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  #11  
Old 08-04-2017, 09:56 AM
AviatorJ AviatorJ is offline
 
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Quote:
Originally Posted by mdmba View Post
never to embarrassed to ask for questions from the Vans Community.
Anytime you ask a question on a public forum be prepared for a slew of answers and advice... On constant speed planes I take over full everything and trim back to 2500 and MP no higher than 25 500' up. For cruise I bring it to 2300 and MP to 21 or so... adjust periodically as needed.

Now I've been flown with other pilots that do it different....
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  #12  
Old 08-04-2017, 10:02 AM
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DanH DanH is offline
 
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Originally Posted by mturnerb View Post
A tremendous help in understanding engine management would be to take the APS engine management course out of ADA, Oklahoma. They have an online version as well as a live course. I did both soon after buying a Bonanza - it also has a 6 cylinder fuel injected engine (Continental, but principles are all the same).
Not all. General engine management principles are universal, need to be learned, and APS is a good place. However, specific operational details (exactly which knob to diddle and when) can vary a lot. Continental constant flow injection is nothing like the Bendix-style typical on a Lycoming, and neither shares anything with the SDS-based pulse width systems.

As for the scary red box, an RV-10 pilot with a normally aspirated 540 might be better off consulting the Lycoming engine chart. See "Limiting Manifold Pressure For Continuous Operation" on the left chart. It assumes best power mixture, so there is no need to run silly rich; any setting to the left of the line is safe at ~150 ROP. If it won't cool (assuming mixture balance), you have an airframe problem.
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  #13  
Old 08-04-2017, 10:47 AM
Sig600 Sig600 is offline
 
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Originally Posted by DanH View Post
Not all. General engine management principles are universal, need to be learned, and APS is a good place. However, specific operational details (exactly which knob to diddle and when) can vary a lot. Continental constant flow injection is nothing like the Bendix-style typical on a Lycoming, and neither shares anything with the SDS-based pulse width systems.

As for the scary red box, an RV-10 pilot with a normally aspirated 540 might be better off consulting the Lycoming engine chart. See "Limiting Manifold Pressure For Continuous Operation" on the left chart. It assumes best power mixture, so there is no need to run silly rich; any setting to the left of the line is safe at ~150 ROP. If it won't cool (assuming mixture balance), you have an airframe problem.

I think his point was for the OP to get formal training, we're getting into the weeds here.

To the OP...

This:

Quote:
Originally Posted by hydroguy2 View Post
Best way to answer your questions would be 5-10hrs of transition training with Mike Seager or similar RV CFI
Then go to the APS school. Internet formus are a great place for discussion, but there is a lot of bad information too. Start with those two rounds of formal instruction, then go from there.

I recommend searching Pelicans Perch on Avweb too... he's written a lot of good articles on engine management, as has Mike Busch.
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  #14  
Old 08-04-2017, 05:07 PM
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RV8JD RV8JD is offline
 
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mdmba: I'm not sure where in Washington State you are, but you might want to fly with Terry Burch. He can help you with your questions and fly with you. He is located at Arlington Airport (KAWO).

If you are interested, PM me and I will send you his contact info.
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  #15  
Old 08-04-2017, 05:12 PM
mdmba mdmba is offline
 
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I had a great chat w EFII owner..and he answered all of my questions.

Thanks again for all the input...

Im at Auburn WA(S50)
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  #16  
Old 08-04-2017, 07:50 PM
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DanH DanH is offline
 
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Quote:
Originally Posted by Sig600 View Post
Then go to the APS school. Internet formus are a great place for discussion, but there is a lot of bad information too. Start with those two rounds of formal instruction, then go from there.
I recommend searching Pelicans Perch on Avweb too... he's written a lot of good articles on engine management, as has Mike Busch.
Perhaps a bit off topic, but I find the above amusing, in a perverse sort of way.

Forums have a bad rep, no question. The place is full of sock puppets with no signatures, advertisers with claims, and folks who are just honestly ignorant, in the dictionary sense of the word. However, the internet also provides a link to accurate information, in great depth and detail, often at no cost.

Then we have magazines, and information for sale. Although we tend to believe what we read and buy, some of it is no better than the forum average.

So who should you believe? Nobody. Ask for supporting data, or dig it out yourself. Trust but verify.

Allow an example. In a previous post, I brought up the "scary red box". Let's look at an iteration of the box, the "red fin", from a Mike Busch article, Sport Aviation, December 2012. Note the dire caption. Woe to those who operate in the "abusive purple zone"!



Look hard at the numbers. The chart doesn't begin until 85% power. The bible according to Busch says that at 85%, anything leaner than 225F ROP is in a caution zone, and 175F ROP is abusive.

