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Caleb lesher SDS EFI RV-7A

Norcalrv7

Well Known Member
------------------July 2017. Photobucket has terminated their free picture hosting. I apologize while I transfer photo hosting companies!----------------


After removal of my Subaru engine, my fully Electronic fuel injected IO360 is alive. I am using SDS EFI's latest cylinder mount injectors, and dual coil packs for ignition. I have Fly EFII's bus manager system with dual batteries, and dual Walbro fuel pumps. First start occurred yesterday at last!

While a "traditionalist" airport mechicic watched in amazement, it started on the second blade, and I was quickly able to tune fuel mixtures on the panel mount tuner to a buttery smooth idle.
My experience with SDS EFI has been excellent. Beautiful high quality cnc parts, and very quick and personal help via email from Ross.

With a background in EFI cars and tuning, I am excited to get my RV7 back in the air and begin exploring the possibilities!
12238289_1119560538061682_8171434958043099260_o by Caleb Lesher, on Flickr
20150108_075007 by Caleb Lesher, on Flickr
 
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Congrats Caleb. Look forward to your impressions and numbers on the EFI Lycoming vs. your old Sube.
 
Subie Replacement

After removal of my Subaru engine, my fully Electronic fuel injected IO360 is alive. I am using SDS EFI's latest cylinder mount injectors, and dual coil packs for ignition. I have Fly EFII's bus manager system with dual batteries, and dual Walbro fuel pumps. First start occurred yesterday at last!...

Did you have an Egg Subie; or develop your own? How many hours did you fly it, prior to beginning the replacement? I for one would also enjoy seeing some pictures of your injector boss installations, where you located the coils, etc. Fly safe!

Doug

RV-9a Mazda 13B/FWF
 
Did you have an Egg Subie; or develop your own? How many hours did you fly it, prior to beginning the replacement? I for one would also enjoy seeing some pictures of your injector boss installations, where you located the coils, etc. Fly safe!

Doug

RV-9a Mazda 13B/FWF

Hi Doug. My airplane was originally a Eggenfellner engine package. The airframe itself flew 692 hours under Subaru power before I removed it. This was accomplished however with several different engine and gearbox combinations.

Caleb
 
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https://photos.app.goo.gl/maL7F6B37BIDMfK13
 
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I used Ross's Throttle body, and didn't want a scoop, so this is what I came up with. I Used a metal piece of aluminum tube in the shape I wanted, then carved a foam block for a transition. It holds a K&N Filter in the left cowling baffling.

20160818_154630 by Caleb Lesher, on Flickr

20160818_162819 by Caleb Lesher, on Flickr

20160819_123750 by Caleb Lesher, on Flickr

20160819_133916 by Caleb Lesher, on Flickr

20160824_194520 by Caleb Lesher, on Flickr

20160824_194524 by Caleb Lesher, on Flickr
 
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Very interesting that you are using the primer boss holes for the injectors. Those have even a better shot at the valve than the std Lycoming location on top, but are tough to cowl up. I'd use that location if I could but the Rocket cowl is just too tight. Looking forward to hearing how they work in service... I may end up blistering my cowl for clearance.

Clever solution for your airbox, but I suspect you are going to suffer some duct losses with that long, parralel wall tube. I'm sure it will run just fine, but I think you are leaving some "free" power on the table.
 
Very interesting that you are using the primer boss holes for the injectors. Those have even a better shot at the valve than the std Lycoming location on top, but are tough to cowl up. I'd use that location if I could but the Rocket cowl is just too tight. Looking forward to hearing how they work in service... I may end up blistering my cowl for clearance.

Clever solution for your airbox, but I suspect you are going to suffer some duct losses with that long, parallel wall tube. I'm sure it will run just fine, but I think you are leaving some "free" power on the table.

While I was looking at the Cylinders, I saw that the primer hole had (what looked like at least) a better angle for the intake valve compared to what I have seen in cars. Since I am using a prop extension and a long cowling, I have the room to the try it and see how it works out. I am a little concerned about their temperature in this location. I plan on doing some measuring, and possibly building some blast tubes for them here. I will report back!

