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RV9 200HP Yamaha Sidewinder

One of the things I find exciting about Teal’s project is that we might finally get some long-term experience with these engines. The competition STOL guys have done great with them, but don’t fly as many hours as someone with a cruising RV - so we might actually get data on how long one of these lasts in real-world aviation applications!

Please keep us informed Teal….

Paul
 
My -9A has an IO-320 at 9:1 compression, dual lightspeed and AFP injection. I'm pretty consistent at 8,000-9,000 ft 147kts TAS, 6.7 gph, and 25* LOP. 64% power.
Ok, On this mornings flight I tried to duplicate some of the other RV9 cruise flight numbers.
At 8k ft and 150KTAS it was indicating 8.9GPH. at best RPM and manifold pressure which was 6300 RPM and 35.7INHg.
At 10k ft and 150KTAS it was indicating 8.5 GPH and 6300 , 35.3INHg.
Important to note that at these cruise numbers the AFR is still only 12.9-13. so there is much leaning to go in the tune at these manifold pressures. Also we are still tweaking on the fuel flow computer calcs each flight.
Perhaps of some importance is the above numbers represents about 20MPG (no winds). At the end of the last few flights I have drained the fuel and looked at total miles covered and it averages about 21MPG. That seems pretty good considering on the 1 hour flight I climbed to at least 12kft. Yes, I get some back on the glide descent but not equal.
In the end though my goal wasnt to try to get better fuel economy than the standard aircraft engine I think they do a great job of already.
 
Important to note that at these cruise numbers the AFR is still only 12.9-13. so there is much leaning to go in the tune at these manifold pressures.

Teal, do you have a form of inflight manual mixture control? How about individual EGT?
 
Ok, On this mornings flight I tried to duplicate some of the other RV9 cruise flight numbers.
At 8k ft and 150KTAS it was indicating 8.9GPH. at best RPM and manifold pressure which was 6300 RPM and 35.7INHg.
At 10k ft and 150KTAS it was indicating 8.5 GPH and 6300 , 35.3INHg.
Important to note that at these cruise numbers the AFR is still only 12.9-13. so there is much leaning to go in the tune at these manifold pressures. Also we are still tweaking on the fuel flow computer calcs each flight.
Perhaps of some importance is the above numbers represents about 20MPG (no winds). At the end of the last few flights I have drained the fuel and looked at total miles covered and it averages about 21MPG. That seems pretty good considering on the 1 hour flight I climbed to at least 12kft. Yes, I get some back on the glide descent but not equal.
In the end though my goal wasnt to try to get better fuel economy than the standard aircraft engine I think they do a great job of already.

Teal,

What is best prop RPM at those speeds/altitude?

Thank you,
 
Teal, do you have a form of inflight manual mixture control? How about individual EGT?
No, with the exception of switching between preset fuel maps that was built prior. I am told that I can connect a potentiometer to one of the ECU's analog inputs for a manual mixture control but I am not really interested in doing that at this point. currently I am switching between a few different tunes during flight then going back through the log with my tuner guy and making fine adjustments until we have an all around good tune. I can always switch over to a for example lean of peak tune in the future if thats what I want but I am ot sure how exactly this engine will behave lean of peak yet.
 
I was kind of liking the 2200-2300 Rpm for this last flight but I have not spent to much time in the 8-9kft. Most of my time so far has been 12-15kft.

Great looking install! With that much MP available, I would love to hear how it performs at 17,500. My O-360 -4 does pretty good up there, but starts to fall off above 15k. I would imagine the -9 wing gets more efficient up high.
 
Ok, On this mornings flight I tried to duplicate some of the other RV9 cruise flight numbers.
At 8k ft and 150KTAS it was indicating 8.9GPH. at best RPM and manifold pressure which was 6300 RPM and 35.7INHg.
At 10k ft and 150KTAS it was indicating 8.5 GPH and 6300 , 35.3INHg.
Important to note that at these cruise numbers the AFR is still only 12.9-13. so there is much leaning to go in the tune at these manifold pressures. Also we are still tweaking on the fuel flow computer calcs each flight.
Perhaps of some importance is the above numbers represents about 20MPG (no winds). At the end of the last few flights I have drained the fuel and looked at total miles covered and it averages about 21MPG. That seems pretty good considering on the 1 hour flight I climbed to at least 12kft. Yes, I get some back on the glide descent but not equal.
In the end though my goal wasnt to try to get better fuel economy than the standard aircraft engine I think they do a great job of already.

