hartzell. I added a 40 amp B&C backup alternator to the vacuum pump pad. I may yet exchange the Oddessy Battery for an EarthX lithium that saves 10 lbs. it will all be balanced out in the end
 
IO-390

Bigortho-

I'm curious about your message. You reported that a fellow builder at Synergy shipped his Lycoming 390 back to Lycoming for the connecting rod wrist pin bushing replacement AD. The published list of affected engines included in that AD does not include any IO-390's.http://www.lycoming.com/sites/default/files/SB632B%20Connecting%20Rod%20Identification.pdf

Did that builder have an IO-390 or some other engine? Does anyone know if any IO-390's are impacted by SB632? Is the list in the service bulletin incomplete?

I spoke with Lycoming Technical help a few days ago. The 390 is not impacted. The reference to the IO-390 gasket kit in the SB was a mistake. The IO-390 is never referenced by serial number or date of manufacture.
 
I was mistaken. It was a 320 that was shipped back. But the 390 is just a bored out 360, so probably uses the same defective connecting rod. The 390's haven't been flying long enough to throw any rods yet. Thus Lycoming hasn't extended the AD to the 390. Until Lycoming definitively declares the 390 safe from the recall, I would be concerned.

I think the connecting rod part # for the IO-360 and IO-390 angled valve engines is different from those effected by the AD that is why no angled valve engines are on the list.........
 
Bigortho, do you think the cowl will fit the xp-400 as is? My recollection is the Xp engine is 2 inches longer. Thanks for the info, now how bout to pictures too!
 
The XP-400 weighs only 2 lbs more than the 390. My Whirlwind 74 RV prop weight is more than 10 lbs lighter than the Hartzell. I added a 40 amp B&C backup alternator to the vacuum pump pad. I may yet exchange the Oddessy Battery for an EarthX lithium that saves 10 lbs. it will all be balanced out in the end

I've got 115 hours on RV-14A with XP-400/RV74 Whirlwind/EFII ignition and fuel injection/ duel EarthX lithium batteries. First engine is a shoe in for the IO-390 . Engine baffling fit perfectly (slight trim in the corners per the plans)
You do have to go to a modified exhaust as the standard exhaust runs into the bottom of the oil pan, I went with duel Vetterman headers and pipes,
installation was a snap.
I did my rear CG tests. I'm light up front with the prop and no mags but Aircraft preformed within the envelope as advertised.
there is a bit of re-routing for heat but that was pretty easy as well.
cliff
 
Do we have a price comparison between the XP-400 and the IO-390 ?


Like for like including all the twiddly bits !
 
Regarding the quadrant, I've had a few people contact me to thank me for the info on the quadrant and cable lengths. They've duplicated my install and are very happy with it. So don't let that stop you. It's pretty easy to install. I have no clue why Van's keeps their head in the sand on that one. They could easily make it an option.
 
XP400 Fuels

I fought this battle a couple years ago when I was going to decide. The efii system installed by Barrett's during the build was a big factor. I.e. Flying a system that had been tested on a test stand first. Robert of efii Protek says , below 9:1 you can run auto fuel and the efii system will accommodate the lower octane fuels to a point. The STC for auto fuel has a hard stop at 8000 feet due to the vapor pressure of fuel . That was never a factor for me as I live in Boulder Colorado so I wasn't burning auto fuel. Leaving efii out of the formula, which is where I started ., parts and maintenance on 400 was less costly at the time of my decision. And a smaller point, in the 400 you can pull a tappet without splitting the case to examine a cam load. It's a small item but when your trying to decide you look at all the factors. I also had a set of superior cylinders on an IO520 for 20 years and 2000 hours before an AD knocked them out. Cylinders were fine. Both engines are great. But there are a few differences such as cost and better internal cooling that helped tipped the scales even without EFII. (Robert corect me if I'm wrong on auto fuels). Very difficult choice but u won't go wrong either way
 
auto fuel

No problem with EFII/390 and premium auto fuel with up to 9:1 compression.
Higher compression engines should stick with 100LL.

As Cliff mentions, auto fuel shouldn't be flown over 8,000ft or in hot weather due to its higher vapor pressure.

Robert
 
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XP400 Fuels

I fought this battle a couple years ago when I was going to decide. The efii system installed by Barrett's during the build was a big factor. I.e. Flying a system that had been tested on a test stand first. Robert of efii Protek says , below 9:1 you can run auto fuel and the efii system will accommodate the lower octane fuels to a point. The STC for auto fuel has a hard stop at 8000 feet due to the vapor pressure of fuel . That was never a factor for me as I live in Boulder Colorado so I wasn't burning auto fuel. Leaving efii out of the formula, which is where I started ., parts and maintenance on 400 was less costly at the time of my decision. And a smaller point, in the 400 you can pull a tappet without splitting the case to examine a cam load. It's a small item but when your trying to decide you look at all the factors. I also had a set of superior cylinders on an IO520 for 20 years and 2000 hours before an AD knocked them out. Cylinders were fine. Both engines are great. But there are a few differences such as cost and better internal cooling that helped tipped the scales even without EFII. (Robert corect me if I'm wrong on auto fuels). Very difficult choice but u won't go wrong either way
 