Some of the earlier pictures also show a fuel rail loop that went all the way from one side of the engine to the other. I think this would theoretically be a better fuel rail design, but was too messy/complicated for my liking. According to Ross, there haven't been any vapor lock issues with the individual lines, plus they sure look nice.

The intake was one of my first attempts at composites. I am happy with how it turned out, But as you mentioned its shape it not optimal. Its on the list of possible improvements for the future!

Thanks for the interest.

Caleb
 
I believe Caleb's induction tube will be fine here. The bends are smooth and the inside area is larger than the TB aperture minus the shaft and blade area by a fair amount. The TB already has a lot more area than the Marvel carb venturi. You can always see what MAP is vs. baro to find out if there is a loss here at WOT and high rpm.

Dave Ander's temperature testing of his injectors mounted under the cylinders found them within acceptable ranges but more temp data is always good as this location is slightly different. Have to watch the IR off the exhausts down low.

I see your earlier pix showed a loop type rail system and later the individual lines.
 
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I didn't mean to imply that the induction tube setup is going to be a performance detriment (compared to the Vans setup), only that is is not "optimal". Truth be told, the difference between this setup and "optimal" is likely very slight, perhaps immesurable, but is likely there. You do have my respect for developing and executing a solution however. Nice to see you didn't throw in the towel just because the part you needed wasn't available from a vendor.

I would suggest a small drain hole at the bottom of the tube if you don't have sniffle valves though. That airbox looks like a great funnel for water!
 
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Is that 3 batteries on the firewall?

Sure is... My airplane turned out quite tailheavy. After removing the Subaru. I moved everything as far forward as I could, and added a prop spacer, but was still looking at exceeding the aft limit with 2 passengers and bags. I decided to add a 3rd standby battery on a switch to my critical bus instead of adding lead. Not sure why my airplane is so tailheavy. I'm guessing a combination of the lightweight 360(no mags, carb, or accessories) and the fact that my plane was painted clearcoat.... And lots of it by the original builder.

Caleb
 
Sure is... My airplane turned out quite tailheavy. After removing the Subaru. I moved everything as far forward as I could, and added a prop spacer, but was still looking at exceeding the aft limit with 2 passengers and bags. I decided to add a 3rd standby battery on a switch to my critical bus instead of adding lead. Not sure why my airplane is so tailheavy. I'm guessing a combination of the lightweight 360(no mags, carb, or accessories) and the fact that my plane was painted clearcoat.... And lots of it by the original builder.

Caleb

I don't claim to be an authority on the -7A, but a 360, a Hartzel on a spacer and 3 batteries on the firewall... That just doesn't pass the giggle test.

Are you confident in the W&B? Maybe some other -7 owners can jump in and set me straight, but without a smoking gun driving weight in the tail, it seems more likely that its a simple math error.

Not being critical, just seems like a red flag.
 
I moved everything as far forward as I could, and added a prop spacer, but was still looking at exceeding the aft limit with 2 passengers and bags. I decided to add a 3rd standby battery on a switch to my critical bus instead of adding lead.

Seems like a PC680 at 48" aft of datum would have moved the CG about 1/2", tops. Am I wrong? Don't have a 7A W&B spreadsheet handy.
 
I've been hoping to find a brick of lead in the tail... But no luck yet. I'm almost embarrassed to say how heavy it is! I weighed it on some borrowed car scales. 1168 total. 452 left main, 445 right, and 271 on the nose. The plane has at least 3 layers of paint on the exterior, and the inside of all the structures were painted heavily by the builder. Maybe someone has some data about cg before and after paint?

Caleb
 
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The 6 cylinder Sube is no lightweight. Paint looks better than than a lump of lead although maybe not as efficient.

This weighs about the same as my 6A. I have one 680 between the rudder pedals and another similar sized battery just aft of the baggage bay.
 
