C-box ratios

[akflyer 1427]

Mine came with 2 metal washers on the shaft and they boogered up the threads over time and cause me to loose the ability to adjust the pitch. I have a new one and have not yet installed it. Make sure there are no metal washers on the threaded portion on the shaft.

Herman, I am not sure just how far you were running the pitch to snap that shaft. Remenber, you are only talking about needing to change the pitch a few degrees inflight, not running it from stop to stop. I doubt I ever use more than a couple quick blips of the toggle switch, you never need to hold it one way or the other more than a second MAX.

[ChrisBolkan 130]

Chris

I just noticed that you replyed to my question 8 days ago.Sorry.

Yes the jack screw broke within minutes of installing and everything was wired exactly as IVO sent the switch and breaker.

I should be getting the repaired IFA motor and jack screw back any day.

Today I started to wire in the poly switches and noticed that your switch wiring diagram differs from how IVO sends the prewired switch

as to where on the switch the power and ground and slipring connections are.

IVO sent the switch with power from the breaker and ground going to the middle pair of terminals of the 6 terminal switch.

You have the slipring wires to the motor originating from the middle pair.

I am trying to figure out why I had a jack screw failure so soon.

Hopefully the polyswitches will offer better protection and faster reset than the IVO breaker.

Do you have a Lycoming powered Magnum?

Does it have an IVO IFA prop that you developed the polyswitches on?

Thanks Herman

Hi Herman,

The switch is wired a bit differently in order to allow one polyswitch to work at each end of the travel of the prop. If you follow the current flow through the switch and polyfuses in the different switch positions, you will see that it makes sense, but wouldn't work if wired exactly as IVO did it.

My Magnum has a lycoming. I would LOVE to have an IVO IFA prop on it....if I trusted it for the application. I have heard that the IVO is not well suited to direct drive applications due to the shock impulses from the cylinders firing causing problems. Fine for gear and belt drive, but I don't EVER want to be a pilot during a prop failure! If I were to hear of more people using the IVO for direct drive applications, I would consider it.

I had the IVO IFA on my previous Avid, a 582 powered MKIV HH. It was awesome on there.

My friend just broke a jackscrew by trying to turn it. You can't turn it by hand. There are layers of planetary gears in there that don't allow the shaft to be turned by hand. Only by the motor.

Chris

[EDMO 1078]

Well I am very glad to see this discussion since it has come at the most oppourtune time. I played with my Warp Drive prop some more last weekend and flattened it out to 12 degrees. The thrust and climb was significantly better but the cruise sucked; plus I started to push my EGT and CHT limits, but that will require some richer jetting and probably a Hacman for the Bing 64's on my Subaru.

What it did convince me of was the value of having an IFA prop so I bit the big one and ordered an IVO medium 72" IFA. I have not looked at the postings Chris did on the Yahoo Avid site yet but will do that. I am totally unfamiliar with the IVO prop since I have only had Warp Drive props. From what Chris is saying to set the prop up at the best compromise between climb and cruis with the IFA in the middle of the travel sounds very good. What I am not familiar with is how do you do this? This is probably a stupid question but can you adjust the prop like it is a ground adjustable prop independent of the IFA and that setting can then be set at the middle of the IFA adjustment range?

I hope I like this thing; they sure are not cheap!

Randy, If you end up with a 72 inch Warp Drive 3 blade for sale, let me know - I will be needing one for my 81- LSP cant go IFA.

Ed in MO

Edited 27 Mar 2012 by Ed In Missouri

[SuberAvid 617]

Randy

Where do you get a stick grip with so many switch options?

IVO repaired the motor jack screw at no charge and I will re install tommorrow.

The jack screw failure happened without the poly switches installed.

I feel the poly switches will reduce the load on the mechanism.

What amperage of poly switch are you using?

Can you post how you are wiring them with your stick controled switch and relays?

Thanks Herman

Herman,

I have the Ray Allen stick grips with 4 buttons on top and the PTT in the front. The poly switches I installed are teh RHE450's that Chris recommended we start with. I have not connected the prop up yet so have just checked to make sure the circuit was working correctly by tripping he relays and changing the polarity in the brush leads. I thought I had a copy of my wiring diagram at home but will have to get it from the Hangar this weekend and will post it then.

[SuberAvid 617]

Randy, If you end up with a 72 inch Warp Drive 3 blade for sale, let me know - I will be needing one for my 81- LSP cant go IFA.

Ed in MO

Ed,

Not ready to sell the Warp Drive yet. It might just sit around the hangar and collect dust as my emergency backup prop...hopefully never to be needed.