Those fuel flow numbers are not bad at all, considering. I would be very cautious about LOP operations on a turbo engine. If it was me flying that engine with the turbo performance up high on 91E10 or 93E10, I would be happy with the lower priced fuel and just run the factory tune - no sense burning a piston. I routinely see nm/gal readings of 21-23 in cruise flight, you're right in the neighborhood.
 
Great looking install! With that much MP available, I would love to hear how it performs at 17,500. My O-360 -4 does pretty good up there, but starts to fall off above 15k. I would imagine the -9 wing gets more efficient up high.
It climbs really, really good up high. But Cruise speeds are not as good as they should be. I feel that I am running out of propeller surface area, Not pitch because I can continue to increase pitch and still load the motor but increased HP is not equating to increased speed. Airmaster tells me this is the largest blades they can offer at this time. The highest that I have taken it was 15.5k and it will still climb around 1.5-2k ft per min. at 15k I think I was still able to make 44INhG manifold pressure. I am considering trying a fixed pitch propeller that performance up high. Sterna is telling me that they have a blade they want me to try. Anybody have experience with them?
 
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I would like to post pictures on my post. Can someone please tell me how to do that?

When you start your message there is a paperclip icon at the top next to a smiley face.
1. Click the icon.
2. Browse for and select the photo(s) you want to insert as the attachment(s).
3. Upload photo(s). (Repeat steps 2 and 3 for multiple photos.)
4. Close the window when you have finished uploading.
5. Click on the paperclip again to manage the attachments.
6. Choose the photo(s) you want to attach. They will be inserted into the body of your text with a . You can then add them to the end or insert them in between paragraphs, etc.
7. Hit submit reply to post.

If you want to add a link to a photo then you can use the Insert link icon (world with a link) under the smiley face. Be careful of Doug's rules when posting from a non-advertiser or outside web site. See his rules here so not to get into any trouble.
 
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I would like to post pictures on my post. Can someone please tell me how to do that?

Pictures must be in your computer file.
Click on this paper clip...
paperclip.JPG

Click on choose a file...
choose a file.JPG

Click on the picture file and click open.
Click upload. File will display....
file will show.JPG

Repeat for all pictures you want in the post.
Click on the post page location to clear the screen.
Type your message. Then place curser where you want
the picture. Click the paper clip again.
set pic.JPG

The files will show up. Pick the file you want in that spot.
place pic.JPG

The attached file will look like this.....
should look like this.JPG

Now, preview your post....
preview of the post.JPG
 
Ok, On this mornings flight I tried to duplicate some of the other RV9 cruise flight numbers.
At 8k ft and 150KTAS it was indicating 8.9GPH. at best RPM and manifold pressure which was 6300 RPM and 35.7INHg.
At 10k ft and 150KTAS it was indicating 8.5 GPH and 6300 , 35.3INHg.
Important to note that at these cruise numbers the AFR is still only 12.9-13. so there is much leaning to go in the tune at these manifold pressures. Also we are still tweaking on the fuel flow computer calcs each flight.
Perhaps of some importance is the above numbers represents about 20MPG (no winds). At the end of the last few flights I have drained the fuel and looked at total miles covered and it averages about 21MPG. That seems pretty good considering on the 1 hour flight I climbed to at least 12kft. Yes, I get some back on the glide descent but not equal.
In the end though my goal wasnt to try to get better fuel economy than the standard aircraft engine I think they do a great job of already.

With the big bore Lyc's, we are getting good fuel economy by running lean. These engines are turning low RPMs, so easy to get very lean. In the 10, I am cruising mostly at 50-75* LOP, which is probably about 17:1 or a bit less. Given you are turning higher RPMs and possibly can't get as lean, there may be better economy by running 15:1 with the higher speed. Not sure how lean you can get with 35" of MAP though. On my porsche boxer engine with turbo, I go quite lean in the tables with the closed loop mode, but it is in cruising condition at lower RPMs with no real boost involved. Never tried getting less than 12.5:1 on the 8 PSI of boost. Too scarry and not worth it for me as, unlike the plane in cruise, I don't spend great deals of time there. I would be quite cautious about anything below 13:1 when boosted. That said, I have no real experience to offer. Do you have an electronically controllable waste gate? Maybe an idea is to drop the boost way down and try lean settings at cruise. Lower RPMs with a coarser pitch may be a benefit given the limited blade area you referenced.

