Spark Plugs -- Massive or Fine Wire

[Andy95W]

5 hours ago, Yetti said:

If the cylinders are getting oily you can go with the BY Champion that has a longer nose on some 4 cylinder Lycomings.

Exactly the way I feel now (except not the Champion.)

I'm currently running Tempest fine wires in my bottoms and Tempest massives in the tops.  When it comes time to change, I'm going with Tempest BY plugs all around.

[PT20J]

12 hours ago, M20Doc said:

Not really sure I can convince you, I might have more luck with the argument that a Comanche is better than a Mooney!

Well, maybe it's just a good copy. The Mooney engineers used to tell how Piper was looking for a competitor to the Bonanza and wanted to buy the Mooney design. Supposedly, Mooney flew a plane to Lock Haven and while Mooney and Piper were having lunch, the Piper engineers swarmed the M20 with cameras and tape measures. I have no idea if this story is true or not. However, the two airplanes bear an uncanny resemblance: they have similar dimensions, the same forward swept wing, similar airfoils and the planforms lay over each other amazingly well with the exception of the empennage.

[Guest]

The first Comanches even had Mooney style trailing link gear, thankfully Piper saw the light and went with oleo landing gear, fuel bladders and zinc chromate primer throughout. 

Clarence

[Guest]

I finally got to fly with the new Tempest fine wire plugs.  I’d say is starts more quickly than ever before, the mag drops at run up are lower and it seems smoother in flight.

Clarence

[Danb]

2 hours ago, M20Doc said:

I finally got to fly with the new Tempest fine wire plugs.  I’d say is starts more quickly than ever before, the mag drops at run up are lower and it seems smoother in flight.

Clarence

my thoughts also Doc,my hot starts improved significantly

[M20F]

On 2/15/2019 at 2:09 PM, Bob_Belville said:

In my personal experience fine wires are cheaper than massive. In cost per hour, of course.


Sent from my iPad using Tapatalk

Till you drop one on the ground. 

[Bob_Belville]

5 minutes ago, M20F said:

Till you drop one on the ground. 

True, but why would you drop a $100 spark plug? Or your wife's favorite tea cup? It's okay to drop a hammer, but a hammer won't deliver forty 30,000 V sparks every second.

[M20F]

6 minutes ago, Bob_Belville said:

 It's okay to drop a hammer, but a hammer won't deliver forty 30,000 V sparks every second.

Just depends on what you drop it on :-)

[jaylw314]

34 minutes ago, Bob_Belville said:

True, but why would you drop a $100 spark plug? Or your wife's favorite tea cup? It's okay to drop a hammer, but a hammer won't deliver forty 30,000 V sparks every second.

I'm sure (almost) everyone who has ever dropped a fine-wire plug did not wake up that morning thinking to themselves, "hey, you know what, I'm going to live a little today and drop a fine-wire spark plug" 

[Bob_Belville]

4 hours ago, jaylw314 said:

I'm sure (almost) everyone who has ever dropped a fine-wire plug did not wake up that morning thinking to themselves, "hey, you know what, I'm going to live a little today and drop a fine-wire spark plug" 

Sure. But it seems like every time the fine wire vs. massive comes up someone will argue that the loss from dropping a plug is a reason to stick with massives. I don't think that's a logical argument. I could as easily argue, and I think it's true, that I'm more careful handling fine wire plugs so to return to my original assertion fine wires are still cheaper since I will drop fewer of them.  Only half kidding.

[Guest]

9 hours ago, M20F said:

Till you drop one on the ground. 

The price is a strong motivator for not dropping them.  

Clarence

[RLCarter]

My thought is if its common for you to drop your plugs, fine or massive you might want to rethink handling them or anything else of value

[EricJ]

I was getting frequent fouling in one of the bottom massive plugs, so switched all of the bottoms out for Tempest fine wires.   I had one of the fine wires foul once since then and it burned off easily on a runup.   Totally worth it.

 

[squeaky.stow]

I bought Tempest Fine Wires on the basis of recommendations here on MS. 

When I bought my 252 it would not run smoothly LOP at higher altitudes despite having a GAMI spread of .5 or less. 

I did two things.

1) Got the mag timing adjusted. (Helped a bit)

2) Installed Fine Wires. (Helped a lot)

Based on the type of flying I do, which is 600 mile trips to the east coast, the plugs have already paid for themselves in fuel savings by allowing me to run LOP. If I did mostly short local hops, or only ran ROP, I am not sure I could justify the additional cost.

Mark

[dmc]

On 2/23/2019 at 6:48 AM, M20Doc said:

I finally got to fly with the new Tempest fine wire plugs.  I’d say is starts more quickly than ever before, the mag drops at run up are lower and it seems smoother in flight.

Clarence

I wonder if new massive might give you the same results.  I assume you were replacing older plugs.

[Bob_Belville]

7 minutes ago, dmc said:

I wonder if new massive might give you the same results.  I assume you were replacing older plugs.

There's hardly any such thing as an older massive plug.  I'm going to guess that Clarence knows how to read a tach... "mag drop lower". 

[dmc]

13 minutes ago, Bob_Belville said:

There's hardly any such thing as an older massive plug.  I'm going to guess that Clarence knows how to read a tach... "mag drop lower". 

If the plugs being replaced had say 500 hrs on them they may not have been performing as new.  Did he replace new massives with new fine wires?  If he did then there was definatly an improvement for him.  Or were the plugs he replaced just worn?

I called Tempest and asked what the difference was in their plugs.  They only said that the fine wires lasted longer, that iridium was expensive, and they didn’t sell as many, thus the higher cost.  They did not claim that they performed better.