[SuberAvid 617]

Well I finally got the IVO set up completed and did my run/torq sequence and put 3 hours on it today. I must say it makes a pretty impressive change in my plane. First off the stick controls and the poly switch set up with the LED indicator lights at the limits worked perfect. The REH450 polyswitches seem to be just right. As the motor slows down to almost stopped, the poly switch trips, the LED blinks and it resets almost immediately. Thanks Chris for that wiring diagram

The IVO prop is great; I can get about 600 more RPM on takeoff at flat pitch which makes quite an improvement on takeoff. It is hard to say how much because the snow conditions were heavy, soft snow at 40+ degrees so the conditions were so different it is hard to quantify. But the amazing thing is the cruise performance. My plane used to struggle to get just a smidge above 80 mph cruise; now it looks like my cruise is around 93+mph. I spent a lot of time breaking 100 mph today; I sure didn't see that unless I had a strong tail wind before. It's burning around 5 gph at 93+mph cruise at 3800 rpm vs 3.5 to 4 gph at 80mph at 3800 rpm but I can still back off to economy cruise if I want to. It is a pretty amazing difference; I am impressed.

[Av8r3400 1179]

You have the Subaru, but I thought I'd mention this anyway.

A friend running a controllable ivo with a 912 had some issues with high pitch full throttle for high cruise speeds. This caused too much cylinder pressure and caused leaking at the bases and heads. Leaking stopped when he gave himself a minimum rpm at full throttle of 5200. You may want to watch your head gaskets if you do this often.

Just FYI.

[SuberAvid 617]

You have the Subaru, but I thought I'd mention this anyway.

A friend running a controllable ivo with a 912 had some issues with high pitch full throttle for high cruise speeds. This caused too much cylinder pressure and caused leaking at the bases and heads. Leaking stopped when he gave himself a minimum rpm at full throttle of 5200. You may want to watch your head gaskets if you do this often.

Just FYI.

Thanks, I'll watch that. Do you know if there is a way to put a manifold preassure guage on these?

[EDMO 1078]

Well I finally got the IVO set up completed and did my run/torq sequence and put 3 hours on it today. I must say it makes a pretty impressive change in my plane. First off the stick controls and the poly switch set up with the LED indicator lights at the limits worked perfect. The REH450 polyswitches seem to be just right. As the motor slows down to almost stopped, the poly switch trips, the LED blinks and it resets almost immediately. Thanks Chris for that wiring diagram

The IVO prop is great; I can get about 600 more RPM on takeoff at flat pitch which makes quite an improvement on takeoff. It is hard to say how much because the snow conditions were heavy, soft snow at 40+ degrees so the conditions were so different it is hard to quantify. But the amazing thing is the cruise performance. My plane used to struggle to get just a smidge above 80 mph cruise; now it looks like my cruise is around 93+mph. I spent a lot of time breaking 100 mph today; I sure didn't see that unless I had a strong tail wind before. It's burning around 5 gph at 93+mph cruise at 3800 rpm vs 3.5 to 4 gph at 80mph at 3800 rpm but I can still back off to economy cruise if I want to. It is a pretty amazing difference; I am impressed.

Randy, That's OK about not selling the prop - wont need one for a while. Can you give me the drive ratio of your engine, the specs on your WD prop, pitch used, the rpms for static, cruise, etc? I know your Stratus runs faster than my Reductions, but the seller only used mine for 25 hours and was totally in the dark about rpms, etc. First said 4800 static/cruise, then 4200....4400??? Believe my ratio is 1:1.84.

Thanks, Ed in MO

[EDMO 1078]

Thanks, I'll watch that. Do you know if there is a way to put a manifold preassure guage on these?

That should be doable-Just tap into the manifold - maybe an unused fitting - But I don't have the twin manifold on mine.

A lot of my classes in AMT covered the necessity and use of the MAP on engine power management - (now, if I could just figure out how to use water-injection or that JATO boost, then I could GO like the big boys did it!) ;<)

I should have stated "ABSOLUTE NECESSITY" for variable or constant-speed props, was what we were taught.

Ed in MO

Edited 2 Apr 2012 by Ed In Missouri

[herman pahls 9]

Randy It is great to hear your subaru IFA results.

Today was an excellent Kitfox day for me also.

The rains stopped and I had my first flight with the IVO IFA system and with the polyswitches.

Since it was the first flight with the IFA feature I have yet to install the limit washers for high and low pitch which would set off the polyswitches.