XP400 Fuels

I fought this battle a couple years ago when I was going to decide. The efii system installed by Barrett's during the build was a big factor. I.e. Flying a system that had been tested on a test stand first. Robert of efii Protek says , below 9:1 you can run auto fuel and the efii system will accommodate the lower octane fuels to a point. The STC for auto fuel has a hard stop at 8000 feet due to the vapor pressure of fuel . That was never a factor for me as I live in Boulder Colorado so I wasn't burning auto fuel. Leaving efii out of the formula, which is where I started ., parts and maintenance on 400 was less costly at the time of my decision. And a smaller point, in the 400 you can pull a tappet without splitting the case to examine a cam load. It's a small item but when your trying to decide you look at all the factors. I also had a set of superior cylinders on an IO520 for 20 years and 2000 hours before an AD knocked them out. Cylinders were fine. Both engines are great. But there are a few differences such as cost and better internal cooling that helped tipped the scales even without EFII. (Robert corect me if I'm wrong on auto fuels). Very difficult choice but u won't go wrong either way
 
XP-400 & RV-14A Cowl

RV-14A with Superior XP-400 Installation Tips

Exhaust System

The Vans Lycoming IO-390 Exhaust System does not fit the Superior XP-400: you must buy a $1395 Vetterman Exhaust (currently a dual independent exhaust system with no crossover pipes) to fit the XP-400. The dual pipes do not enter the tunnel, but exit the cowl bottom anterior to the nose wheel hinge, so the cowl needs two cutouts adjacent to the nose wheel cutout - not a big deal.

The Vetterman Exhaust uses 2? pipes, which results in much lower back pressure than the Vans Single Exhaust pipe. Both Heat Exchange & Sound Mufflers can be added to the Vetterman Exhaust as the low profile Superior XP-400 Horizontal Cold Air Injection Manifold allows room under the lower cowl for muff/mufflers.

When you delete the Vans Exhaust from the Firewall Forward Kit, you also delete the cabin heat components: You must order 2" SCAT Tube, 10 hose clamps and the T- Splitter [VENT-00002] from Vans. A SCAT runs from the Fresh Air intake [CB-0007] located in the right cowl vent to a splitter, which shunts air to the right & left muffs. Another pair of SCATs connects the muffs to the Cabin Heat Valves.

If you want truly independent heat controls for both the pilot & copilot you must also order two FF-00084 Cabin Heat Valve Covers. Otherwise if one side is open and the other closed, most of the heat will shunt out the bottom of the closed valve.
 
RV-14A with Superior XP-400 Installation Tips

Exhaust System

The Vans Lycoming IO-390 Exhaust System does not fit the Superior XP-400: you must buy a $1395 Vetterman Exhaust (currently a dual independent exhaust system with no crossover pipes) to fit the XP-400. The dual pipes do not enter the tunnel, but exit the cowl bottom anterior to the nose wheel hinge, so the cowl needs two cutouts adjacent to the nose wheel cutout - not a big deal.

The Vetterman Exhaust uses 2? pipes, which results in much lower back pressure than the Vans Single Exhaust pipe. Both Heat Exchange & Sound Mufflers can be added to the Vetterman Exhaust as the low profile Superior XP-400 Horizontal Cold Air Injection Manifold allows room under the lower cowl for muff/mufflers.

When you delete the Vans Exhaust from the Firewall Forward Kit, you also delete the cabin heat components: You must order 2" SCAT Tube, 10 hose clamps and the T- Splitter [VENT-00002] from Vans. A SCAT runs from the Fresh Air intake [CB-0007] located in the right cowl vent to a splitter, which shunts air to the right & left muffs. Another pair of SCATs connects the muffs to the Cabin Heat Valves.

If you want truly independent heat controls for both the pilot & copilot you must also order two FF-00084 Cabin Heat Valve Covers. Otherwise if one side is open and the other closed, most of the heat will shunt out the bottom of the closed valve.

If an RV-14 heat system is installed per plans there is a slight interaction between operation of the left and right heat controls but it is minor.
As designed the cabin heat system works very well because of the dual/series'ed heat muffs and the use of one FF-00084 cover. You should never install an FF-00084 cover on both heat valves on an RV-14 (or any other model).
The whole purpose of the heat valves being designed the way they are (constant flow, so that even if the heat is shut off, the valve allows air to flow through the system) is to prevent system over heating. There must be constant flow through the system to prevent over heating of the exhaust system in the areas covered by the muffs, and the muffs and hose themselves.

Regarding the potential performance differences in the two exhaust systems....?
I am still waiting for someone to provide some test data showing a performance difference between the two.
Detailed flight testing was done on the current system using a number of different collector pipe configurations. The simplest design was used since testing showed no easily measurable difference between them.

