changed the coil to an aftermarket one and now it wont start

[sergei]

what is the reason you think that it will damage my ignitor/ coil?
is it bacause of the low primary resistance?
if so could i put a resistor in series before the coil to reduce the current draw?

can you please explain what you mean by a coil that will work with an inductive system?

Huge difference between CDI and IDI.
Putting resistor is counter productive, since the coil will not reach the energy levels without capacitor discharge driving it, and just heat up without making an useful spark.

CDI works by having a capactor that is charged to few hundred (400-600) volts rapidly discharging through coil, which causes a high voltage spike on the secondary. The CDI coil has lower primary to secondary turn ratio, smaller core as well as less turns, since it works on short high voltage pulses.

IDI works by directly driving the coil at ~14V and interrupting the current supply thus rapidly collapsing the field, which induces the high voltage in secondary. The IDI coil has greater primary to secondary turn ratio (since it is being driven by lower voltage) as well as higher number of turns in the primary and chunkier core.

In CDI the energy stored in capacitors while in IDI the energy is stored in coil itself.

[matt dunn]

CDI systems also create the spark through the sudden buildup of magnetic field in the coil,

where normal ignition the spark is created by the collapse of the magnetic field,

so the spark will jump the wrong direction too.

[tim_blair]

is there a difference in performance between the two?

[Rookie]

Not if you don't need it.

[mr30%jr]

off topic but have got the attention of some clever ppl like serg.
seen a few people with links running can coils, stock igniter and ballast resistor and also the same setup with a link igniter, this also seemed wrong.

so if you used a blacktop ignitor and an aftermarket coil a ballast resistor would be a waste of time right?

also with a link ignitor you would just set the dwell correctly for the coil correct?

[tim_blair]

Not if you don't need it.

this doesnt answer my question

[Grrrrrrr!]

Yes, there is a difference in performance.

CDI produces a very hot spark, but it doesn't last long. Hence why MSD type ignitions exist (MSD= Multiple Spark Discharge), they figure if the first one doesn't light it, the second one might.

Inductive isn't as hot, but lasts a lot longer, so has a greater time to ignite the mixture.

[QikStarlie]

yeh but, difference in spark performance doesn't mean difference in engine performance.

Not if you don't need it.

this doesnt answer my question

you dont need it.
basically if the mixture ignites, spark is good enough. you aren't going to gain power by firing a huge spark at the same mixture, that a weaker spark will ignite.

off topic but have got the attention of some clever ppl like serg.
seen a few people with links running can coils, stock igniter and ballast resistor and also the same setup with a link igniter, this also seemed wrong.

so if you used a blacktop ignitor and an aftermarket coil a ballast resistor would be a waste of time right?

also with a link ignitor you would just set the dwell correctly for the coil correct?

ballast is is just there for start up. when you cranking ballast is bypassed, so coils gets enough power when cranking, since theres a big volt drop when the engine is being cranked. once key is back to "on" it will be powered through the ballast.

link and the likes have dwell vs battery voltage so ballast is not required.

you wouldn't want to run a coil designed for a ballast setup with link

[sergei]

Toyota igniter is best to use with Toyota coil. The Toyota igniter does its own dwell control. The link igniters are simpler devices and can be used to drive various coils (where the dwell control is done by ECU).

In simpler terms the Toyota igniter is triggered by rising edge of the pulse and it disregards how long is the pulse, as it controls dwell by itself. Meanwhile the aftermarket igniter is armed by rising edge (where it supplies the coil with current) and triggered by falling edge of the pulse (where it disconnects the coil from current source, thus causing collapse in field). The length of the pulse determines the dwell time.(correct me if I am wrong here).

Using aftermarket coils with Toyota igniters is not the most optimal solution, as the toyota igniter is "tuned" for specific coil, and different coils need different dwell time.

BTW you don't need CDI unless you do >12000rpm (eg. motorbike) or have 24 cylinders with a single ignition coil (for whatever reasons).

[mr30%jr]

Toyota igniter is best to use with Toyota coil. The Toyota igniter does its own dwell control. The link igniters are simpler devices and can be used to drive various coils (where the dwell control is done by ECU).

In simpler terms the Toyota igniter is triggered by rising edge of the pulse and it disregards how long is the pulse, as it controls dwell by itself. Meanwhile the aftermarket igniter is armed by rising edge (where it supplies the coil with current) and triggered by falling edge of the pulse (where it disconnects the coil from current source, thus causing collapse in field). The length of the pulse determines the dwell time.(correct me if I am wrong here).

Using aftermarket coils with Toyota igniters is not the most optimal solution, as the toyota igniter is "tuned" for specific coil, and different coils need different dwell time.

BTW you don't need CDI unless you do >12000rpm (eg. motorbike) or have 24 cylinders with a single ignition coil (for whatever reasons).

you have filled in alot of gaps i had chuuuuur serg

[tim_blair]

by increasing the spark plug gap do you get a better burn of the mixture resulting in more power?

[matt dunn]

by increasing the spark plug gap do you get a better burn of the mixture resulting in more power?

No.