Leni said the limit washers damaged the jack screw.

I am looking forward to the polyswitches since I already dislike the IVO breaker since it takes too long to reset when it does go off.

Some members of this forum do not use limit washers but I found that I have no idea what my pitch is set at unless I do a full throttle run up after each landing.

I landed on a 400 foot sand bar this afternoon and had to take some pitch out on take off roll to get ideal take off RPM for the 582.

I did not want to do a full throttle run up on soft sand.

Thanks again ChrisB for helping us out.

It was windy today so I have no idea if any speed gain with the IFA but with IFA prop and HACman I have never seen this low of fuel burn at say 5500 rpm.

The EGT's go down as expected with more pitch and the HACman will bring the EHT's back up.

I need advice so that I do not damage the 582 with too much pitch even with the EGT's and CHT's at or below where they belong.

Thanks Herman Oregon 541 404 6464

Edited 2 Apr 2012 by herman pahls

[akflyer 1427]

Herman,

I just bump the switch to take some pitch out after landing. I will go full power on takeoff and bump the switch if needed to make 6500. The switch for my prop is right next to the throttle so I can hit it with my thumb without taking my hand off the throttle.

If you put limit washers on I would make them nylon. The metal washers destroyed my shaft. I really dont think that the limit washers are really needed with a 582. There is not enough tq in this engine to require very much pitch change at all, just a little bump here and there makes a HUGE difference.

I will set my prop for cruise by leveling off WOT and bump in the pitch to keep the RPM at 6450 -6500.

[ChrisBolkan 130]

That's very cool that the Ivo and polyswitches are working out and thank you for the kind words. FYI, I set the mechanical limits on the IVO so it was a solid climb prop at one end and a cruise prop at the other end. Not really much total change, but made a lot of difference.

One good thing about doing it that way is that I never had to worry about things like oversquaring (overloading) the engine or anything like that. At either end of travel, it wasn't a prop you couldn't run all the time. I just had to watch the EGT's and adjust mixture to keep EGT's where I wanted them.

Chris

[herman pahls 9]

My type A personality requires limits so I installed the limit washers and can see how Leni says the metal washers can damage the lead screw threads. I will look into nylon washers once I figure out the spacing needed.

With the limit washers in place the poly switches are doing their job and I have yet to re-set the Ivo breaker.

I have a hard time getting over how cool a 62 cent product can be.

Chris,I have not yet installed the indicator lights but am curious how they work since they are wired parallel to the poly switches.

Seems like while the pitch switch is activated the lights would always be lit even when the poly switch opens.

Or does the light change in intensity due to current change and that is the indicator?

Also I like your over squared analogy.

When flying a constant speed prop Lycoming the manifold pressure and tach are used to prevent over squaring.

Is preventing over squaring with a 582 a total seat of the pants feeling or is there an analytical way to guage that.

Thanks Herman

Edited 4 Apr 2012 by herman pahls

[herman pahls 9]

Chris or Randy

I flew for the first time with limit washers and the poly switches this afternoon and the results were great.

I tried 2 different types of incandescent bulbs from radio shack and wired them in parallel with the poly switched as the ChrisB diagram shows with no results at all as indicator lights as

the lights never lit up let alone blinked when the poly switch felt the strain of the limit switches.

I tested the lights with 12 volts and they lit up so I know they work.

I then hooked up one side of a light to 12 volts and the other side to a polyswitch and the light would dim momentarily when the poly switches sensed the limit washers.

I would appreciate help with my errors or misunderstanding of how to do the indicator lights.

Thanks Herman

[akflyerbob 41]

Getting ready to assemble an IFA

where do I find ChrisB's diagram???

[ChrisBolkan 130]

Chris or Randy

I flew for the first time with limit washers and the poly switches this afternoon and the results were great.

I tried 2 different types of incandescent bulbs from radio shack and wired them in parallel with the poly switched as the ChrisB diagram shows with no results at all as indicator lights as

the lights never lit up let alone blinked when the poly switch felt the strain of the limit switches.

I tested the lights with 12 volts and they lit up so I know they work.

I then hooked up one side of a light to 12 volts and the other side to a polyswitch and the light would dim momentarily when the poly switches sensed the limit washers.

I would appreciate help with my errors or misunderstanding of how to do the indicator lights.

