Short shielded plugs?

[mhorowit]

On two occassions folks have mentioned a short version of the REM40E sparkplug, which can be used in the upper cylinders to avoid using cans or bumps in the cowl.
Looking in Spruce, I see UNISON describing a plug thusly: "minimum plug length allows for greater clearance between the plug and aircraft cowling".

Does anyone know if this plug provides the needed clearance? - Mike

[David Price]

Mike,
I believe that the harness has to be changed also to allow for the differance in connection height and angle. They have a 90* connector to help lower the profile of the harness connection.
This is an area of concern to me also, as would like to do away with the bumps. The orignial cowling shape and style is very clean.

What say all?
Who knows the answers?

[stormman]

short spark plug

find it hard no one replied that the champ REM37BY is the plug your looking for

[paulp]

plugs

Norm,

Do the REM37by plugs require a different harness than that used for the REM40E plugs? I would like to shave my cowl bumps but I just bought a new harness and all new REM40E's.

[stormman]

Plugs, spark

No , the E in REM means shielded 5/8 thread harness.

the 37 means its a colder plug . So if i were you i would just use the 37BY in the top plug holes

[AndyDuke]

Storman,

What do you mean by a colder plug?

[David Price]

Don't think he means that the plug needs a sweater or a coat or a blanket!
Just that the ignition temp. of arc in "colder" than the ignition temp of an REM40E.

But hell, I been kown to be out of order and wrong in the past too.

NORM, how am I doin'?

[stormman]

cold plug

Doing fine Dave, dropin anytime

Dave's Right
Plug designers can make plugs of different heat ranges
Cold ones for hot high compression engines with hotter internal exhaust temps and hotter ones for low compression engines like the A65 which would foul and short out a cold plug if ran too rich. If a plug is too hot it can melt and the electrode would fall into the cyclinder and maybe break a valve amoung other things. short sparkplug life being one of them

Kinda of like old girl friends. the hot ones were a lot hotter back then but burnt out fast! The cold ones lasted longer, might have something to do with the sweater

[mhorowit]

What document would I go to to see that it's OK to use the 37BY in the A-65? - Mike

[David Price]

On that one I will admit that I do not know the answer.
Soooooo.. I bow to expertise.

A little research should turn up a positive leaf.

It's Mother-In-Law's Birthday and off to clelbrate with dinner.

[David Price]

But before I go!

NORM,
It is the sweaters for a fact

[AndyDuke]

Thanks, helps clarify a few points. You should use the engines type certificate to find the plugs that can be used with the engine. For mine (a C85) the certificate lists all the approved spark plugs, by manuufaturer.

I checked and the Champ REM37 is not listed as approved for the C85. You had better check the the STC for the A65.

[stormman]

Spark Plugs

Better check the champion list as its a new plug
That diasour C85 has list not been updated in a zillion years

[Rusty Coonfield]

My experience with talking to Fresno Air parts is that there IS a shorter shielded plug but it is not short enough! The solution is to use unshielded plugs with "aircoupe" cups. the cups provide a lower profile shielding system that will fit under the cowl. Mine were really tight and had to shave some of the cups themeselves to get them to fit properly!

[robbie]

Were did you find the "aircoupe" cups??