Performance affected by coil resistance?

[deejaycee_2000]

Does anyone know how it would affect your engine's performance if you have 1 different coil on a 3 cylinder 50hp yamaha, for instance if 1 of the 3 coils was a higher resistance coil than the other 2?

 

[Paul Moir]

Re: Performance affected by coil resistance?

Knowing the electronics, I highly doubt it.

If anything would be significant it would be the impedance rather than resistance. Unless the coil was defective somehow.

For example, the HV side of a J/E magneto ignition coil varies between 3.7k and 7.0k depending on the manufacture. No changes affect performance although I suspect some make for easier starting. At least it seems that way.

 

[deejaycee_2000]

Re: Performance affected by coil resistance?

Thanx Paul, I would have thought it will cause a different spark on the plugs ....

 

[Texasmark]

Re: Performance affected by coil resistance?

Energy in the coil = 1/2 L(I squared). Where L is the inductance of the coil in henrys and I is the current flowing through it in amperes at the time of interruption....EE handbook for as long as McGraw-Hill has been publishing such things (at least 45 years that I know of.....beins mine is copyrighted in 1961).

The energy is what blasts across the gap and ignites the fuel. So, if you have a different coil on one it will have a different energy content, but that may not be all bad as you may have more than you need and more than you need is just wasted energy........but if it's less than you need, then you have a missing problem.

Mark

 

[deejaycee_2000]

Re: Performance affected by coil resistance?

Makes sense now, thanx Mark