Thanks Herman

Hi herman,

I haven't looked at the circuit for a while, but the idea is that the polyswitch is a short circuit until the current of the stalled motor opens it up. Since the incandescent or LED light is in parallel with the polyswitch, it will not light because all of the current is being bypassed through the polyswitch. Whan the polyswitch does open due to the stopped motor, as long as you hold the switch on, the light will light because now current cannot flow through the polyswitch, to it goes through the light and lights it. However, the current flow through the light is not enough to turn the motor. Once you release the switch, or reverse the direction of the motor, the light extinguishes. If you are using LED's and they don't light you might have the polarity reversed. It doesn't matter how you wire an incandescent light.

Regarding the washers and limits, there should be rubber like washers that compress at the at each limit in addition to whatever spacer washers ar in there. These rubber washers are essential to proper operation and to prevent damage. As the adjustment nut rides up and down the jackshaft, when it reaches a limit at one end or the other, you don't want an abrupt metal on metal stop. The rubber (or compressable plastic) washer absorbs the shock at the end of travel and allows the current flow to ramp up more slowly so the polyswitches (or original breaker) can do their thing before damage occurrs.

Hope this makes sense.

Chris

[SuberAvid 617]

Randy, That's OK about not selling the prop - wont need one for a while. Can you give me the drive ratio of your engine, the specs on your WD prop, pitch used, the rpms for static, cruise, etc? I know your Stratus runs faster than my Reductions, but the seller only used mine for 25 hours and was totally in the dark about rpms, etc. First said 4800 static/cruise, then 4200....4400??? Believe my ratio is 1:1.84.

Thanks, Ed in MO

Hi Ed,

With the Warp Drive I was running the 72" 3 blade square tip with the HP hub. My Stratus redrive is 2.2:1 so you will have to do some conversion to see what you would have for prop speed at your rpm or RPM at the same prop speed. I found that for me the best pitch setting was 14 degrees at the tip. I set mine with the blade horizontal and lined it up with my horizontal stabilizer; the degrees is the difference between the prop hub face and the tip. At 14 degrees my takeoff RPM was 4250 and climb was around 700 fpm solo. At 14 degrees the cruise that I typically used was 3850 RPM and that was about 80 mph and it burned about 4 gph. If I backed off to 3600 rpm it was about 70 mph and burned around 3 gph. It would fly just fine at 3400 rpm and burned around 2.5 gph. When I ran the cruise RPM up to 4000 it would burn around 5 gph but it didn't seem to get much additional speed; it would only get to around 82-83 mph. That is why I am so amazed that the IVO gives me 93 mph when I crank the pitch in at 3800 rpm. I know the blade shape on the IVO is much different than the Warp Drive and the IVO is much more flexible than the Warp Drive; it is very soft in comparison so I am sure it is not nearly as strong as the Warp Drive.

With the 1.84:1 redrive I think you will probably need to pitch your prop closer to 11 or 12 degrees to get your RPM where you need it to be. 3800 RPM is about the max torque for the EA81 and that seems to be where it is happiest in cruise. It is a whole lot different than the 582 in cruise which as others have said on here, changes rpm constantly with the changes in wind ; headwind/tailwind/turbulence, etc. The Subaru just purrs along at the same rpm no matter what you are getting hit with in the air.

[SuberAvid 617]

That should be doable-Just tap into the manifold - maybe an unused fitting - But I don't have the twin manifold on mine.

A lot of my classes in AMT covered the necessity and use of the MAP on engine power management - (now, if I could just figure out how to use water-injection or that JATO boost, then I could GO like the big boys did it!) ;<)

I should have stated "ABSOLUTE NECESSITY" for variable or constant-speed props, was what we were taught.

Ed in MO

Ed,

I assume that that tap in to the manifold is in the intake manifold behind the carbs? I have a balancing tube between the intake manifolds on my motor; can I put a tee in it for the line to run to the manifold pressure gage? I used to have a vacume gage on a couple of my past rigs and if I remember correctly the line was run from a port somwhere at the base of the carbs. It seems like this would be measuring the same thing so is the manifold pressure gage measuring absolute presure instead of gage pressure which would be a negative (vacume)?

Also, what would be the "correct" pressure for the Subaru in cruise at 3800 rpm?

I looked up a manifold gage on the MGL web site and they are $270 so not too bad. I have all MGL gages in mine and I really like them.

[SuberAvid 617]

Getting ready to assemble an IFA

where do I find ChrisB's diagram???

