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Honda 1.8L on RV6A Now Flying!

Now that - I hope - all the electrical gremlins are happy, I am in the home stretch for tasks. I am doing some fit and trim work on the radiator scoop and installing the emp fairing. Once that is done I will install a mount for my stratux and IPAD and I should be ready to fly.

I have been flying with a local LODA instructor in his RV6A and things are progressing well.

I hope to fly in a few weeks.
 
panel pic

Here is a pic of my panel. I installed the IPAD today. I have it on a double jointed RAM mount which is why it sits a bit forward of the panel. I like the mount a lot. I was in the hangar so there is no GPS data on the screen etc.

I foreflight on the IPAD that is getting data from a stratux attached to a bracket that in the baggage area up next to the window on the passenger side.
 

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IPAD, Brakes, and spinner

We have the spinner drilled and almost done. The emp fairing done.

I stripped a brake bleeder on a matco brake. That made my day. A call to Matco and I had new one on the way.

After tearing apart the old one, I can see why it happened. Besides my meathead error, I was very suprised how very little threads are actuall on that bleeder. May be 4 turns of very fine thread. I went to NAPA to see if they had a bleeder that would fit, but they didn't. I have to say that the automotive ones that I saw were much more threads, probably on average about 10 threads on them. I know most who actually bleed brakes have probably loosened the bleeder in and out many times and never had an issue.

I have a new respect for the need (requirement) to be soft handed on that particular bleeder.

I have been doing my taxi work without the spinner. When I finally installed it I learned my bolts were less than 1/8 inch too short. I called Sam at Saber and he out to me immediately that day.

I got good service from Matco and Saber but honestly this week was a bit of a set back.

The good news is that I completed by flight training with my LODA instructor and he signed me off. I really benefitted from time with LODA CFI - Scott Cutler - out of Olympia Washington. Scott was great. Just what I needed to polish off my skills, after a few flights with Mike Seager in Vernonia. So I am good to go. I highly recommend Scott if you need an LODA instructor for time/endorsement in an RV6A.

Now I just need to get those prop bolts, Brakes bled, and finish the seats to get some air between be and the ground.

Depending on other "opportunities" and weather. I hope that will happen in a week or two...
 
Oh. I forgot to mention the IPAD issue. I got the dreaded overheating warning. As previously reported, I have my IPAD in a double articulated RAM mount. I really like how it is positioned. But on a hot day, in direct sunlight, it overheats.

After some research, I opted to order the X-Naut active cooling tray.
 
Charlie –

If you like the mini iPad mounting position with the double swivel you should try it in flight. I have two mini’s running ForeFlight in my RV-12 with large bubble canopy. Never had overheating problem in flight even on sunny summer day. Parking in the sun is different matter. I unclip iPads and tuck them under seat cushion so good-to-go when I return. Also better for prying eyes / light fingers. Overheating is from sun shining directly on glass surface when airplane is on the ground and no air movement. Not sure how much cooling fans will help.
 
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turbo oil leak

I had another "opportunity". My turbo developed an oil leak.

Upon teardown I see more wear on the bearing than on the turbine shaft seal. I have rebuilt it but I have not ran it after the rebuild.

I had a restrictor that measures about 1.5mm - 1.7mm. Since this is a journal bearing turbo, that "should" be about the right size. But admittedly my pressure seems to run on the high side, about 100psi at RPM. I could/might get by with a 1.0mm restrictor.

I called Kinugawa and talked with their tech. They thought the restrictor size was fine, given the application. But they recommended I add a in line filter which I did not have installed, but they are sending me one over night.

Here are some pics. input is welcome, but if you have comments please share your experience level for the readers. (not counting Ross of course who has years of experience with turbo applications).
 

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Restrictors are only required with ball bearings not journal bearings This is almost certainly the cause of the bearing distress here. Seen this before and it led to a forced landing for one guy, fortunately back on a runway with no airframe damage.

I've never run filters either and never had a bearing issue in running turbos for 40 years.

100 psi oil pressure isn't normal. I'd investigate that.

Be sure to index the compressor wheel with the turbine assembly as before when you reassemble. Some units are balanced as an assembly so this is the safest bet.
 
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Restrictors are only required with ball bearings not journal bearings This is almost certainly the cause of the bearing distress here. Seen this before and it led to a forced landing for one guy, fortunately back on a runway with no airframe damage.

