ignition coils

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Is there an easy way to check if a coil is to be used for a cdi or inductive system. I was sure that cdi coils had lower resistance (0.3 ohms) compared to about 1 ohm for an inductive coil.

Anybody know of any COP that will handle 100mJ of energy from a cdi. We were previously using COP from a GSXR600 97 model, but they overheat at 100mJ causing failure.

Thanks

Will Attard

[powered by wattard]

Is there an easy way to check if a coil is to be used for a cdi or inductive system. I was sure that cdi coils had lower resistance (0.3 ohms) compared to about 1 ohm for an inductive coil.

Anybody know of any COP that will handle 100mJ of energy from a cdi. We were previously using COP from a GSXR600 97 model, but they overheat at 100mJ causing failure.

Thanks

Will Attard

[BryanH]

Will, a cdi coil is designed for low capacitance. The resistance is irrelevant.
In Sam Newman speak, a CDI coil has less and fatter windings, and a low turns ratio.(because the primary voltage is 30X higher)
IMO bike cops are not suitable for boostd engines. Have a look at the mercury CDI mini coil that Motec stock. Use it with a short spiral wire ign lead. Bolt it to the engine. VI
Bryan H
The more I learn,the more I realize how little I actually knew

[Mark Peugeot]

While it may be a slight weight penalty, those big nasty GM coils pack quite a punch. Plus it's neat to watch them arc from tower to tower in a waste spark configuration. They are also cheap at about $30 US each.

I'm no engineer, but I do know that with a CDI these coils make a nice hot spark. Which is what you want on a boosted motor.

Mark
UTSA FSAE- (Dammit Jim, I'm not an Engineer, I'm a Psychology Major.)

[Angry Joe]

Be careful with those GM coils, we tried them and they saturated at 11,000 rpm. We used Accel motorcycle coils (non-CDI), which worked great past 15,000 rpm, but I can't comment on forced induction applications.

[Mark Peugeot]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Angry Joe:
Be careful with those GM coils, we tried them and they saturated at 11,000 rpm. We used Accel motorcycle coils (non-CDI), which worked great past 15,000 rpm, but I can't comment on forced induction applications. <HR></BLOCKQUOTE>

Ahhh the curse of working with 9000 RPM rev limits too long. Thanks... I would have had to learn the hard way otherwise!

I guess it's back to the drawing board.

Mark