Hi Bob,

Hope you found it; if not it is on the first page of this post that Chris says the diagram is a post he did on the Yahoo Avid web site. I managed to find it after browsing around on there a bit. I wish I could get my scanner to work with this new computer and I would post the modified diagram using two automotive 5 pin relays to replace the manual IVO switch so it is controled by the micro-switches on the stick. The relays just take the full motor amperage when you to trigger them with the stick switches, and one for each polarity direction to the motor; otherwise the wiring diagram is the same and the LED lights are wired parallel to the polyswitches as per the diagram.

[EDMO 1078]

Ed,

I assume that that tap in to the manifold is in the intake manifold behind the carbs? I have a balancing tube between the intake manifolds on my motor; can I put a tee in it for the line to run to the manifold pressure gage? I used to have a vacume gage on a couple of my past rigs and if I remember correctly the line was run from a port somwhere at the base of the carbs. It seems like this would be measuring the same thing so is the manifold pressure gage measuring absolute presure instead of gage pressure which would be a negative (vacume)?

Also, what would be the "correct" pressure for the Subaru in cruise at 3800 rpm?

I looked up a manifold gage on the MGL web site and they are $270 so not too bad. I have all MGL gages in mine and I really like them.

Randy, Thanks for all the WD info - I am going to print it for future reference.

As for the MAP gage, I think you should ask Stratus what they recommend.

The MAP gage will read atmospheric pressure when the engine is not running - you can check it with the local Pressure.

Anytime the engine is running, the MAP will be less than atmospheric pressure - unless you have a turbo, and there you can get into more trouble. Will have to get my school books out to tell you more than that. I,m sure there are some pilots who know more than I do about MAP.

I have 2 or 3 MAP gages, different sizes, that I would sell cheap - not familiar with your choice of gages, but will check Spruce.

Got to hide eggs tomorrow. Happy Easter.

Ed in MO

Edited 8 Apr 2012 by Ed In Missouri

[EDMO 1078]

Hi Ed,

With the Warp Drive I was running the 72" 3 blade square tip with the HP hub. My Stratus redrive is 2.2:1 so you will have to do some conversion to see what you would have for prop speed at your rpm or RPM at the same prop speed. I found that for me the best pitch setting was 14 degrees at the tip. I set mine with the blade horizontal and lined it up with my horizontal stabilizer; the degrees is the difference between the prop hub face and the tip. At 14 degrees my takeoff RPM was 4250 and climb was around 700 fpm solo. At 14 degrees the cruise that I typically used was 3850 RPM and that was about 80 mph and it burned about 4 gph. If I backed off to 3600 rpm it was about 70 mph and burned around 3 gph. It would fly just fine at 3400 rpm and burned around 2.5 gph. When I ran the cruise RPM up to 4000 it would burn around 5 gph but it didn't seem to get much additional speed; it would only get to around 82-83 mph. That is why I am so amazed that the IVO gives me 93 mph when I crank the pitch in at 3800 rpm. I know the blade shape on the IVO is much different than the Warp Drive and the IVO is much more flexible than the Warp Drive; it is very soft in comparison so I am sure it is not nearly as strong as the Warp Drive.

With the 1.84:1 redrive I think you will probably need to pitch your prop closer to 11 or 12 degrees to get your RPM where you need it to be. 3800 RPM is about the max torque for the EA81 and that seems to be where it is happiest in cruise. It is a whole lot different than the 582 in cruise which as others have said on here, changes rpm constantly with the changes in wind ; headwind/tailwind/turbulence, etc. The Subaru just purrs along at the same rpm no matter what you are getting hit with in the air.

Randy,

Not saying you are "wrong" on your figures, but "WOW, those are totally LOW compared to what I have read about the Stratus.

I know that the cam regrind raised the torque, but the figures I have read are more like 4800 static/cruise and 5600 unload.

Maybe you need to contact Stratus, as I think you are running this engine under-powered with the WD.

Of course, I am like the blind man describing the elephant in this case.

Are you running the Soob computer? Mine is old tech, timing set at 28 BDC, two-brl Holley carb, point distributer.

Maybe check your timing, dwell?

I dont have the HP as yours is advertised. Yours is supposed to be 115. Mine is somewhere between 80 and 100, and the heads have been milled .040, but dont know if the cam has been reground.

Owner said to set my WD at 10 degrees - guess that is with the protractor from WD. However, I did not get the prop with the engine.

Mine was supposedly run at 5400 and a prior owner "blew the crank". A new or regrind crank was installed and the heads milled.

The seller said, "Don't even go there!" And, I don't plan on pushing it that much, He sold it because it was too heavy for his Pelican and two people on floats. He bought a 912, 100hp to replace it.

