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About to order a Pmag

Brantel

Brantel

Well Known Member
I am about to take the plunge and order a Pmag to replace my impulse coupled mag. I will leave the other mag as is for a while till I can save some more coins.

I can't find any info on what spark technology is used in the Pmag. CDI or ?? In other words, how long is the spark duration?

I will need a new non impulse drive gear. Anyone got a good source?

Plan to go with auto plugs. Any comments on using their pre-made harness over the cut your own harness?

I chose Pmags due to the easy install and cool technology. The competition can't compete with the easy install aspect. I think the growing pains are just about over with the Pmags and I am willing to give it a shot.

My goal is easier starting under all conditions and smoother operation at all power settings. If I can run leaner then that is a bonus but that is not my primary goal.
 
Hey Brantel,

I got my drive gear from ECI. I know that P-mag sells one also. I would make your own harness from their kit. That way you can get the leads the perfect length. They are not too difficult to fabricate. The trick will be to use some silicone grease to slide the boots on with.

I really couldn't be happier with my P-mags. Easy starting, smooth running and great economy.

There is one thing I would do differently. When you connect the electrical connections, they use a simple "set" screw that you tighten down onto the wire ends. I find this to be a low quality connection. I am going to find some spade type connectors that I can crimp onto the wiring then the set screw will be a bit more effective. You could use a standard Dynon pin connector then dimple it so the set screw rides in the dimple. (this may be confusing, but you'll see what I am talking about when you wire it up.)

Talk to Repucci about the spark duration. He's got lots of info on that.
 
One more happy Pmager

I have been running one Pmag on my -4 and if I remember to turn all the switches on it starts up real good :D. Idles much smoother than with two mags. Fully agree with what else has been said. I have some ends to put on the wires to make that better connection Tony is talking about, will do this at the next annual. I have a second Pmag and will probably install that one too during the annual.
 
Brian,

I bought a Ferrule crimp tool off of Ebay to secure the wires into my EMAG. While I don't have a lot of hours on my RV, I trust this is the best way to wire an Emag/PMag.

IMG_0001.JPG
 
A happy E- and P-mag owner here! While I have never had a problem with the connections, I agree that they could be better. You can figure any of a number of ways to improve, even if it is solving a non-problem. I have one set of pre-made and one set of self-made plug harnesses, and I think it is better to do it yourself. Just follow the instructions. As I recall, they are about the same price, but you get a neat new tool when you go the DIY route.

You will love the P-Mag. Let us know how it works out.

Bob
 
While I agree the set screws are on the face of it an 'ugly' way of doing it they in fact appear to work well. The wires take on a set and dont want to come out and I have had no loose screws.

My advice would be to make your own harness.

I am extremely pleased with my p-mags. They are painless so far. Around 100hrs.

My gears came from AeroSport Power with the engine. I think E-mag sell good ones now after some early problems.
 
P-Mag Success

I bit the bullet and bought a used P-mag from a guy that could not get it to work. Carefully installed and wired it fired up the first time and runs great. Have a low compression engine so a change to the B curve was necessary to make it really smooth. Am glad for the improvement.

Question: is it such a good idea to replace the impulse mag with this? Does it not require some RPMs to generate enought power to fire and so, start with a dead battery? I saw a fellow at Arlington that was out of luck when his battery died since he could not hand prop it. With the impulse still installed he would have gotten going a lot sooner..... just a thought. Bill should be able to advise you accurately.
 
apkp777 said:
...Talk to Repucci about the spark duration. He's got lots of info on that.
Click to expand...
I'm waiting to hear back from Brad and Tom as to the exact coil technology they are using. TX is getting a dusting of snow today, so they closed early.

Flyingguido said:
...Question: is it such a good idea to replace the impulse mag with this? Does it not require some RPMs to generate enought power to fire and so, start with a dead battery? I saw a fellow at Arlington that was out of luck when his battery died since he could not hand prop it. With the impulse still installed he would have gotten going a lot sooner..... just a thought. Bill should be able to advise you accurately.
Click to expand...
I recommended Brian replaced the impulse mag with the P-mag because of the shower of sparks (Five shots on each cylinder "slightly after" TDC below 200 RPM) technology, the hotter and larger spark, etc. Truth is, it really wouldn't matter and he can still start his engine on both the mag and the P-mag. However:
P-mag manual said:
Note 2: Non-starting magnetos require a mechanism to prevent them from firing during start-up. Keyed ignition switches have a jumper on the back that serves this purpose. When installing an E-MAG in place of a non-starting magneto that was controlled by such a switch, make sure you remove this jumper. You do NOT want a start-up block on any circuit controlling your EMAG(s).
Click to expand...