One thing I do know is that each combustion chamber design has different characteristics that limit AFR and advance, so be sure your tuner has experience with this engine if he is recommending AFRs lower than 13:1 on 35" of MAP. leaner AFR's can get things pretty hot at high MAPs. When speaking of pistons and rings, heat kills. Then again, many engines designed for high boost applications have pretty low dynamic compression ratios and therefore aren't producing a lot of heat at low boost levels and therefore don't need excess fuel there. Devil is in the details.

Larry
 
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I'd generally agree with Larry here on leaning too far with this high specific output engine. Unless it has oil jetted, forged pistons, the heat flux into the piston crowns and upper ring land areas may make for short life when running near stoich.

Most automotive engines (also relatively high specific output) typically run in the 11 to 1 range at high power settings to keep the pistons alive.

A Lyc at 75% only has a specific output of 23hp/L. This engine would be at 135hp/L to match an O-360- almost 6 times the specific output.
 
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Larry and Ross, Thank you for the advice.
The engine does have oil squirters cooling the pistons but I am not sure if they are forged.
The only comparative engine that I have data on is the fuel injected Rotax 912. I communicate often with Thomas Hauklien the owner of edge performance. They make an after market EFI and turbo system for these engines. He claims they run 1500-1550F on EGT's at cruise power settings and AFR of 14.5-14.9.
Currently I am at 1430-1450 at cruise power settings. I definitely will be proceeding with caution
 
Good stuff. Kudos for putting the "E" back in Experimental. A most interesting project.:)

We're all hoping it lasts well and could pave the way for a few more wishing for something different up front.
 
Teal,
I looked at this at Oshkosh and it's very impressive. I'm interested in knowing the outcome of the prop issue you experienced with the airmaster. Have you considered a four blade prop to gain the extra surface area you where referring to in previous post? How are you controlling boost. I have so many questions but I will leave them for another time. Thanks for your work paving the path less followed.
 
A local builder put a similar, non-turbo'd Yahama on his CH701 using a belted reduction drive. Throttle response was almost silly-fast and the power output was impressive. Visually these engines appear to be of very high quality. These are amazing engines and, if we can get the bugs worked out, likely represent one of the brightest spots in "non-aviation" engine conversions.
 
Forged pistons and oil squirters. That's what you need to make it reliable at these specific outputs.

Whoever wrote the article didn't research production turbo engines with ITBs very well.

Lotus blew through twin Dellorto sidedraft carbs on their 2.2 turbo way back in 1989.

Nissan produced ITB turbo versions of the SR20 and RB26 over 20 years ago if I recall correctly.

I could be missing some others but Yamaha is hardly the first and despite the hype in this article, there is no new technology here. Nothing really different from state of the art automotive turbo engines from 25 years ago.
 
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Good job!!

Teal,

Great to hear about this. I can personally appreciate how much work it is putting an alternative engine in an RV....and how much fun it is.

It is good to hear people offer support and encouragement and I hope people continue to respect it is your choice and keep the parental cautionary verbage to a nano-minimum.

I know here in KY, Justin Richardson, who just put a Sterna prop on his RV. I can't remember which model of RV he has. Ill encourage him to jump on here and comment about the prop.
 
It is good to hear people offer support and encouragement and I hope people continue to respect it is your choice and keep the parental cautionary verbage to a nano-minimum.

There's lots of newbies who are in over their heads, so providing unbounded enthusiasm can show up more accidents and in higher insurance rates for all of us, maybe in more closed airport.

"It's a homebuilt and you can do what you want... but the laws of physics don't care what you want."

Ed
 
Prop Diameter?

It climbs really, really good up high. But Cruise speeds are not as good as they should be. I feel that I am running out of propeller surface area, Not pitch because I can continue to increase pitch and still load the motor but increased HP is not equating to increased speed. Airmaster tells me this is the largest blades they can offer at this time. The highest that I have taken it was 15.5k and it will still climb around 1.5-2k ft per min. at 15k I think I was still able to make 44INhG manifold pressure. I am considering trying a fixed pitch propeller that performance up high. Sterna is telling me that they have a blade they want me to try. Anybody have experience with them?

What diameter prop are you running? When 2.85 PSRU was introduced for Mazda rotary engines, that required a longer prop to absorb the extra hp produced; and many guys ended up increasing their prop length to ~76 inches.