It is not data obtained with controlled testing, but at least one RV-14 which is reported to have a tweaked engine (higher than standard HP) and a Vetterman exhaust system has speeds and fuel flows that are no different from the company prototypes.
 
Vetterman Dual Exhaust

You're right about the necessity of air constantly flowing through the mufflers and dual covers should not be used. The Vans heat muffs are arranged in series on the right side of the engine and a T-Splitter is used to direct warmed air to both cabin heat valves.

As the Vettermans has two independent exhaust systems, you need to split the air before it flows to the right and left muffs. This entails running a long SCAT from the right intake to a splitter at the back of the engine as there's no room up front for a crossing SCAT Tube.

An alternative is to place a second fresh air flanged duct on the rear left baffle for the left muff. Now each heat system is independent and no covers should be used on with cabin heat valve. This is what I plan to do and have ordered the parts from Spruce.
 
RV-14 Engine options and exhaust system

The engine I have is the Superior XP-400, but was assembled by Aero Sport Power who designates the engine as a IO-400-M1S. This engine is a very close "clone" of the Lyc 390, and in my experience, any accessory that is designed for the 390 can be bolted onto the Superior 400, including the baffle kit and exhaust system provided by Van's. I would say the engine is very similar to the Lyc Thunderbolt 390 option-- I had my engine ported and flow matched and ignitions are dual Light Speed Engineering PIII. The prop is the Hartzell BA 74, and this engine and prop are a great combination.
 
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One cost that is often overlooked is resale value. Consider what a optional engine choice may have on re sale down the road.
 
IMHO, the resale value would be much higher than a piston engine IF
the turbine engine lives up to the proposed specs.

-TB
 
How about the following turbine( IF it becomes available ) for an RV-14?

https://turb.aero/ Note the fuel consumption.

Target price is $65K.

TBoone ( 0TX1 )

Pros: FADEC Jet A burning engine
Similar performance specs to IO-390

Cons: 2x the cost
50% more fuel burn at cruise
Custom cowl, firewall forward package: cooling, cabin heat, fresh air for combustion plenum all need design

Custom engine mount as current mount incorporates nose wheel

This will truly be experimental aviation
 
Sorry risking a rehash of old debates...

Looking hard at either a RV-7A or RV-14a, and leaning trades the 14A for added room and stability. I’m not so much a fan of the IO-390-EXP’s added upfront acquisition costs or maintenance costs down the road (cylinders).

Questions:
* It is frowned upon using an IO-360 rather than the 390?
* Is there that much performance difference in the real world?
* If going IO-360, is it better to stick with the RV-7a?

The XP-400 seemed like a nice option, but life moves on.
 
Sorry risking a rehash of old debates...

Looking hard at either a RV-7A or RV-14a, and leaning trades the 14A for added room and stability. I’m not so much a fan of the IO-390-EXP’s added upfront acquisition costs or maintenance costs down the road (cylinders).

Questions:
* It is frowned upon using an IO-360 rather than the 390?
* Is there that much performance difference in the real world?
* If going IO-360, is it better to stick with the RV-7a?

The XP-400 seemed like a nice option, but life moves on.

————-

I originally installed XP-400 that I personally assembled at Superior. When it was recalled, Barrett Precision rebuilt it as an IO-390 using Lycoming jugs, pistons and crank.

I built my RV-14 at Synergy, where other RV-14 builders installed Titan 370’s.

I chose a 14 because I’m 6’ 6” and weigh 275, so I needed the room and useful load. Smaller folk are happy with the RV-9.
 
I’m guessing this turbine makes rated cruise power into the flight levels around Class A?

It takes a massive flat rated capacity for a turbine to make rated power into the flight levels and that wouldn't be too useful for a -14 anyway with the relatively low Vne unless you just wanted an awesome ROC up there.:)
 
Pros: FADEC Jet A burning engine
Similar performance specs to IO-390

Cons: 2x the cost
50% more fuel burn at cruise
Custom cowl, firewall forward package: cooling, cabin heat, fresh air for combustion plenum all need design

Custom engine mount as current mount incorporates nose wheel

This will truly be experimental aviation

Yes, but a guy would have the RV everyone wanted to see at the airport. :7)

50% more fuel burn, but the fuel is 25% less and no leaded fuel substitution issues.

Plus a gut could fly it to Nairobi Africa and get fuel for it all over the place. Now there’s a real plus! ;7)
 
Pros: FADEC Jet A burning engine
Similar performance specs to IO-390

Cons: 2x the cost
50% more fuel burn at cruise
Custom cowl, firewall forward package: cooling, cabin heat, fresh air for combustion plenum all need design

Custom engine mount as current mount incorporates nose wheel

This will truly be experimental aviation

Just curious, how much turbine time do you have?

-TBoone
 
Rear mounted governor LYC IO-360A1B6

Has anyone attempted to use the rear mounted governor LYC IO-360A1B6 200HP engine in the RV-14 taildragger?
The latest relevant posts seem to be of 2017 vintage and I’m wondering if there’s been any new info regarding the use of this engine and solving (hopefully) the issues surrounding using it in the RV-14.
 
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