As for being out of luck due to leaving the master on; first don't do that, second, you can power one of your P-mags with a 9 volt battery and hand prop it. It will start much easier than the mag. (A friend did this while on a trip out West.)

Looks like I need to dig out the drawing I did of that setup using a 9 volt battery and post it.

Would it surprise any of you, if I spoke highly of the P-mags?
 
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Just solder the end of the wire and put it in the pmag. I have about 300hrs on mine. That's on the left side, the right has the plasma 3. I love my setup and currently have 440hrs on the plane. that's with the first flight on memorial day 09. I'm running a low compression IO360. I have no wire for the advance and the plasma 3 set for 25degrees timing, which is out of the box timing set at 0 top dead center. I had all my wires made for me with no issues, the lengths seem to be right on.
 
Flyingguido said:
I bit the bullet and bought a used P-mag from a guy that could not get it to work. Carefully installed and wired it fired up the first time and runs great. Have a low compression engine so a change to the B curve was necessary to make it really smooth. Am glad for the improvement.

Question: is it such a good idea to replace the impulse mag with this? Does it not require some RPMs to generate enought power to fire and so, start with a dead battery? I saw a fellow at Arlington that was out of luck when his battery died since he could not hand prop it. With the impulse still installed he would have gotten going a lot sooner..... just a thought. Bill should be able to advise you accurately.
Click to expand...
I agree and I left the impulse mag on the left and installed the Pmag on the right. After you remove the jumper on the ignition switch you start with both mags functioning normally and in case of a dead battery you can hand start it off the impulse mag. Since it is just as easy to install either one, I believe the right is where you want to put the Pmag.
 
Brantel said:
...I think the growing pains are just about over with the Pmags and I am willing to give it a shot...
Click to expand...

Just met with a buddy who was one of the early adopters (Beta tester) and lives right down the road from E-magair. He just spoke with Brad because he's looking for a source for the earlier 113 series. Brad related that he only has one unit left - a "loaner" used when someone has an AOG situation. He went on to say that this "loaner" has not been out the door in nearly a year. I think that goes a long way to say that the growing pains are essentially over. I've run one for about 250 hours now without a single hint of a problem. I just got comfortable enough to add the second unit, and I'm looking forward to trouble free use with this one as well. It sure runs better.

Brantel said:
...My goal is easier starting under all conditions and smoother operation at all power settings. If I can run leaner then that is a bonus but that is not my primary goal...
Click to expand...

You will be able to run a lot leaner - a feature you will grow to appreciate with every fill up.
 
Go for it Brian.

I have a whooping 14.3hrs on my Emag/Pmag combo, but so far so good. I tried to blame them for a problem last week, but turns out I'm just a moron.
 
oh, I forgot, the worse part about doing the changover from the mag is the studs in the block. I tried double nuting it and no worky. I ended up using one of those things you use for stripped over bolt heads, you can get them at sears, the size I used was a 5/16, it fit right over the stud and it was a tight one to get out, but it finally came out. make sure and get I think a 2amp circuit braker for the system for in the panel.
 
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I replaced my non impulse mag last week with a pmag & couldn't be happier. It resolved my starting problem along with a couple of other problems.
 
You guys may have convinced me that I might want to swap the non-impulse mag...I guess as long as I turn the Pmag on for start it does not matter what side it is on.

I see two advantages to this:

1. Easy to hand prop if I need to..
2. I can reuse the gear from the non-impulse mag and save some coins for now...

Are there any issues with clearance on that side with the battery box in the recommended stock location?

Something tells me that I will be adding the second Pmag sooner rather than later!!!
 
I dumped the impulse mag first. I don't like the impulse coupling because it CAN come apart and will often trash the accessory geartrain. Minimal chance if all the AD's are complied with, but still... Also saves a little weight. Six of one, half dozen of the other...
 
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Adjust the terminals for easy access

I have a couple of friend who are using the PMags, both are happy with them. The only issues we had was high cylinder head temperatures. That is easily rectified by adjusting the advance with the software. One guy has two of them in his unlimited aerobatic aircraft and after adjusting the advance his temps went down to normal during unlimited sequences. When installing make sure the connectors are easily accessible in the event that you want to hook up a laptop to change settings.
 