Now look at raw data from a public document anyone can download. It's from the FAA dyno at Hughes, running an IO-540K, accepted as a detonation-sensitive example of the Lycoming NA sixes. The data was taken with 245F oil, 100F+ inlet air, and the test cylinder at 475F CHT...conditions much more severe than any reasonable pilot would allow in the field.



How odd. Even at 2700 and WOT (28"+), it turns out best power is around 125 ROP, deep in Busch's "abusive zone". Running at 225 ROP, as advised, simply means reduced power.

Let's get oversquare for the fixed pitch pilots, 2350 and 28"...hard against the Lycoming charted "Maximum Manifold Pressure" line.



Gosh. Again we see that even under the most severe pro-detonation conditions, 125 ROP is perfectly fine, and richer is just an expensive power reduction.

Still think the internet is always bad, and famous writers are always good?
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Last edited by DanH : 08-05-2017 at 07:21 AM.
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  #17  
Old 08-04-2017, 08:19 PM
Sig600 Sig600 is offline
 
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Well as long as we're going off topic...

Busch isn't talking about immediate damage in that diagram, he's referring to long term health of the cylinders. His "danger zone" is where long term damage is occurring, not necessarily imminent doom and destruction. I've never heard him say or write that there is immediate danger in the red zone, just that time spent there is time off the back end of the engine. APS teaches the same, backed up with data. EGT/ICP/CHT all correlate, CHT being the biggest determining factor in long life.

I flew for a 135 operator with turbo charged IO-550's that can validate his operating principles (we never cruised richer than -50). Multiple engines made it to TBO with no issue, only to be torn down and reported as still looking new inside. Sadly, one led to the loss of an airplane as its factory new replacement catostrophically failed at 180 hours (connecting rod failed, went through crankcase).
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Last edited by Sig600 : 08-04-2017 at 08:24 PM.
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  #18  
Old 08-04-2017, 11:24 PM
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Quote:
Originally Posted by Sig600 View Post
Busch isn't talking about immediate damage in that diagram, he's referring to long term health of the cylinders. His "danger zone" is where long term damage is occurring, not necessarily imminent doom and destruction.
Trust by verify. Look at the numbers. At 2700 and full throttle, the horsepower difference between 125 ROP and 225 ROP is 291 vs 285. That's a 2% power reduction in return for a fuel consumption penalty of 14%. Now consider if 2% can make a significant difference in the long term health of a cylinder. Remember, this issue has nothing to do with cruise. The scary red box deals with climb power...overall, a short term use.

Quote:
I've never heard him say or write that there is immediate danger in the red zone, just that time spent there is time off the back end of the engine. APS teaches the same, backed up with data.
Long term wear data for red box observance in climb? In God we trust. All others are asked to bring supporting documents.

Again, this has nothing to do with LOP cruise.

Quote:
EGT/ICP/CHT all correlate, CHT being the biggest determining factor in long life.
Make of list of all the ways CHT can be reduced, then consider....why would anyone choose fuel? The answer is because all the more sensible choices are locked by certification.

We have experimental freedom, but often waste it on self-flagellation. You want to hear a definition of insane? It's a guy worrying about the red box, while step climbing a high performance airplane at reduced power and some ridiculous fuel burn to keep CHT down, behind a 540 with bumped compression, cold air induction, and an EI with advanced timing.
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Last edited by DanH : 08-04-2017 at 11:26 PM.
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  #19  
Old 08-05-2017, 06:41 AM
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Weasel Weasel is offline
 
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Quote:
Originally Posted by DanH View Post

Long term wear data for red box observance in climb? In God we trust. All others are asked to bring supporting documents.

Again, this has nothing to do with LOP cruise.

I like the analogy!!!

A piece of data I have been in search of is documentation of Cyl failures vs. CHT.

anyone help me out?

Various sources have been spitting numbers around but no data showing the failures. Just because some source says the metal in the head becomes 1/2 strength at 400 deg. F. does not mean it has not been designed to handle continuous operation at some higher temperature. I am not in disagreement with running cooler....I only want data supporting the correlation. I hope this is not too far off topic from the OP
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Last edited by Weasel : 08-05-2017 at 03:41 PM.
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  #20  
Old 08-05-2017, 10:46 AM
esco esco is offline
 
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Default Flight Test Data helps

To the OP:

Did the original builder/ owner provide their flight test data or POH?

If either exists, you might find answers to some of your questions. A close read will be required; a POH might be lifted text from another (unverified) source, and gundecked test data could misleading as well.

If either document does not exist, my "glass half full" perspective is that you have a wonderful opportunity to learn your airplane in detail.
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