I've been hoping to find a brick of lead in the tail... But no luck yet. I'm almost embarrassed to say how heavy it is! I weighed it on some borrowed car scales. 1168 total. 445 left main, 452 right, and 261 on the nose. The plane has at least 3 layers of paint on the exterior, and the inside of all the structures were painted heavily by the builder. Maybe someone has some data about cg before and after paint?

Caleb

That nose seems awfully light!

My own 7A numbers are MLG 444/442, NLG 302, 1188 total (chubby girl I know).
Other examples of 7A's with CS props I've weighed:
439/436/292
432/444/309
428/425/306
 
That nose seems awfully light!

My own 7A numbers are MLG 444/442, NLG 302, 1188 total (chubby girl I know).
Other examples of 7A's with CS props I've weighed:
439/436/292
432/444/309
428/425/306

Interesting. My girlfriend already scraped out all of the sound deadening behind the seats. (She's a keeper) Maybe I'll look harder for a hidden piece of lead. It would be interesting to see the weight difference of a painted vs non painted tail.

Caleb
 
This project started when I bought a low time "runner" IO360 from a salvage yard that will go nameless. The plan was to install Ross's EFI components and fly. I decided to disassemble it first before bolting it on. good thing I did. I found 2 broken piston rings, and badly corroded cam. So into the bottom end I went, only to find a scored crankshaft, that had already been ground to minimum undersize. The only thing of value left was the case, which luckily passed inspection at Divco. For a guy in his late 20's, I did the only logical thing. I worked overtime, lived with roommates, and ate lots of ramen noodles to pay for all the new parts. Luckily the airplane was still flying under Subaru power, so It was easy to take my time and save for the parts I wanted. A new crank, cam, sump (forward facing) and 4 new cylinders later, I got to put it all together with the watchful eye of my mentor mechanic. I have rebuilt several car engines, but this was my first Lycoming. Aside from the price tag for the parts, I found it enjoyable and straight forward. Since I can't say I built my RV, I figure the next best thing is to say I built the engine!

2016-03-14 11.37.09 by Caleb Lesher, on Flickr

2016-03-17 14.16.28 by Caleb Lesher, on Flickr

2016-03-18 12.29.07 by Caleb Lesher, on Flickr

2016-04-06 08.32.22 by Caleb Lesher, on Flickr

2016-04-06 14.09.00 by Caleb Lesher, on Flickr

2016-04-11 12.52.00 by Caleb Lesher, on Flickr

2016-04-12 16.03.14 by Caleb Lesher, on Flickr


2016-04-15 13.51.43 by Caleb Lesher, on Flickr
 
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Doesn't add up to 1168. Which value needs correction?

Caleb, it's a pleasure to see a nice, clean, well organized engine build.


My mistake, nose is 271 and 452/445. Thank you Dan! I hope it runs as good as it looks.

I decided I'm going to Re-level, weigh, and measure tomorrow. I have accomplished different parts of the procedure at different times with the plane being level/not level. Maybe I'll take the tail fairing off again and look for some extra weight too :)

Caleb
 
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One of the more critical processes with the installation of the SDS EFI system is the hall sensor mounting and signal magnets. Ross sent me everything I needed to lay out and mount the signal magnets on my own. Unfortunately, the Starter ring gear support that came with my engine had the smaller pulley style. The larger is needed for the SDS system I was able to source one with a bad ring gear that I found that it was off of a O320-E2D. The only difference was that it had smaller holes for the crankshaft bushings. I was able to lay out the holes, and ream them to the proper size. One word of caution when using this technique. The 320-E2D (and possibly others) has a differently indexed layout than the IO360 engine. There is one larger hole marked with an "O" that should match the crankshaft. This "O" was in a different position relative to the TDC marks on the original ring gear support.

Modifying the 320 ring gear to fit the 360, and tapping for magnets
2016-04-08 13.22.18 by Caleb Lesher, on Flickr

2016-04-11 10.06.21 by
Caleb Lesher, on Flickr

I have a special container of granddad's safety wire from the 70's that gets used on important things, like the hall sensor mount shown here
20160607_174352 by Caleb Lesher, on Flickr

The exiting boxes are starting to arrive!
20160303_123257 by Caleb Lesher, on Flickr

Cheap meal to save money for more airplane parts :)

20160705_213003 by Caleb Lesher, on Flickr
 
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I elected to make my own wiring harness for the ECU, so I could route the wires exactly how I wanted them, and also have the personal experience of the wire layout. I used the provided plugs and pins, with adhesive lined heat shrink, and mesh type wire loom. With the proper crimp tool and pins, I found the wiring process enjoyable.