Who's your buddy

Toobuilder said:
Just met with a buddy who was one of the early adopters (Beta tester) and lives right down the road from E-magair. He just spoke with Brad because he's looking for a source for the earlier 113 series. Brad related that he only has one unit left - a "loaner" used when someone has an AOG situation. He went on to say that this "loaner" has not been out the door in nearly a year.
Click to expand...

Who is your buddy? I live about 9 miles from EMag and know Brad and Tom well. If fact I was probably the last guy to use that loaner. I'm very happy with dual PMags.
 
Blue Lion said:
I have a couple of friend who are using the PMags, both are happy with them. The only issues we had was high cylinder head temperatures. That is easily rectified by adjusting the advance with the software. One guy has two of them in his unlimited aerobatic aircraft and after adjusting the advance his temps went down to normal during unlimited sequences. When installing make sure the connectors are easily accessible in the event that you want to hook up a laptop to change settings.
Click to expand...

Better yet, run the wires into the cockpit and install an EICommander.
 
If you replace the impulse mag with a P-Mag, please don't do what I did.....

Fitted both P-Mags, started 3rd blade, wouldn't run on one mag.

Checked wiring.

Checked timing.

About to call Brad when I spotted it - DOH !

I forgot that there is a spacer ring to accommodate the extra length of the impulse mechanism.

The P-Mag hadn't engaged it's gear in the drive.

Off came the spacer, on went the P-Mag - Voila :rolleyes:

Told Brad - he added it to the dufus section.

Very happy with ours after 10 hours on a TMX IO-360. Easy set up and timing, starts very well, idles well - just started an 8 and will be dual P-Mags on that one as well.
 
P-Mag on the way. Spruce had em in stock. Emagair direct was out of stock, next batch a week or two away. I have decided to put it on the right side to save the cost of the gear among the other advantages...

Hope to install it this weekend!!!


Now what are the suggestions??? Run in Mag mode, A curve, B curve or modified B curve and if the later, what do I modify? I have a carbed O-360 with 8.5:1 pistons and a FP prop....
 
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Brantel #1

To answer the question posed by Brantel in the original posting, which no-one has responded to. As far as I know, the E-PMag, G3I, Electroair, and Electromotive are all inductive systems, that is, they pass a current through the coil(s) which, through dI/dT, generate the coil's secondary high voltage. This type of ignition is somewhat more subject to misfiring with oil or carbon fouled sparkers because of their lower rate-of-rise of voltage. But if the system makes use of an MSD box, then it is capacitive discharge.

The spark endurance is a function of the peak current and the coil primary inductance, and each maker would have to respond to that.

With a happily operating engine, whether CDI or inductive shouldn't make much difference, as efficient operation would depend more on the research that has gone into the mapping of the spark advance based on MAP and RPM.

There are some that swear FOR each of them and some that swear AT each of them! ;)
 
Brantel said:
...
I can't find any info on what spark technology is used in the Pmag. CDI or ?? In other words, how long is the spark duration?
Click to expand...
They use a coil, not CDI. However, unlike some of the CDI ignitions out there, they recompute the dwell on every revolution, so the spark duration and intensity is not a factor, especially with our slow turning engines. As E-mag Brad said, "How many matches do you need to throuw on a fire?"

Brantel said:
I will need a new non impulse drive gear. Anyone got a good source?
Click to expand...
Call either Mahlon at Mattituck or Jesse at A.E.R.O. and order and ECi gear or whatever they have in stock.

Brantel said:
Plan to go with auto plugs. Any comments on using their pre-made harness over the cut your own harness?
Click to expand...
Like some of the others have said, you can make your own harness for about the same price and get another cool crimping tool.

Brantel said:
...My goal is easier starting under all conditions and smoother operation at all power settings. If I can run leaner then that is a bonus but that is not my primary goal.
Click to expand...
You will like the P-mag. I give you one year before you replace your remaining mag with a second P-mag.
 
So what all does a person need to switch over both sides? Is it two of the same unit, the gears, the harness, and some new wiring? What plugs do you guys run? Do you use the adapters for the plugs?
 
lancef53 said:
So what all does a person need to switch over both sides? Is it two of the same unit, the gears, the harness, and some new wiring? What plugs do you guys run? Do you use the adapters for the plugs?
Click to expand...