I've never run filters either and never had a bearing issue in running turbos for 40 years.

100 psi oil pressure isn't normal. I'd investigate that.

Be sure to index the compressor wheel with the turbine assembly as before when you reassemble. Some units are balanced as an assembly so this is the safest bet.

Thanks Ross. Since I have an analog "needle" oil pressure gauge, it is hard for me to get a real accurate oil pressure reading as a slight movement at the top end of the range can make the increase pressure very hard to read. I probably should replace it with a digital gauge that is calibrated so I can get precise readings.

I did the indexing on the components.

I have had that turbo on the engine for about 2 years but only have about 40 hours on it. It is a bit of a mystery. I now see a suspicious looking spot in the picture of the turbine shaft seal "seat" that I did not see when I was looking at it while I had it out and inspecting it. (I was more focused on the seal and bearing). It might just be a glare/reflection, Ill have to wait until I get it running again. The shaft had virtually no play in it at all.

As far as the cause of the oil pressure being high, that is a real tough one to troubleshoot. The pressure drops to 75 at anything below 1500rpm. I could temporarily fit a digital unit on it to get a reading. I also have a sandwhich cooler with 1/8 npt ports that I could tap in to for some readings as well.....
 
taxi at KTDO and short video

I have the engine back running well with the new bearings on the turbo. I removed the 1.5mm oil restrictor in the feed line to the turbo. (thanks Ross). I have only ran it for an hour but all is well with the engine/turbo.

Here is a short video of my taxi at KTDO.

https://youtu.be/HjX0VjOhuOY

The only issue now is that I have a "leak" in the left side brake lines. I am going to post more details on this in the maintenance section of VAF. But to describe this briefly, I keep getting air showing up in the cross over line between the pilot and co pilot brakes. There is no fluid leaking anywhere.
 
Brakes

I swapped the brake cylinders left to right to narrow the cause of the air leak and sure enough the problem migrated. So....down until I get a brake cylinder kit from matco.
 
FIRST FLIGHT!

Today was the day. First Flight. All went well. Here is a link to a short video

https://youtu.be/gOC8upPFNpU

Here are a few pics too.

I know folks will want details but honestly, I only did 2 takeoffs and 2 landings for a total of about 0.6 hour. It was a fairly low ceiling so not much room to play. I honestly cannot answer most of the obvious questions like how fast did it go. So not much to report on performance at this point.

I was quite impressed with the thrust on take off. Very noticeable speed gain on roll out. I am using a 72" ground adjustable, 3 bladed solid carbon fiber prop made by Warp Drive.

I did see some the temps rise up to 198F on full power (5000rpm) climb out. My radiator inlet is small and the radiator lines take up a lot of the square inches of that opening, but I can easily enlarge it if needed.

I think I saw about 35" of M.A.P. at 4800 rpm. I thought it would be slightly higher but I am happy with this. I have no desire to push things at this point in the development of this set up. ( I am using a T3/T4 60/63 turbo).

I did feel a slight stumble on the 2nd take off which disappeared after a few seconds. Not sure about that. I will spend some time tomorrow looking over the engine area to see if anything looks amiss.

I also saw about 180-190f temps on the gearbox. That seemed a bit high but I will have to get with the manufacturer to see what they think.

As you will see in the pic, I have what I affectionally call "big feet" on the plane. I have 6.00 x 6 tires on the mains. No leg fairings or wheel pants. As you can expect, at this point this is not a machine intended for speed, per se. But I really like the view and stability those tires provide. Love them. I know some will gasp at the thought of those tires but I really like them.

That being said, I am very very happy with the flights.
 

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Congrats on the 1st flight!


Thanks Jeff, I appreciate that.

It definitely has been an - enjoyable - challenge for sure. At some points along the build it was more of a challenge than enjoyable, but I knew that going in to this from the beginning.

I am looking forward to a bit more time in the air to work out the inevitable squawks as they come up - and there will be some. Hopefully not big ticket items.
 
Big congrats Charlie! Few people know the feeling of accomplishment and satisfaction of flying with a different powerplant than the masses use. You've taken the longer path but think of all the things you learned along the way.

My gearbox oil runs at around 140F but has quite a bit of cooling air directed at the case.

Looking forward to updates as you fly more.
 