I also switched from my original idea of a loop style fuel rail to the individual lines and fuel block from Ross shown here.

20161112_105303 by Caleb Lesher, on Flickr
 
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While I had the firewall completely torn apart, I had some work behind the panel to complete also. I found a good deal on a 10" HXr efis to replace my 8" model. One thing led to another, and before long I had also purchased a used Garmin 430W to replace my 480, and a Garmin GTX345 transponder with ADS-B in and out. I also added a seconds SL40 COM. It was winter anyway, so why not get it all done now.


I built a custom heater plenum with attachments for the defrost vents to replace the heater core from the Subaru.

14440969_1379667885384278_6218592851467915973_n by Caleb Lesher, on Flickr

I also made a lower panel cover plate to cover all the old switch holes, and to add a propeller control cable.

At this point I was wondering if this was a bad idea.
13731538_1292859554065112_2627549356242851577_n by Caleb Lesher, on Flickr


20161106_214236 by Caleb Lesher, on Flickr

A few months later, and it all works!

20161107_154353 by Caleb Lesher, on Flickr

After:
0823171011 by Caleb Lesher, on Flickr
 
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Induction tube

You will have a very small frictional loss from that length of tubing compared to a larger snorkel. But it probably very small, since, as Ross said, your tube is larger than the throttle body throat.

I am very curious, however, how you got the aluminum tube out after you wrapped it.
 
You will have a very small frictional loss from that length of tubing compared to a larger snorkel. But it probably very small, since, as Ross said, your tube is larger than the throttle body throat.

I am very curious, however, how you got the aluminum tube out after you wrapped it.

1 ply of fiberglass, then I cut it lengthwise, peeled it off, and ca glued it back together before adding 2nd layer

Caleb
 
The photos of your journey are great. Appreciate you posting them here. Nice clean layout on every facet. Might help others following in your footsteps.
 
The photos of your journey are great. Appreciate you posting them here. Nice clean layout on every facet. Might help others following in your footsteps.

Absolutely correct statement Ross.

Caleb------great work.:D
 
New weight and balance numbers are in. Looks like I needed to more accurately level the aircraft before looking at numbers. 447/433 with 294 on the nose.

Caleb
 
Your write-up reminds me of one of those television reality shows where they rebuild a home. First you see the tradesmen starting to work then they take a commercial break. When they come back after commercial, the home is re-plumbed, the finish work is in except for a final piece of molding, and they are ready for the "Move-that-bus!" moment. I'm jealous. ;-)

~Marc
 
New weight and balance numbers are in. Looks like I needed to more accurately level the aircraft before looking at numbers. 447/433 with 294 on the nose.Caleb

My spreadsheet says you're 1" forward of the rear limit at a reasonable "worst case" loading; minimum fuel (5 gal), a pair of 200 lb guys in the seats, and 50 lbs in the baggage area.

You could remove all three PC680's and install two EarthX ETX680's (-38 lbs at 56", moment -2128); the CG at the above worst case would still be 0.3" within limits (CG 86.5, limit 86.8). Check my numbers of course.

For sure you don't need a third battery. Take it out and save about 16 lbs with wiring, assuming you actually have confidence in the Bus Manager architecture. If you're not comfortable removing it, perhaps it's time to change your electrical system. I can't do fault analysis without knowing more about wiring details for the third battery, but I suspect it doesn't really help maintain a live engine.
 
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I like the automatic features of the bus manager, but also see it as a potential single point failure. The 3rd backup Batt is a very simple backup if all else fails. Maybe I'll put some time on the airplane and consider removing it, or going to the lithium batteries. I haven't looked at lithium batteries in depth until now, but the numbers (except for price) sure are awesome! I am also running 1 alternator at the moment. Maybe as the bank account allows, Ill go to dual alternators and dual lithium batteries.
 