OK, here's the simple answers:
Two P-mags
Two gears
Two harnesses
Wiring to the cockpit (You will want to put each on their own circuit breaker and independent grounds, per the manual.)
- Serial connection wiring is optional but I highly recommend you bring them into the cockpit and install DB9 connectors so you can attach a PC later on.)
Plugs that are reported (BY OTHERS) to work in most installations.
NGK BR8ES 2.5mm Center Electrode (#3961 has solid terminal post)
or
NGK BR8EIX Iridium Electrode
- Gap: 0.030” to 0.035”.
Yes, adapters are required unless you run tractor plugs or you have ECI cylinders set up to take auto plugs.
(A search on "auto plugs" will bring up a LOT of info.)

As a side note, I use the cheap BR8ES plugs and simply replace them every condition inspection. Total cost for eight of these plugs is less than the cost of one aviation plug, about $17.
 
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"major" change requiring Phase I?

Hope to install it this weekend!!!
Click to expand...

Brantel,
Have you checked with your FSDO on whether this is considered a "major" change that requires a 5 hr Phase I test period?
There are other threads you can do a search on and I only mention it as you might want to check with local FSDO and document their interpretation just to stay legal and avoid insurance disputes should anything happen down the road (we all hope not - and I don't say this to imply anything about your iginition choice!). Like some other issues, it appears FSDO opinions can vary from threads I've read in the past. If you have the latest Op Lims, and I expect you do, it's not a big deal to do the Phase I if required and you shouldn't need the FSDO or DAR to go to Phase I and back to Phase II - check your Op Lims for major change paragraph.

I asked my local FSDO about this when I went from dual P-Mag setup I had from first flight through Phase II and answer I got was they considered going to Slick mag setup to be a minor change since it's a certified ignition system but that they considered going the other way around from conventional mag to experimental electronic ignition to be a major change requiring Phase I per Operating Limitations. Again, I know other FSDO's have made different ruling on same question but that's the answer I got from mine.

Hope the change goes smoothly and look forward to reading the results.
 
Bob'sRV6A said:
FYI there is a string of replies to my question on the aeroelectric-list about the best way to wire the p-mag in light of the simple wire squash connections. I am going with the ferrules. http://forums.matronics.com/viewforum.php?f=3

Bob
Click to expand...
Good info.

When I first installed my P-mags, I "tined” the leads on all the wires. On the right P-mag, one of the wires broke at the end of the solder. I clipped all those wires back on just the right P-mag and reconnected them. I’ve been running over 250 hours with one P-mag with tined wires and one without, all without problem. Go figure.

One thing I did do, that I think helps, is to put two layers of shrink tubing over the wires where they pass through the Adel clamp. This keeps the wires from moving and breaking. For those of you who are already flying, just remove the Adel clamp and wrap the wires in the fat rubber electrical tape. That will work just fine and you won’t have to disconnect the wires from the P-mags.


(Click to enlarge)

Note the ground wire going to a case bolt. DO NOT run your ground to the firewall and DO NOT run the grounds from both P-mags to the same case bolt. They are supposed to be grounded to the case and independent of each other.

Note 2: See how Adel clamps were used to secure the vacuum lines for the P-mags across the top of the engine mount.
 
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OneCharlieKilo said:
...Brantel,
Have you checked with your FSDO on whether this is considered a "major" change that requires a 5 hr Phase I test period?
...
Click to expand...

EAA does not consider this a major change, and I had to agree - there's no significant CG, engine operation, or pilot interface difference. I never talked to the FSDO. Since it boils down to "personal opinion" at the FSDO, I stuck with the personal opinion I trust most, my own.
 
I tend to agree, my engine lost it's certified status many moons ago. I think as a whole, we tend to ask our FSDO's for permission too often. I try to limit my communication with them. Seems the more we talk to them, the more power they have over us since they tend to make up their own rules as they go.

Ask 10 of them about this and you will get 10 different answers. What do the regs say? Thats the approach I take.

My op limits allow me to flip back into phase I if I want. There will be testing but most likely this change won't require a re-entry into phase I that is my decision not their's according to my op limits.
 
N941WR said:
Note the ground wire going to a case bolt. DO NOT run your ground to the firewall and DO NOT run the grounds from both P-mags to the same case bolt. They are supposed to be grounded to the case and independent of each other.
Click to expand...