Doug
 
Just a follow up to my cruise speed numbers. Currently I have been leaning out just a little bit and experimenting on longer trips with altitudes and cruise speeds. My last trip I was at 164KTAS at 12kft burning 8.1 and AFR of 13.5. All EGT's were around 1380f.Manifold pressure was 36INhG, throttle position 36%. At 9gph and 40INhG manifold it was at 168KTAS. At 14000 ft it was about 3kts faster for same fuel burn. but normally I like to not have to use oxygen so I stay around 12kft.
 
Nice job. Finally an alternative engine that can provide the performance of a lycoming. If you have a low pass video, i know everyone would love to see and hear it. I bet it sounds great. With the price of lycomings these days, i just can’t justify building anymore new planes.
 
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Just a follow up to my cruise speed numbers. Currently I have been leaning out just a little bit and experimenting on longer trips with altitudes and cruise speeds. My last trip I was at 164KTAS at 12kft burning 8.1 and AFR of 13.5. All EGT's were around 1380f.Manifold pressure was 36INhG, throttle position 36%. At 9gph and 40INhG manifold it was at 168KTAS. At 14000 ft it was about 3kts faster for same fuel burn. but normally I like to not have to use oxygen so I stay around 12kft.

Teal,
You may have found a bit of a sweet spot at 164 KTAS in cruise. You added 0.9 GPH and only got 4 more knots (2.4% more speed for 11.1% more fuel).

I fly my RV-6A (O-360) at 155 KTAS (11,500 ft MSL) burning a bit less than 8 GPH at approximately peak EGT (it's carbed). You're already doing better than I on a MPG basis.
 
Teal,
Very interesting project. I wish you much success.

Are you using the OEM ECU hardware (and reprograming it) or a 3rd party ECU ?

What boost control scheme are you using ? Is the waste gate mechanically controlled, or controlled by the ECU?

Are you using the OEM knock sensor and adjusting timing in the ECU ?

How about the O2 sensor — using closed loop AFR control?

Peter
 
Are you using the OEM ECU hardware (and reprograming it) or a 3rd party ECU ?
No, It is LINK brand ECU sold and tuned by Hypersports. first 20 hours of flight time was adjusting ECU tune.[/COLOR]

What boost control scheme are you using ? Is the waste gate mechanically controlled, or controlled by the ECU?
The waste gate is controlled by ECU and conservatively set by tune to not build to much boost at the lower rpms. Also utilizes knock sensor overlay table in tune to open waste gate or drop manifold pressure if knock is sensed.

Are you using the OEM knock sensor and adjusting timing in the ECU ?
Yes, ECU is adjusting timing, fuel, manifold pressure all the time based on many variables including knock.

How about the O2 sensor — using closed loop AFR control?
Yes running an O2 sensor in closed loop but can switch to open loop at anytime and use generic fueling tables in the case the O2 sensor fouls.

Peter[/QUOTE]
 
G100UL

Once G100UL is widely available, maybe we will see more of these conversions. Could be the start of an exciting time in EAB.
 
FWF Kit

This question may have been previously asked, but are you considering making a FWF kit?….(all or part)?
 
Type in you tube:
SkyTrax yamaha sidewinder RV9 in you tube for a couple fly byes and short field takeoff
 
Excellent, thanks. Nice use of modern technology. Tune carefully!
With time and expertise you could arrive at a very robust package with excellent performance and ease of use.

Are you using the OEM ECU hardware (and reprograming it) or a 3rd party ECU ?
No, It is LINK brand ECU sold and tuned by Hypersports. first 20 hours of flight time was adjusting ECU tune.[/COLOR]

What boost control scheme are you using ? Is the waste gate mechanically controlled, or controlled by the ECU?
The waste gate is controlled by ECU and conservatively set by tune to not build to much boost at the lower rpms. Also utilizes knock sensor overlay table in tune to open waste gate or drop manifold pressure if knock is sensed.

Are you using the OEM knock sensor and adjusting timing in the ECU ?
Yes, ECU is adjusting timing, fuel, manifold pressure all the time based on many variables including knock.

How about the O2 sensor — using closed loop AFR control?
Yes running an O2 sensor in closed loop but can switch to open loop at anytime and use generic fueling tables in the case the O2 sensor fouls.

Peter
[/QUOTE]
 
No firewall kit plans at this time.