I like the automatic features of the bus manager, but also see it as a potential single point failure. The 3rd backup Batt is a very simple backup if all else fails. Maybe I'll put some time on the airplane and consider removing it, or going to the lithium batteries.

Do a wire by wire analysis of the Bus Master primary power architecture. Add the additional battery, switch, and feed wiring, and include it in the fault list. Then make a logical decision. See posts 58 and 63 here:

http://www.vansairforce.com/community/showthread.php?t=146753
 
Nearly a year after starting this Subaru-Lycoming conversion, my RV-7a took to the sunny skies over Eureka, CA. The engine ran silky smooth without any hiccups. CHT's stayed in the mid 300's, and I ran the engine at 25" and 2500 RPM at about 11:1 AFR for break in. After the flight I cut the filter open, and found nothing abnormal. Success! Now to fine tune all my fuel and timing values in SDS.

Using Ross's software on my laptop to see realtime engine data. Tuning my fuel tables here
0307171148 by Caleb Lesher, on Flickr


One More test run
0228171753a_HDR by Caleb Lesher, on Flickr

Ready to fly!
0328170752a_HDR by Caleb Lesher, on Flickr


0310171127a_HDR by Caleb Lesher, on Flickr

Success!
0310171125a by Caleb Lesher, on Flickr
 
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Congratulations! I am jealous,as I have my Rv4 w 2.5 suby waiting for me to get back to NY from Fla. AW, Taxi testing fuel & cooling no leaks,ready for good preflight and then fly.Tom
 
Had some smooth weather today, So I took advantage of it do so some Individual cylinder trim testing. This is a freshly overhauled parallel valve engine with Lycoming Horizonal sump, and some custom intake tubes from Vetterman. Some initial numbers look like cylinder trims as follows:

1= -2%
2= +3%
3= -2%
4= +2%

These settings resulted in a GAMI spread of .2GPH for my setup.
Not surprised to see the wide variance due to the poor intake sump design.

I plan on doing more testing to verify this data is repeatable.

I made a nice spreadsheet on my laptop to graph my EGT data in realtime, and make adjustments in SDS without having to land and pull datalogging information from the EIS. And yes, that is a green cushon from the hangar couch in my copilot seat that serves as a laptop mount :)

0328170827_HDR by Caleb Lesher, on Flickr

Caleb
 
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I initially missed the fact that you have adapted the "tuned" 200 HP sump to your parallel valve engine. I think thats a great idea as I'm doing the same with my Rocket, but I am going to fly with the original 260 HP sump for a while then do the switch. On paper, the factory tuned sump is vastly superior to the standard version due to increased plennum volume, runner approach angles and runner length. The proof, of course, can best be verified with testing.

You are seeing a bit of a "GAMI spread" with this new intake, but I suspect you would see a bunch more variation with the stock sump. As stated above, I intend to fly and tune the stock sump, then do the switch and document any change. I have set up the stock sump with a raised throttle body adapter so that it will be the same height as the tuned sump - meaning that I will not have to change any other performance variable except the sump itself.

21jnfxf.jpg


11ltuep.jpg


It is a shame (but understandable) that you did not have any before and after info with this sump, but hopefully I will be able to fill in that blank in a few months.
 
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Wow looks very nice! I keep forgetting that my sump/tubes/cylinders are a hybrid design. The Horizontal sump certainly has more volume than the stock -B1E Rear induction sump I started with. I'm not sure the model number, but mine is NOT the style where the tubes cross each other inside the sump with bell style intakes. My performance numbers seem to be somewhere between the 180 and 200 HP numbers, and my airplane is 100lbs heavier than It should be. Would be interesting to see how much of a gain the sump, ram air, and EFI all add up to individually.