Bill - that's a good catch. I had planned to run ground wires to my firewall "forest of tabs" ground block. I wonder why they want to use the engine case? In general, it is a "worse" ground than the firewall, where the battery connects.
 
IowaRV9Dreamer said:
Bill - that's a good catch. I had planned to run ground wires to my firewall "forest of tabes" ground block. I wonder why they want to use the engine case? In general, it is a "worse" ground than the firewall, where the battery connects.
Click to expand...

The tabs can break as can the ground wire back to the engine.

I used the closest case bolt I could find. Remember, for the P-mags you are trying to ground them to the engine, the airframe really doesn't matter, as you want to make sure the engine continues to run at all times, even if everything on your panel goes dark.

Don't forget to clean the paint off under the case bolt.

Also check out the second note I added to my post above.
 
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Brantel said:
...

Hope to install it this weekend!!!


Now what are the suggestions??? Run in Mag mode, A curve, B curve or modified B curve and if the later, what do I modify? I have a carbed O-360 with 8.5:1 pistons and a FP prop....
Click to expand...
How many hours do you have on your engine?

For new engines with less than ~15 hours I recommend putting the jumper in, forcing it to the A curve and plugging the vacuum line. This will hold the timing right at 25*BTC.

If you have more time on the engine, start buy connecting vacuum line. This will allow the P-mag to advance as your power drops off. High power settings will keep the advance at or close to 25 and as you climb, the P-mag will advance the timing as MAP drops off.

Once you get a base line there, remove the jumper and see what happens. Starting timing is close to 29* BTC on the B curve.

Depending on your results, you can reduce the B curve, if needed.

When you start running on the B curve, expect your CHT's to go up and your EGT's to go down. The reason is that you are burning more of the fuel-air mixture in the cylinder before the exhaust valve opens.

If you have an EICommander installed, you can make these adjustments from the cockpit. If you want, you can even make the adjustments in flight. That's in addition to the EICommander being an EMS for your ignition system.
 
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IowaRV9Dreamer said:
Bill - that's a good catch. I had planned to run ground wires to my firewall "forest of tabs" ground block. I wonder why they want to use the engine case? In general, it is a "worse" ground than the firewall, where the battery connects.
Click to expand...
Dave,

I checked with Brad and Tom. What follows is a summary of their reply:

Emag recommends the case for a couple of reasons. First, there have been builders who left off the grounding cable or had it break and under starting loads, the current will travel through any path it can. When this happens, it would toast the P-mag. With the 114 series, they added an internal ground to keep these loads from frying the electronics inside the ignitions. Ground to the engine will prevent this problem, should the ground strap become disconnected.

With this internal ground, loosing that ground wire will not prevent the P-mag from continuing to fire your engine, if this happens while it is running.

Because they use the block as the return path for the spark energy, if the P-mag is not grounded to the engine, it does not affect the spark plug firing.

Hope this helps clear this up.
 
Finished up the P-Mag install today. It took a few more hours than advertised...

Making new plug harnesses - slow but not hard, follow their directions on the lube and it goes OK
Adding power switch-wire-fuse to panel - hate under the panel work!!! Hate drilling new holes in the panel!!! Hate digging shavings out of the carpet!!!
Reworking p-lead switches - I used toggle switches, had to remove the starter block on the right mag switch and remove the tach wire from the right p-lead
Running tach wire thru firewall - upside down under the panel feet hanging over seats!
Running power wire they firewall - upside down under the panel feet hanging over seats!
Splicing into MAP line - required trip to autoparts store for "T"
Drilling firewall for MAP line - Did not want to mess with the braided line fwd of firewall so I decided to make the connection inside where the tubing is and after the restrictor to make it smooth for the P-mag.
Removing right mag harness - mostly painless
Reworking left mag harness to only fire bottom plugs - somewhat painfull, had to cut all the ties and mounts lose and rework
Remove old top plugs - old plugs look like they were buring as good as I could ask for. Nice and clean and good color. Good sign the engine is running good.
Anneal plug gaskets - The auto plug adapters were advertised to come with new gaskets but they did not so I had to reuse the old ones. No big deal, easy to anneal them.
Remove drive gear from mag - Requires a couple small strap wrenches and a gear puller. The mag shaft does not have a dimple in the end so we used the original nut to hold the puller shaft. Popped off with a bang!
Add drive gear to P-mag - Easy as pie but takes a couple times to get the cotter pin hole to align.
Stab in the P-mag - Plenty of room between the P-mag and the battery box.
Makeup wiring connections to P-Mag. Used lots of heat strink and ferrules. Took my time to ensure no issues down the road.
Time P-mag. Super easy! Set TDC, blow into the MAP tube twice and you are done!
Add new plug wires - Had to drill out the plug wire shields, come up with new bracing locations, add zip ties to prevent them from touching each other and causing inductive coupling missfires.
Gap plugs - I used the cheap NGK BR8ES plugs @ .0325", was going to use Iridium but could not find them locally??
Test ignition - Big fat long duration starting sparks!!! Sounds like buzzing RF arcs during start mode!
Install plugs - Used anti-seez and torqued the plugs not the adaptors. Installed the adaptors on the plugs first.
Test run!!!

