Electroair EIS installed

[kevinw]

Well I finally broke down and installed the electroair EIS41000 electronic ignition system in my '82 J. First a little history on this plane; I bought this after a pre-buy with another buyer discovered a crack in the engine block. The buyer and seller couldn't get together on price and that was the end of it. I stumble along and like the airplane but the problem is I can't fly it. Trusting the broker who knows the seller well and has flown the airplane dozens of times, I buy the airplane for what I believe a very reasonable price. I converted the engine from the A3B6D to the A3B6, overhauled the prop and govenor, installed a JPI EDM700 and off I went with a zero time engine and prop in my new airplane. I'm going on two years now and the airplane has lived up to nearly all my expectations and has given me few problems. The reason I bring this up is the true airspeed. Both the broker and later the seller told me this airplane has a TAS of about 155. Since I've owned it I'm normally around 150-152 tops. I've often wondered if the A3B6 is the reason because the mag timing is set at 20 degrees BTDC. I also know I'm losing about 5 knots because of the TKS. Today I flew the airplane for only the second time since installing the EIS and I have to say I'm pleased. First of all starting is much easier than before. I've had problems previously (probably pilot error) but those are now a thing of the past. The first thing I noticed is the engine makes a distinctly different sound; it's not only smoother but just different. Because the weather changed significantly from the time it went into the shop to the time I got it back performance is a little difficult to compare. Taxiing out to the runway I find I can have the throttle completely out and the engine runs smooth at about 700 rpms. Before the EIS it would sputter a bit, even when aggressively leaned. Run-up is normal except now when I do the mag check I first kill the EIS with a second red Mooney rocker switch that was installed in the panel, rpms drop about 100 and I turn it back on. Takes a second for the EIS to fire again. Then I turn the rotary to R which shuts off the remaining left mag. I see a drop of maybe 20-25 rpms; hardly noticeable. Then back to both setting and rpms come back. After finishing the checklist I'm off. Full throttle and once again, clearly a different engine sound at the higher rpms and much smoother. The rate of climb is better but I honestly believe that's due the the colder temperature. At 3500 ft I leveled off for the short flight. CHTs and EGTs seem to be the same as before but once again, it's 30 degrees colder now. What I did notice is the TAS of 155. That was a nice surprise that I didn't expect. I'm wondering if this system increases the speed/performance more in the A3B6 than the A3B6D. I'm not a mechanic or even close but the D has the timing set at 25 degrees BTDC versus 20 degrees in mine. Perhaps someone with more of mechanical background can try to make sense of this. Fuel burn was the same as before but it will be interesting to run this at 8-10K feet and see how it does. One last thing. Today when I took off the airport manager, who is also my instructor, was walking outside and said the engine noise was noticeably different than before from the ground as well. He said it was not only smoother, but also quieter.

 

I know this upgrade will never pencil out dollar-wise but I didn't expect it to. I simply wanted an airplane that was easier to start and ran smoother and I definitely have that now. Last year I had my prop dynamically balanced and that took care of a lot of vibration. Now that I've added the electroair my J is the smoothest running piston single I've been in. So far I'm very pleased and looking forward to giving more pireps when I put more hours on it.

 

Kevin

[Cruiser]

according to the install manual your unit is preset.

 

"Calibration and Timing settings: Your unit has been pre-set at the factory for a base

timing of 25 deg BTDC (base timing is always placarded timing for the engine). "

 

you might check with your installer, if they didn't change it you are getting the benefit of electronic advanced timing.

With new harness and plugs you most certainly should see a performance boost.

[kevinw]

 

according to the install manual your unit is preset.

 

"Calibration and Timing settings: Your unit has been pre-set at the factory for a base

timing of 25 deg BTDC (base timing is always placarded timing for the engine). "

 

you might check with your installer, if they didn't change it you are getting the benefit of electronic advanced timing.

With new harness and plugs you most certainly should see a performance boost.

 

The installer discovered this during installation and sent the unit back to be re-calibrated. In hindsight I could saved some time and ordered it from the factory with the correct calibration (had I known). Problem is, the system is about $400 less at aircraft spruce than from the factory.

[kmyfm20s]

Did you choose to have the EI connected to all your lower plugs? They say the EI is less prone to plug fowling.

[kevinw]

Did you choose to have the EI connected to all your lower plugs? They say the EI is less prone to plug fowling.

Yes I did. Originally he was going to install two on top and two on the bottom but I questioned it because all of my research said to do it the way you describe. After talking about it he agreed.

Sent from my iPhone using Tapatalk

[carusoam]

Fine wire plugs and E-ignition can eliminate the 'need' to balance top/bottom plugs on each mag.

That would be a nice benefit.

Keep on sharing your E-experience.

The 25° timing would be a bonus. (Byron?)