Thanks Ross,

I owe a ton of credit to SDSEFI and your help along the way.

Thank you for sharing your gearbox temps. This box only 8oz of 75-140wt mobil one synthetic in it. No airblast on it and no auxiliary oil cooler. Of course I need more time in the air to be able to really know the operating temps - both air and water.

The more I think about my "stumble" I reported, I am suspicious of (pre) detonation, which of course is critical. But, in hind sight, it happened at the end of a full power climb out, where temps are at their highest. It also went away as soon as I lowered the nose, and reduced power. It might have been the knock retard feature kicking in. I really don't know, I can tell you when that happened (at 500agl I was not focused on intake air temp or knock retard). Ill be pulling the plugs tomorrow to see how they look. My intake air temps have been very low since adding the intercooler. About 10-15 above ambient. But that was at lower power settings on the ground.

I do not have a dedicated source of cold air for my intercooler. So there is a lot of room for improvement in these areas.

Next flight will be a bit lower on the throttle esp on climb out. Probably 4200rpm.

I will keep folks posted on the progress.
 
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There is pre-ignition and detonation but no pre-detonation.

If you had pre-ignition, you'd likely have no ground electrodes on the plugs and quarter sized holes in the pistons in less than 10 seconds.

To minimize the chances of detonation, restrict the total ignition timing to about 25 deg at TO and climb power on 91 octane. With 100LL you should be able to run 30-32 safely. Ducting the intercooler properly will give you increased detonation margins as well. Try to avoid IATs over 160F.

Other possibilities are the AFR is too rich and you're getting into the rich misfire zone.

For now, good to keep climb power at or under 35 inches until you get more experience with the engine.
 
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There is pre-ignition and detonation but no pre-detonation.

If you had pre-ignition, you'd likely have no ground electrodes on the plugs and quarter sized holes in the pistons in less than 10 seconds.

To minimize the chances of detonation, restrict the total ignition timing to about 25 deg at TO and climb power on 91 octane. Will 100LL you should be able to run 30-32 safely. Ducting the intercooler properly will give you increased detonation margins as well. Try to avoid IATs over 160F.

Other possibilities are the AFR is too rich and you're getting into the rich misfire zone.

For now, good to keep climb power at or under 35 inches until you get more experience with the engine.

Ross,

I will attach a screen shot of (the top) of the ignition curve. It is as you suggest. Limit at 25degrees - but - with a 1-3 degree retard as MAP goes above 31 inches.

I have not seen any intake air temps above 130. But I will watch that more closely next flight, esp on take off.

I always use 92 octane.
 

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Good, this is even safer. Watch too little timing, can cause high EGTs though. You'll be down to 18 at high rpm and high MAP.

I limit my EGTs to 1400F.
 
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Good, this is even safer. Watch too little timing, can cause high EGTs though. You'll be down to 18 at high rpm and high MAP.

I limit my EGTs to 1400F.

Will do. I have not watched the EGT yet, but I doubt it is high at the settings I am using at this point, but I definitely will watch that.

I pay careful attention the Wide Band PLX meter to keep it between 11.9 to 12.3 as much as I can.
 
All engines, or only turbo and water cooled?

Or, maybe I should say what about us Lycosauras guys?

Auto conversions which typically develop more than twice the specific power as a Lyc. I've seen many piston failures on auto conversions where folks are in the mid 12s-13s AFR at high power. The Lyc is harder to hurt pistons on.
 
oil and air temps update

I flew for 0.6 hour today and learned a lot more about my set up.

Before I flew, I inspected all the sparkplugs. I did not see any signs of pre-ignition or detonation. In short they look good to me. I will attach a pic of one of them.

Also, I did a compression check. My numbers are 223,224,224,238. This was tested with the engine warm. I am very happy with those numbers.

The clouds lifted enough for me to circle the airport at about 2500ft. I intended to keep the power settings low. I took off and flew between 4000 - 4200 rpm.

At 4000rpm and 25 inches of MAP I saw roughly 125mph. Remember this plane as 6.00x6 tires, no wheel pants and no leg fairings. I am happy with that number for now.