Started pouring rain before I could test fly but the ground test runs went perfectly.
 
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Test run report:

First start with a cold motor was withing 2 blades.
P-mag can self power itself down to 800rpm.
Second start with warm motor was 1 blade.
Third start was instant to 1 blade. Pretty much starts like a late model car.

Mag checks @ 1700 rpm reveal:

P-mag off, regular mag on = 40rpm drop
regular mag on, P-mag off = 10rpm drop

Prior to the P-mag swap, I would get 40 rpm drops on both mags.

At 800 rpm idle, I get what I would call weird results. At this low RPM, if I turn off the regular mag, I get a large drop in RPM. If I turn off the P-mag, hardly any drop. At idle speeds, I see the opposite of what I see at runnup RPM. Maybe some of you smart guys can explain this to me??

With both traditional mag and P-mag on, I can idle ultra smooth down to 625 rpm. That is against the stop so it may even go lower, iduno??

The only thing that makes me a little concerned on this install is the auto plug harnesses. I have complete faith in the connection to the plugs since they really snap onto the plugs but the connection to the P-mag coil housing is not as robust. I can see one of them working lose... Anyone ever had this happen?
 
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Brantel said:
...The only thing that makes me a little concerned on this install is the auto plug harnesses. I have complete faith in the connection to the plugs since they really snap onto the plugs but the connection to the P-mag coil housing is not as robust. I can see one of them working lose... Anyone ever had this happen?
Click to expand...

Though they are small, the connectors still have a pretty positive "snap" to engage... Are you sure they are seated? Also, after a while the boot will likely "glue" itslef to the tower. Not enough to prohibit removal, but it will take a little work down the road. To answer your question, I've never had any come loose in the 250 hours I've been running P-mags (auto connectors on both ends).
 
Ya, I made sure I heard them click when installing...

Toobuilder said:
Though they are small, the connectors still have a pretty positive "snap" to engage... Are you sure they are seated? Also, after a while the boot will likely "glue" itslef to the tower. Not enough to prohibit removal, but it will take a little work down the road. To answer your question, I've never had any come loose in the 250 hours I've been running P-mags (auto connectors on both ends).
Click to expand...
 
Two test flights today with my new P-mag.

This thing worked exactly as advertised....

First flight was with the "A curve" select jumper installed because I wanted to see what this ignition advance stuff was going to do to my CHT's before going for the full "B curve".

"A Curve" went just fine. First start this morning was instant. Pretty cool since the OAT at that time was 32°F and the low last night in my unheated and uninsulated hangar was 15°F. I do have a sump heater though and it was running last night.

CHT's were fine and the engine ran noticably smoother. Hard climb on TO, climb to 5500 and tested the leaning ability. I can now lean way past peak with no stumbles whatsoever. Remember I have a CARB!!! The engine just starts to slow down, no stumbling!!! EGT's went down on average, not much change in CHT.

Idle can get down to scary low speeds with this thing!


Second flight I pulled the jumper and flew with the "B Curve".

This flight went just as well. I did a climb all the way to 8500ft this time and ran the test runs at WOT. CHT's may be a little higher than before average but not too bad. EGT's dropped around 100°F average. At best power mixture @ 8500ft DA, I could get around 2650rpm max on my FP prop. Leaning still worked just as good as the "A Curve". I do not think the airplane is any faster but it sure feels meaner. You can actually feel the way the ignition advance makes the engine hit harder.

Idles so slow it is scary!!! Almost sounds like it has quit!

So far I am a happy camper!!


Has anyone played around with increasing the Max Advance Limit or increasing the Constelation/Overall Advance of the "B Curve" beyond the default?
 
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