Best regards,

-a-

[jetdriven]

the 25 degrees itself is worth 3-5 knots. I've seen it.

 

Kevin, is your unit set to 25 degrees or 20 degrees?

 

One more thing, I've mentioned before. The service instruction for 20 degrees timing is just that, a service instruction. You can undo it by installing the correct P/N magneto for 25 degrees timing and restampign the data plate to 25. Its on the 1E10 Type Certificate after all. Get all the HP you paid for.

 

For the naysayers NASA published an emissions paper on Lycoming engines. The O-320 made more power at 25 degrees than 20.

[ryoder]

Thanks for the review.

[kevinw]

the 25 degrees itself is worth 3-5 knots. I've seen it.

 

Kevin, is your unit set to 25 degrees or 20 degrees?

 

One more thing, I've mentioned before. The service instruction for 20 degrees timing is just that, a service instruction. You can undo it by installing the correct P/N magneto for 25 degrees timing and restampign the data plate to 25. Its on the 1E10 Type Certificate after all. Get all the HP you paid for.

 

For the naysayers NASA published an emissions paper on Lycoming engines. The O-320 made more power at 25 degrees than 20.

The unit is set from the factory to 25 degrees but my engine is set for 20. The installer called electroair and they had him send the controller in to be reprogrammed for 20 degrees. Perhaps we shouldn't have done that. Did I just give up some power by doing so?

[kmyfm20s]

The unit is set from the factory to 25 degrees but my engine is set for 20. The installer called electroair and they had him send the controller in to be reprogrammed for 20 degrees. Perhaps we shouldn't have done that. Did I just give up some power by doing so?

Probably for take off at sea level but the EI should advance the timing as altitude get higher(MP lower) and make the 20 degrees irrelevant.

[kmyfm20s]

Secound thought, unless it's a linear 5 degrees through out he EI's advancing. You might have given up something. I'm no expert by any means.

[kevinw]

Secound thought, unless it's a linear 5 degrees through out he EI's advancing. You might have given up something. I'm no expert by any means.

It would be easy to have it reprogrammed back to 25 degrees. As Byron posted, then I would need the correct p/n mag and restamp the data plate. Just wouldn't want to go through all the work if it didn't make much of a difference. I'm going to look into this further. Thanks for all the advice guys! 

[kevinw]

Secound thought, unless it's a linear 5 degrees through out he EI's advancing. You might have given up something. I'm no expert by any means.

I think you were right on your first post. Because the timing advance is based on atmospheric conditions and rpm I don't think pre-set timing matters at altitude. The EI is going to fire at the peak pressure point. Here's an excerpt from the installation manual online:

 

At any altitude, a cylinder on the intake stroke draws in fuel and air. At lower altitudes, on the 

compression stroke (as the piston moves up) at the preset degree before the piston reaches 

the top of the cylinder (TDC), the spark plug fires lighting the air/fuel mixture. The objective is 

to reach the peak pressure point (as a result of igniting the air/fuel mixture) by the time the 

piston reaches 11 to 17 degrees past TDC.

 

As altitude increases, thinner air reduces the oxygen available for the proper fuel-air mixture 

creating more space between the air/fuel molecules. When the spark plug fires at the preset 

degree before TDC, the thinner air/fuel mixture will burn slower. Therefore, the peak pressure 

point occurs much later than 17 degrees past TDC, and hence there is a loss in power. By 

advancing the timing based on RPM and atmospherics, the peak pressure point can be 

maintained much closer to 11 to 17 degrees after TDC. 

[carusoam]

Firing at peak pressure sounds ideal... Too ideal...

The reason for firing before top dead center is it takes time for flame propagation.

The flame should be fully propagated after the peek pressure point.

That firing time is measured in °BTDC. This also includes RPM into the time equation.

Unfortunately, the discussion is too complex for me and my single finger typing...

If 25°BTDC gives best HP, that is where I would want to be, accept for start-up and taxiing...

Definitely seek additional input to avoid giving away the extra HP.

The value of the extra HP for an O1...10% more HP equates to a 400' shorter T/O distance and improved climb... (The only example I have)

Some costs to consider, change to FF, extra HP comes at a defined cost. CHTs tend to increase in a same predictable manner.

5% more power would use 5% more fuel generating 5% more heat without changing the cooling capacities an equal 5% without increased CHT... Something like that.

Fortunately, you can always bring the throttle back 5%...?

How does that sound?

Keep in mind I am only a PP, not a mechanic, and I do like high HP/weight ratios...

Best regards,

-a-

[philiplane]

The unit is set from the factory to 25 degrees but my engine is set for 20. The installer called electroair and they had him send the controller in to be reprogrammed for 20 degrees. Perhaps we shouldn't have done that. Did I just give up some power by doing so?

