YIO390 EXP w/E Mags

[rockitdoc]

My 390 came with two E Mags and Denso IKH27 plugs. They were gapped 0.030" from Lycoming. I presume this is correct, but I can't find anything in the Lycoming manual on this.

 

[georgemohr]

My 390 came with two E Mags and Denso IKH27 plugs. They were gapped 0.030" from Lycoming. I presume this is correct, but I can't find anything in the Lycoming manual on this.

Yeah, and suggest you download the EMag manual. It has this and a lot of other great info.

 

[Walt]

Suggest Jumper in and retard 5-10 degrees from '0'.

 

[georgemohr]

Suggest Jumper in and retard 5-10 degrees from '0'.

5-10 is a big jump. Just curious why so much in your view? CHT purposes? TY! -G

 

[Full Throttle]

The torque curve on a Lycoming Hemispherical combustion chamber piston engine is very flat at maximum torque. More advance timing only brings it closer to detonation and raises cylinder temperature without much in the way of more horsepower.

 

[Walt]

What Full Trottle said, no advantage to lots of advance, plus:
Spec is 20* on angle valve, keep it as close to that as possible during the critical break-in to keep it cool.
IMO Pmags and angle valve engines aren't a great combination.