Man, if you did, I think there’d be a really big market for it. We desperately need an alternative to the Lycoming. With the never ending Lycoming price increases, it’s really pushing a lot of people out of this sport. You are showing some really impressive numbers with your airplane and I think a lot of people would love to have an option like this for their build.
 
Today I tested some more high altitude efficiencies. We added a boost target overlay table to the tune so that I could manually increase or decrease the current boost target. I did this so that I could increase throttle position and open waste gate to make up for it. I found some efficiencies here. My ECO cruise before adjusting boost target was: 29% TPS 34" manifold. After increasing throttle and reducing boost target while maintaining 6GPH it was: 44% TPS and 28" manifold. This increased RPM by 200 and yielded about 3 MPH increase. I was at 15kft indicating 134MPH and 31f outside. So a true airspeed of 179MPHT or 155KTS. On 6 GPH this seems pretty amazing to me. in these setting the AFR is about 13.7:1. EGTS are all about 1290f in these settings. Calculated HP was 87hp.
 
Today I tested some more high altitude efficiencies. We added a boost target overlay table to the tune so that I could manually increase or decrease the current boost target. I did this so that I could increase throttle position and open waste gate to make up for it. I found some efficiencies here. My ECO cruise before adjusting boost target was: 29% TPS 34" manifold. After increasing throttle and reducing boost target while maintaining 6GPH it was: 44% TPS and 28" manifold. This increased RPM by 200 and yielded about 3 MPH increase. I was at 15kft indicating 134MPH and 31f outside. So a true airspeed of 179MPHT or 155KTS. On 6 GPH this seems pretty amazing to me. in these setting the AFR is about 13.7:1. EGTS are all about 1290f in these settings. Calculated HP was 87hp.

Using your numbers, that's a BSFC of .41, not bad.

Is there some reason you can't run WOT and decrease boost? Should be more efficient still.

EGTs are surprisingly cool.
 
Sure, if I replaced the current actuator assembly with a weaker spring model. The ECU is commanding 0 duty cycle from the boost solenoid at these settings. I am not sure that there is to much more efficiency to be had by replacing the actuator to make it worth it. The Manifold air temps (after intercooler) was 50f. which seems like this would help with the cool EGT's
 
Sure, if I replaced the current actuator assembly with a weaker spring model. The ECU is commanding 0 duty cycle from the boost solenoid at these settings. I am not sure that there is to much more efficiency to be had by replacing the actuator to make it worth it.

I assume you're using a a single port/ single chamber wastegate actuator and the ECU is running a solenoid valve teed into the control line leaking off pressure to the actuator chamber?

The throttle is still more than half closed which would result in somewhat higher pumping losses which the compressor has to make up. I'm a bit surprised you haven't had surge issues up high but I suppose the stock compressor is pretty small and even at half throttle, it's still right of the surge line.

Anyway, theory aside, it seems to be working well and is a way cool installation. This is what true Experimental aviation is all about in my view. Love what you've done here! :cool:
 
That waste gate control arrangement is exactly what I have.
This turbo is really small but I can still make over 40" manifold at 18kft.
One thing that you might be considering in your pumping loss assumption is the size of these individual butterfly valves. These butterfly valves (3 of them) have a huge opening even at 50% throttle so they are not causing much restriction.
It has amazed me every time I take it up high. If I could just get a larger prop to absorb the power up high it would really be good.
thanks.
 
I forgot it has ITBs. You're right, probably minimal restriction at half throttle.

Turbos are wonderful and you need a lot of prop up high to absorb the power. I have the same issue above about 10,000 feet with mine. 76 inch 3 blade even at full coarse, I can't hold the RPM where I want to above 32 inches.
 
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That waste gate control arrangement is exactly what I have.
This turbo is really small but I can still make over 40" manifold at 18kft.
One thing that you might be considering in your pumping loss assumption is the size of these individual butterfly valves. These butterfly valves (3 of them) have a huge opening even at 50% throttle so they are not causing much restriction.
It has amazed me every time I take it up high. If I could just get a larger prop to absorb the power up high it would really be good.
thanks.

It's only money....... https://www.cattoprops.com/
 
FP props aren't the ticket for turbocharged engines as many people have discovered since you have a wider range of rpms and MAP available and power is maintained to higher altitudes where the air density is much lower for the prop.
 
I am currently talking with CATTO about a solution. I do like my constant speed prop currently but Feel there is efficiency that I am leaving on the table up high. We will see if a fixed pitch will be worth the trade off.
 
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