The 200 HP Lycomings with two magnetos are all set at 20 degrees BTC initial timing. The 150-180 HP Lycomings are set at 25 degrees due to their lower mechanical compression ratios. The magnetos for each engine will have a corresponding impulse coupling lag of 20 or 25 degrees so the engine fires at TDC during starting.

[N601RX]

The 200 HP Lycomings with two magnetos are all set at 20 degrees BTC initial timing. The 150-180 HP Lycomings are set at 25 degrees due to their lower mechanical compression ratios. The magnetos for each engine will have a corresponding impulse coupling lag of 20 or 25 degrees so the engine fires at TDC during starting.

Simply not true. There are plenty of 2 mag 200 HP lycomings legally set to 25 deg.

[philiplane]

The standard timing was 25* btdc and the change was to 20*btdc. The SI that deals with the change said it was done primarily to reduce CHT's in cruise and to increase detonation margin during cold weather operation at high power. It's Lycoming SI 1325A if you are interested.

 

This Lycoming service instruction calls for changing the timing, due to problems at extreme cold temperatures, and every angle valve 200 hp engine since has been built by Lycoming at 20 degrees, and now they claim it actually makes equal or better power at that setting.
The 25 degrees was in use when Mooney selected the IO360A1A for the E model in 1963, before the A3B6 or A1B6 were on the drawing boards.
Also, the A1B6(and A1B6D) was first used on the C177RG in 1971, then adopted by Mooney in 1976, then converted to A3B6D by changing prop orientation for slightly smoother operation. In other words, the A3B6D wasn't even the original application for the engine

[jetdriven]

Not every angle valve engine. That SI, and the 1E10 Type Certificate, state that the 20 degrees is optional for all IO-360 engines except the IO-360-A1B6D and -A3B6D.   Those are required to be at 25 degrees. What I would like to know is how it makes 200 HP at 25 degrees, but when you put two mags on the accessory case, then reset the timing to 20 degrees the power is the same. The ROC and speed are not.

 

I dont believe the IO-360 made over 200HP at 25 degrees, and 20 degrees is still "good enough", either.  For example, the IO-390 is 210 HP, but it carries a 5-minute takeoff power limit, followed by 27.2" continuous. They are that concerned for the longevity of the engine at elevated power output.

[philiplane]

The single mag engines are all 25 degrees, probably because the magneto is crap to begin with.

 

There's also an STC for the 200 HP engines to increase the HP to 210 by using the higher compression helicopter pistons. It requires 20 degrees timing.

[carusoam]

Setting timing for detonation margin during cold ops at low density altitudes sounds nice...

As an educated PIC, I would prefer to maintain the margin myself... What if I only fly high density altitudes on summer days...?

As an engine builder, I would expect too many customers to be unable to maintain a proper margin from pre-ignition...

The amount of power available on cold days is somewhat impressive, my C gave a noticeably different take-off run at 20°F, near sea level.

The advice I was given (primary training), was to not exceed a particular MP on cold days... (Is this valid?)

The other advice from the engine builders is based on single CHT and single EGT instruments without knowing much about the actual cowl / cooling.

What do the -20°F pilots do in this case?

Fortunately, with better instrumentation and better shared knowledge, our margin gets minimized...

Keep sharing,

-a-

[BorealOne]

Any recent updates from the field, Kevin?

 

Yes I did. Originally he was going to install two on top and two on the bottom but I questioned it because all of my research said to do it the way you describe. After talking about it he agreed.


Sent from my iPhone using Tapatalk

[Culver LFA]

There's also an STC for the 200 HP engines to increase the HP to 210 by using the higher compression helicopter pistons. It requires 20 degrees timing.

Is it this one? http://thenewfirewallforward.com/linked/tnfwf_horsepower_plus_stc.pdf

[aaronk25]

Read some reviews of customer service and I'm guessing you wouldn't touch that company with a 10' pole....

[kevinw]

Any recent updates from the field, Kevin?

my plane has been in the shop the last several weeks. When I get it back I'm plan in a trip far enough to get it up to 10-11K to really see how it performs. Between work and a busy life I haven't had a chance to fly any distance to give a pirep. As far as smoothness and ease of starting I'm very happy. I don't want to suggest it starts like a car but ever since its been installed I've never had a problem getting it lit. I'll report back soon!

Sent from my iPhone using Tapatalk

[kmyfm20s]

my plane has been in the shop the last several weeks. When I get it back I'm plan in a trip far enough to get it up to 10-11K to really see how it performs. Between work and a busy life I haven't had a chance to fly any distance to give a pirep. As far as smoothness and ease of starting I'm very happy. I don't want to suggest it starts like a car but ever since its been installed I've never had a problem getting it lit. I'll report back soon!

Sent from my iPhone using Tapatalk

Any updates?