The gearbox temps were 160-170 in level flight at 3500-4000rpm. I am happy with that. At 4200 rpm the gearbox temp crept up to 180F. In climb at 4000rpm, the temp rose to 190. I suspect it would have continued to get hotter at a steeper climb, or higher RPM. The manufacturer, Viking wants the gearbox back to check it over. Considering it is find at less than 4000rpm during level flight, I suspect it is working fine, but nonetheless I will be sending it back to them if I see a stretch of raining weather in the forcast.

The IAT (inlet air temp) was fine in level flight, about 130F at 4000 RPM but again, it started to rise during a climb out and got as high as 169F when I leveled off to cool down the IAT. Fortunately, this is probably and easy fix. My intake air filter - now - is mounted directly on the compressor inlet flange. Easy to create a intake over to the cold side of the egine. Plus I have yet to install a scat tube to "feed" in the intercooler box with ram air. That will also do wonders to cool down the IAT. Some will wonder why in the heck I did not do this in the first place.....because.....I really want to see exactly how much these mods will affect the temps. So I will do these two improvements separately so I know the impact each of them as individually.

Engine coolant temps. They do climb to up to 198F but once leveled out at 4000rpm they stayed at the 185F thermostat temp. Which is really amazing considering how small the inlet scoop is. I may still enlarge it to reduce temps on climb out on hot days but not after more testing.

But in short, the plane is a blast to fly and is doing very well in my book.
 

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All seems reasonable for now. Will be interesting to see how the planned mods affect the temps. Plug looks nice.
 
modifications

The modifications that I will be working on are:

1) Blast tube to the gearbox. My first thought is to put a 1.25" aluminum tube (what I have laying around) through the cowl, aimed directly to the bottom of the gearbox. My thought is that since the lower gear of the 3 gears is turning the fastest, it is the gear that would benefit from cool air the most.

2) Add ducting to the compressor on the turbo to route it over to the cooler side of the engine.

3) Add ducting to the intercooler shroud. I made it so it has a 2-1/2 flange on it but I just wanted to see the temp numbers without it so I knew how much benefit the ducting provided in lowering the IAT.

4) Add a thin sheet of aluminum to the top (inside) of the cowl above the turbine to protect it from radiant heat. This will have a 3/16"air gap which does wonders for protection from radiant heat. The cowl was a bit warm but not too bad. But considering I have only been running at 25" of manifold most of my short flights, I suspect I will really need that heat protection once I am able to increase performance.

My altimeter is also not working properly, but I also get altimeter data from my IPAD - Foreflight.
 
Charlie

I’m looking at your spark plug photo and wonder if you might benefit from using a high-temp Silicon Thermal Paste instead of anti-seize on the plug threads. Rotax uses Silicon Thermal Paste to help conduct heat into the water-cooled cylinder head. The paste fills in the void on the backside of the threads when the plug is tightened.

You can search Rotax 912 spark plug paste. Also this link… https://electricmotorglider.com/wp-content/uploads/2016/03/Spark-Plug-Part-1-Web.pdf

 
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Charlie

I’m looking at your spark plug photo and wonder if you might benefit from using a high-temp Silicon Thermal Paste instead of anti-seize on the plug threads. Rotax uses Silicon Thermal Paste to help conduct heat into the water-cooled cylinder head. The paste fills in the void on the backside of the threads when the plug is tightened.

You can search Rotax 912 spark plug paste.

Jim,

It is an interesting article. Thanks.
 
another Honda RV flhying before mine

I think I may have said in the past that I did not know of anyone else who is flying with a Honda RV. Of course there are many with the subaru and some with Mazda rotaries.

But José Pedro Almeida has a 1.5 Honda Fit engine produced by Viking Aircraft in his RV9 and his first flight was about 4 years ago. You can see that here

https://www.youtube.com/channel/UCqra3XaCO4gbHAqhDV9zyGQ

So, Shout out to Pedro. He has about 130 hours and about 90 flights in his RV9A and he reports all is well.
 
more performance numbers

I flew for 1.5 hours today after several minor changes, such as:

1) Adding ducting that moved the air filter off of the turbo compressor over to the cooler side of the eingine.

2) Added a 1-1/4" aluminum tube in the front of the cowl so it blasts air directly on to the bottom of the propreller gear box gear.

3) Expanding the front of the radiator scoop inlet 0.5"

The results are"

1) Inlet air temp down from the upper range of 160F down to about 120F in climb and down to 100F in level cruise at 4000rpm at 25-27map.

2) The gearbox was 170F in level cruise and 185F on climb. But again, this was at only 4000rpm.

