New igintion coil

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gsa60
Started learning about 480
Posts: 82
Joined: Tue May 21, 2013 10:18 pm

New igintion coil

Post by gsa60 » Sun Apr 17, 2016 3:33 pm

Hi guys,

I'm gonna buy a new ignition coil.
One doubt popped to mind. According to haynes, primary winding resistance is between 0.4 to 0.8 ohm.
I'm thinking of buying an oil filled one that has 3ohm. Is this resistance difference OK?
Thanks for the help.

Robou
Knows an Aerodeck isn't a 480
Posts: 258
Joined: Sun Jul 08, 2007 11:34 pm

Re: New igintion coil

Post by Robou » Sun Apr 17, 2016 6:39 pm

No. You will get a spark, but with considerable less energy. Stick to 0.4 Ohms.
Too old to bother
480 Turbo midst '91

gsa60
Started learning about 480
Posts: 82
Joined: Tue May 21, 2013 10:18 pm

Re: New igintion coil

Post by gsa60 » Sun Apr 17, 2016 7:29 pm

Thanks Robou for the help,

I was looking at one of those coils and although they had more primary resistance, since they were described as High-output (40kV), I was thinking that It would produce a stronger spark (perhaps higher secondary to primary winding ratio).

Any more specs I should be concerned with? like secondary resistance etc.?

Again, thanks for the help

Robou
Knows an Aerodeck isn't a 480
Posts: 258
Joined: Sun Jul 08, 2007 11:34 pm

Re: New igintion coil

Post by Robou » Sun Apr 17, 2016 8:42 pm

This description is pure nosense. The voltage drops the moment the spark jumps, which is at appr. 10.000 Volts, depending on the gap and the compression.
The only thing worth while to check is the impedance of the primary which is responsible for the rise time of the current. The lower the better. But, if you manage to find it in the specs, it is probably lied about and the coil is too expensive.
As embedded in my advice: Any coil with the right resistance will do. The ignition system is very basic and really nothing can be done to improve it, but replacing it by a standalone system.
Too old to bother
480 Turbo midst '91

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