Caleb
 
Wow looks very nice! I keep forgetting that my sump/tubes/cylinders are a hybrid design. The Horizontal sump certainly has more volume than the stock -B1E Rear induction sump I started with. I'm not sure the model number, but mine is NOT the style where the tubes cross each other inside the sump with bell style intakes. My performance numbers seem to be somewhere between the 180 and 200 HP numbers, and my airplane is 100lbs heavier than It should be. Would be interesting to see how much of a gain the sump, ram air, and EFI all add up to individually.

Caleb

So the standard B1E sump looks much like my D4A5 sump- very little plenum volume, tortured runners and all bathed in hot oil.

540sump_zpsm7dxhs5t.jpg


But yours appears to be the cold air sump, much like this:

xnytzs.jpg


If you do not have the individual tubes extending into the plenum, what do you have?
 
Some initial numbers look like cylinder trims as follows:

1= -2%
2= +3%
3= -2%
4= +2%

These settings resulted in a GAMI spread of .2GPH for my setup.
Not surprised to see the wide variance due to the poor intake sump design.

Plus or minus 2% is the standard flow tolerance for off-the-shelf electromagnetic injectors. The restrictors we use in constant flow systems are probably similar. Either can be flow-matched into sets on a bench.

Clearly variation exists in mass airflow too, and note there's more to that than just the sump. However, reality is random variation in both fuel and air delivery.

Install a set of flow matched injectors, then look at the peak spread.
 
I purchased the Lycoming "bat wing" style sump during my engine overhaul. looking back at the pictures it is stamped "74664". It appears in this style sump, the intake tubes normally extend into the sump to form the bell mouth tubes. My intake tubes (made by Vetterman) end after the 0-ring seal.

I red one thread a while back about someone experimenting with intake tube length optimization, but never heard anything specific, anybody have input here? I am more than happy with my mixture distribution. As DanH said, even 2-3% is acceptable variance with electronic injectors.

Sump visible in lower left

2016-03-14 11.37.09 by Caleb Lesher, on Flickr
 
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Before we had the mixture trim option available, users would swap a "cold" injector to the "hot" hole to see if the injector was causing the issue. I did the same in my Subaru engine. Never saw any significant change, indicating the injectors we use are typically flow matched to something less than 1%.

When I used to flow test injectors a lot of years back, I rarely saw more than 1% variation on Bosch injectors. Less than that was hard to read on the graduated cylinders and was the within experimental error of the test rig.

1% is truly splitting hairs and makes no significant difference to engine performance.

Others in the past here have disputed the large GAMI spread present on some sumps is due to airflow imbalance and when I called them out on the tailored Bendix type injector size used to fix the imbalance (calculated area), they suddenly became silent.

There have been a couple large threads on these matters here on VAF. I'll repeat what I said then:

1. Equal airflow to each cylinder is ideally what we want. This results in near equal hp being produced by each cylinder, the smoothest possible running and all cylinders to peak at nearly the same time so we can lean all to nearly the same AFR.

2. Tailoring mechanical injector sizes or electronically altering the pulse width on EFI injectors to match the airflow imbalance present is a partial patch for the true issue. It's clearly better than not doing anything.


The EFI trim option is a huge time saver- it simply doesn't care whether the AFR imbalance is caused by airflow or injector fuel flow variations- you don't need to get out of the cockpit to correct your AFR in each cylinder and you can do it at any power setting, not a fixed, relatively narrow range as with mechanical FI. Customers are embracing that technological leap along with the other demonstrated advantages of EFI like no hot start or poor idle issues.

We've seen the flight testing by Dave Anders (with flow matched cylinders) and others using our EFI to trim each cylinder in flight at any rpm/MAP combination to within 1% as being able to extract the best from their installed intake system. In Dave's case, at extremely low power settings, he was able to still balance the cylinders down to impressively low fuel flows with very decent TAS numbers. Not everybody flies like this but it shows the superior fuel metering capability of EFI over legacy mechanical FI systems which don't work well in this regime. This is really as good as it gets until someone produces the perfect Lycoming sump with equal airflow at all rpm/MAP combinations.

I applaud the experimentation of Caleb and Michael here. We'll learn some more about this fascinating subject.
 
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