Edited February 24, 2019 by dmc

[Guest]

1 hour ago, dmc said:

I wonder if new massive might give you the same results.  I assume you were replacing older plugs.

It’s possible, however I was replacing a set of Champion fine wire plugs that had cracked electrodes and higher than normal resistance.

Clarence

[PT20J]

I spoke with Joe Logie from Champion Aerospace at a trade show yesterday. He had a cutaway of Champion's improved massive electrode plug with the molded-in resistor (no more resistor/spring/screw). I'd be willing to bet these are as good as the Tempest plugs. Anyway, I got a set with my factory rebuilt Lycoming IO-360-A3B6, so I'll keep a check on the resistance and see how they age.

I asked about fine wires vs. massives. His take is that there is a theoretical advantage because, especially when new, the spark may jump the gap deeper in the plug closer to the insulator on a massive electrode plug. As the electrodes wear, the bending adjustment to close the gap causes the spark to be more likely to occur nearer the tip. So, maybe worn out plugs perform better? This is all theory -- there's no data. He did say you could get the same effect at lower cost with the BY plugs for engines that will accept them (the angle valve Lycoming IO-360s will not). He said Champion  recommends the fine wires for engines that are oily, run several hundred hours per year, or have plugs that are difficult to remove (rear plugs on radials for instance).

Skip

[Andy95W]

30 minutes ago, PT20J said:

I spoke with Joe Logie from Champion Aerospace at a trade show yesterday. He had a cutaway of Champion's improved massive electrode plug with the molded-in resistor (no more resistor/spring/screw). I'd be willing to bet these are as good as the Tempest plugs. Anyway, I got a set with my factory rebuilt Lycoming IO-360-A3B6, so I'll keep a check on the resistance and see how they age.

Joe is knowledgeable but he’s also there to sell stuff for Champion. For me, they lost my business when their products became substandard and they kept insisting that they weren’t. And Joe was one of the people insisting that spark plug resistance didn’t matter- until they changed their design.  He also insists that Slick mags are just as good as Bendix, but won’t address the parts issues they’ve been having with things like coils and drive gears.

Like you, I’d run them if they came with the engine, but when they needed replacing I’d buy Tempest. 

Nowadays when I see Joe at OSH I try not to make eye contact. 

[Culver LFA]

Just now, Andy95W said:

Joe is knowledgeable but he’s also there to sell stuff for Champion. For me, they lost my business when their products became substandard and they kept insisting that they weren’t. And Joe was one of the people insisting that spark plug resistance didn’t matter- until they changed their design. 

Like you, I’d run them if they came with the engine, but when they needed replacing I’d buy Tempest. 

Nowadays when I see Joe at OSH I try not to make eye contact. 

I was just going to post pretty much the same statement, "when their products became substandard and they kept insisting that they weren’t."

[Guest]

1 hour ago, PT20J said:

I spoke with Joe Logie from Champion Aerospace at a trade show yesterday. He had a cutaway of Champion's improved massive electrode plug with the molded-in resistor (no more resistor/spring/screw). I'd be willing to bet these are as good as the Tempest plugs. Anyway, I got a set with my factory rebuilt Lycoming IO-360-A3B6, so I'll keep a check on the resistance and see how they age.

I asked about fine wires vs. massives. His take is that there is a theoretical advantage because, especially when new, the spark may jump the gap deeper in the plug closer to the insulator on a massive electrode plug. As the electrodes wear, the bending adjustment to close the gap causes the spark to be more likely to occur nearer the tip. So, maybe worn out plugs perform better? This is all theory -- there's no data. He did say you could get the same effect at lower cost with the BY plugs for engines that will accept them (the angle valve Lycoming IO-360s will not). He said Champion  recommends the fine wires for engines that are oily, run several hundred hours per year, or have plugs that are difficult to remove (rear plugs on radials for instance).

Skip

I believe that BY plus are approved for IO-360 series.

https://www.lycoming.com/sites/default/files/SI1042AG Approved Spark Plugs.pdf

 

[PT20J]

2 hours ago, M20Doc said:

I believe that BY plus are approved for IO-360 series.

Interesting. Here's the Champion chart. I checked the Tempest chart and it agrees with Lycoming.

[PT20J]

3 hours ago, Culver LFA said:

I was just going to post pretty much the same statement, "when their products became substandard and they kept insisting that they weren’t."

My experience is that pretty much no company will admit they ever made an inferior product. I don't know why. Once you have a better replacement, being honest helps rebuild trust. Denials in the face of evidence to the contrary never makes the problem go away (I know this from experience: my career was in tech product development). We have literally a 5 gal bucket at the museum full of Champion massive electrode plugs that have >>5K ohm resistance that we've removed from the B-25, DC-3, Tigercat and all the other airplanes. We remove them from service because high plug resistance can cause insulation breakdown (punch through) in the shielded ignition harness. Want to have a really bad day: try replacing ignition leads on a radial engine. Joe did offer that Champion would replace the resistors in them at no charge if we returned them, but the design is bad and they'd just fail again. Now, if Champion would replace them with the new design, we might have something to talk about. But, we've long ago switched to Tempest; massives in the front and fine wire in the rear (we remove and gap the fronts every year to do the compression test at annual inspection, but we seldom remove the rears as they are a PITA to get to. There is no need to rotate plugs on a radial -- odd number of cylinders).

 

[Cyril Gibb]

15 hours ago, PT20J said:

Interesting. Here's the Champion chart. I checked the Tempest chart and it agrees with Lycoming.

That chart is (at least) incorrect for my IO360-A1A.  I use BY plugs.  Experience has shown me when I see an error in a document, I question the remainder.