3) Engine temp stayed at the 185F thermostat temp. I also have another coolant temp sensor on the cold side of the radiator and it was 135F on cruise and 150F in climb.

Im seeing 125mph at 4000rpm and 25" of MAP. With a climb pitch and bare and big gear/tires, I have no complaints. I will be adding some more pitch as time allows and possibly adding gear leg fairings. but not after much more testing.

I have experience a slight "stumble" in the engine a couple of times. It was so short it is very hard to describe an impossible to corelate to anything.

ADDED: I typically see about 1000F EGT and 9-11psi on the engine coolant. Coolant will get to 15psi if I push it harder.

Much more flying to do. I have other non-engine challenges but I won't go in to those because its outside of the focus of this thread.

Feel free to ask questions if you want.
 
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The temp delta on the rad is really good.

EGTs seem really low if you're measuring at the ports, suggesting the mixture is maybe much richer than you think (AFR reading may be incorrect). This could be causing a rich misfire at times.

If you are measuring EGT post turbo, the temps would be more in line with what I'd expect due to the temp drop across the turbine.
 
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The temp delta on the rad is really good.

EGTs seem really low if you're measuring at the ports, suggesting the mixture is maybe much richer than you think (AFR reading may be incorrect). This could be causing a rich misfire at times.

If you are measuring EGT post turbo, the temps would be more in line with what I'd expect due to the temp drop across the turbine.

I do think the delta drop is credible because I did check the accuracy of the temp sensors and gauges before installing them. So yes, I am happy with that for sure.

I am going to attach a close up pic of my "field" modification on the inlet of the radiator scoop. As you can see I literally cut down the bottom of the leading edge of the scoop and bent it down 0.5" and riveted a brace to held it there. Crude, but effective.

This mod did two things. 1) It increased the size of the opening. 2) Probably more important, it repositioned the lower lip of the inlet to be streamlined with the oncoming air. I should have intentionally done this from the beginning, and probably further back so the air entering the scoop would be stabilized for a bit longer period before the divergence occurred.

I am going to watch the temps during higher performance runs before I "putty" it in and make it look nice. I may expand this a bit more if needed. ,
As far a the EGT temp - A/F ratio goes I am interested in your comment. But , yes, the EGT is about 8-10 inches after the turbo. It would be interesting to get some TIT too but that would be a bit more work to tap in to a turbo mount.

I do see a difference in the PLX WB meter and the O2 number in the SDSEFI gauge window. I can remember for sure but I think the SDSEFI is about 0.5 more rich. But, it is also important to note that the SDSEFI is getting its numbers off O2 wiring. (as I am sure you know).
 

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Ok, 1000F after the turbo probably means 1200-1300 before which is in the ballpark of where I'd expect it.

I think you have an EM-4 ECU. If you have V17 software, there are a couple choices for WB voltage scales. Check and see which your PLX uses. Some are 0-5 some .5 to 4.5.

Best to believe the PLX gauge for now if you have their display.
 
Ok, 1000F after the turbo probably means 1200-1300 before which is in the ballpark of where I'd expect it.

I think you have an EM-4 ECU. If you have V17 software, there are a couple choices for WB voltage scales. Check and see which your PLX uses. Some are 0-5 some .5 to 4.5.

Best to believe the PLX gauge for now if you have their display.

Thanks for the info. Good to know. I think they're real close. Good for now.
 
engine stumble

I have a whopping 6 hours on the hobbs now.

This are going well. I am fairly confident I need more pitch on the prop. I will probably do more testing before increasing from 20 to 23 degrees. But it wont be long.

I also believe I know what the cause of the engine stumble. While I have not been able to recreate it, I believe it was my blow off valve cracking open when I exceeded the setting. I took the plane up to 8000ft today to see what the cruise was at altitude, but unfortunately the gearbox just gets too warm (over 180F) when I go past 4500 rpm. today when I was at 8k I took it up to 37 inches MAP to see if the BOV would crack open but it did not. 38" is my self imposed MAP limit.

Since the gearbox was already creeping past 185F I decided against pushing it any higher. The maker of the gearbox (Viking) wants it back to look it over and I am going to send it too him as soon as I get a good stretch of rainy weather but until then I am going to take it easy and get more hours on my Phase1.