Anyhow, just had concerns about your figures not being the same as I have read about the Stratus. Hope you check on this.

Many thanks for the WD info.

Good Flying, ED in MO

P.S. I just went to Stratus 2000, and they are saying 100hp @ 5400??? (Of course, if you want it to last, then run slower, IMO.)

Edited 11 Apr 2012 by Ed In Missouri

[EDMO 1078]

Chris or Randy

I flew for the first time with limit washers and the poly switches this afternoon and the results were great.

I tried 2 different types of incandescent bulbs from radio shack and wired them in parallel with the poly switched as the ChrisB diagram shows with no results at all as indicator lights as

the lights never lit up let alone blinked when the poly switch felt the strain of the limit switches.

I tested the lights with 12 volts and they lit up so I know they work.

I then hooked up one side of a light to 12 volts and the other side to a polyswitch and the light would dim momentarily when the poly switches sensed the limit washers.

I would appreciate help with my errors or misunderstanding of how to do the indicator lights.

Thanks Herman

A note from a dum ole machinist who knows nothing about etronics: sometimes a 470 ohm resister is used in front of a LED.

Dont know what this means - but 2 cents worth.

ED in MO

[EDMO 1078]

Ed,

I assume that that tap in to the manifold is in the intake manifold behind the carbs? I have a balancing tube between the intake manifolds on my motor; can I put a tee in it for the line to run to the manifold pressure gage? I used to have a vacume gage on a couple of my past rigs and if I remember correctly the line was run from a port somwhere at the base of the carbs. It seems like this would be measuring the same thing so is the manifold pressure gage measuring absolute presure instead of gage pressure which would be a negative (vacume)?

Also, what would be the "correct" pressure for the Subaru in cruise at 3800 rpm?

I looked up a manifold gage on the MGL web site and they are $270 so not too bad. I have all MGL gages in mine and I really like them.

Randy, I have to get my fuselage to the welder this week for mods. Will look in my schoolbooks and see what is written on the MAP and hopefully copy it and post it if usefull - Have my doubts tho, because they only concern the old long-stroke engines, running like 24 Map / 2400 rpm, etc. Dont know how that converts to our modern short-stroke efficient engines.

Ed in MO

[SuberAvid 617]

Randy,

Not saying you are "wrong" on your figures, but "WOW, those are totally LOW compared to what I have read about the Stratus.

I know that the cam regrind raised the torque, but the figures I have read are more like 4800 static/cruise and 5600 unload.

Maybe you need to contact Stratus, as I think you are running this engine under-powered with the WD.

Of course, I am like the blind man describing the elephant in this case.

Are you running the Soob computer? Mine is old tech, timing set at 28 BDC, two-brl Holley carb, point distributer.

Maybe check your timing, dwell?

I dont have the HP as yours is advertised. Yours is supposed to be 115. Mine is somewhere between 80 and 100, and the heads have been milled .040, but dont know if the cam has been reground.

Owner said to set my WD at 10 degrees - guess that is with the protractor from WD. However, I did not get the prop with the engine.

Mine was supposedly run at 5400 and a prior owner "blew the crank". A new or regrind crank was installed and the heads milled.

The seller said, "Don't even go there!" And, I don't plan on pushing it that much, He sold it because it was too heavy for his Pelican and two people on floats. He bought a 912, 100hp to replace it.

Anyhow, just had concerns about your figures not being the same as I have read about the Stratus. Hope you check on this.

Many thanks for the WD info.

Good Flying, ED in MO

P.S. I just went to Stratus 2000, and they are saying 100hp @ 5400??? (Of course, if you want it to last, then run slower, IMO.)

Hi Ed,

As you saw, the Stratus is 100 HP and they get that after reconfiguring the cam and planing the heads .040 which raises the compression to just over 9:1 so you can still burn 87 octain mogas in them. The published redline is 52 - 5400 rpm. Timing is set at 12deg BTDC at 1000 rpm and max of 32 deg BTDC at 3500 rpm. Mine has dual electronic ignition pickups in the distributor which is from RAM and not stratus. The carbs are dual Bing 64's, altitude compensating, just like the ones they run on the Rotax 912's but jetted differently. All I can tell you are the numbers I have found from my experience flying it. I know my performance numbers are somehat lower than are published and I have talked to Mykal at Stratus about it and am still trying to figure out why. Still, I think you will find that cruise RPM of 3800 to 4000 is about right. I am pretty happy with the motor and the performance across the spectrum. It will be interesting to hear what you end up with for performance numbers. Hurry up and get that thing in the air!