I feel confident I will be adding an oiler cooler to the gearbox. But that is another rainy day project. I may also add a 2nd blast tube to the box.

Moving the air inlet over to the cold side did wonders. I rarely see it over 120F. When I actually duct a blast of air over to the intercooler shroud I am sure it will drop at least another 20F. Another rainy day project.

Charlie
 
Good progress Charlie.

I might suggest removing the BOV altogether. They don't serve any useful function, are just dead weight and another possible liability. I've never used one in 40+ years of turbocharging engines including race stuff.

With regards to the gearbox temps, what kind of OATs are you flying in?
 
Compressor Surge?

Charlie/Ross I have not read the specifics of this "stumble" condition, but be aware it could be compressor surge. That is when the exit plenum air pressure builds beyond the compressors ability to move adequate mass flow and there is back flow across the compressor for an instant. You would need to look at the compressor maps to see if it is getting close to the surge line, and even if close it is no guarantee that it is ok.

I have been close to large diesels that had surge issues in a test cell and the blowback will knock your hat and glasses off 6 feet away. It can eventually break something if left to perform that way for extended events. Typically recirculating compressors extend that margin.

Not saying the BOV is not the problem or is needed, that is another issue entirely.
 
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Ross, Bill,

OAT as varied between 60F to 35F.

I will have to dig out some paperwork for those turbo numbers after I get back from the airport tonight.

Got the comment on the BOV. The stumble has only happened 2 may be 3 times for just a second or two. I have not experienced it again. Even after going up to 37ish MAP, and 5000rpm.

The first time it happened I was climbing and just after turning in to the crosswind leg. When it happened I immediately reduced power and lowered the nose and headed back to the airport. It went away immediately.

The second time I was on downwind. Again it went it happened I immediately reduced power and it went away. I wish I could tell you what MAP I was at when this happened, but I cannot. I was not looking at the MAP GA when it happened and I was more focued on flying. At that instant. It might have happened when I reduce power, I just cannot say. I will do some more testing in the next few days.

You guys have 1000 time more experience that I do, but for what it is worth, I think BOV cracking open, or compressor surge may be it. If compressor surge happens when you back off of a "higher" MAP settings it may be the cause as well.

I do appreciate the help, thank you.
 
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I found your earlier post listing the wheel inducer and exducer sizes and turbine housing A/R. If those are the same now, that would indicate these trims. In which case, you should be nowhere near the surge line in flight which is at about 40hp eq mass flow at 1.1 pressure ratio.

Climb or cruise power puts you miles away from surge, in the middle of the islands around 65-70% compressor efficiency.

If you pull the throttle back slowly, any chance of surge is minimal as the N1 rpm drops immediately.

Surge will manifest itself with chirping or stuttering sound as the air comes back out the through the compressor blades. Intermittent surge doesn't hurt anything but I've never encountered it in my plane in 18 years of flying it with similarly sized components. My turbine A/R is .82 on a 2.2L engine. The .63 should be fine for your smaller engine.
 
Thanks for checking that, Ross, it seems it is all ok. Modern compressors have more margin and with compressor housing recirculation, makes it even less likely. Surge on large turbos on diesels sound differently than you describe, sometimes like a heavy POP as the air reverses through the compressor. The engine never changes, boost drops a little and recovers in an instant.
 
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Thanks for checking that, Ross, it seems it is all ok. Modern compressors have more margin and with compressor housing recirculation, makes it even less likely. Surge on large turbos on diesels sound differently than you describe, sometimes like a heavy POP as the air reverses through the compressor. The engine never changes, boost drops a little and recovers in an instant.

The V trim compressor is very old, maybe something like 40 years now but can still work well if matched right.

Surge on automotive sized turbos is usually encountered only on rapid closed throttle assuming they are reasonably well matched and the turbine A/R is not too tight. I've only seen one sustained instance in a car with a way too big compressor tied in with a way too tight A/R turbine housing. The engine refused to accelerate at all above 3000 rpm regardless of throttle.

With regards to BOVs, none of the professional IMSA, Trans Am or F1 turbo cars back in the pre '90s were ever equipped with them to my knowledge and they serve no useful purpose on most aircraft where you never go from full power to idle in less than 1 second. Never used on Sport Class Reno racers where MAP may exceed 100 inches.

If it ain't there, it can't fail... My 2 cents.
 
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