R34 Gtr Coil Trigger Voltage ?

[XKLABA]

Does anyone know if the R34 GTR coils are 5v or 12v trigger ?

[XKLABA]

I thought for sure someone would know this, any chance someone with an R34 GTR can unplug a coil turn ignition on and read the 3 pins, when looking at the plug the center one is 0v-earth, I need to know the two out side ones, cheers

[Ben C34]

Pretty sure you cant measure it like you suggested as the trigger voltage is only applied for the dwell duration to excite the coil each fire (3ms). You would need an oscilliscope to measure it with the car running. You could easily figure out which one is the 12v supply with your suggestion though

Edited November 13, 2013 by superben

[XKLABA]

Ok, no, it has 5v constant feed and to fire the coil it drops the feed for a ms, I've have just been informed on the computers forum it is actually 5v same as the 32/33

I have checked them and I got 12v-0v-5v in that order, but one of the guys on the other forum suggested it might be 12v instead of 5v so I thought I would check on here

thanks for the reply anyway

[Ben C34]

Glad you got your answer! But what changes when you change the dwell ? Its my understanding, and i could be wrong, that the coil sparks when the trigger voltage is removed, surely what changes is how long the trigger current is applied for before being removed.

[XKLABA]

That's right, the coil has 12v going to it full time, and 5v as a trigger, when the 5v is dropped to 0v the coil fires

[Ben C34]

That's right, the coil has 12v going to it full time, and 5v as a trigger, when the 5v is dropped to 0v the coil fires

I get that. But the coil is only charged for a limited time (the dwell) How is that achieved ?

[XKLABA]

Easier for me if you read this, to hard while im using my phone, should explain it nicely

http://www.extraefi.co.uk/dwell.htm

[Ben C34]

That link shows what I am trying to say. That the trigger voltage isnt constantly applied, its only applied for the dwell time (approx 3ms) to charge the coil the the coil sparks when released. Hence the need to use a scope when running. I havent checked, but if with engine off and ignition on if you are getting trigger voltage to the coils that would be a bad thing and cook them, as they are charging for way too long.

[XKLABA]

ok now im on the laptop I can read it properly, yeah you are correct, I have always looked at it differently, so when you turn the IGN on the 5v feed is activated until you go to start the engine then it is dropped to 0v to fire coil then reactivated to "charge" for how ever long it needs to then dropped to 0v again to fire etc, I'm still looking at it from the coil dizzy craby days where the coil is always on and discharged when the dizzy makes contact with the points, your way would be more relevant to this situation

I was also asking for it to be checked before the engine is started, with just the IGN on, it is to check the settings on the new computer, but it looks like when someone left the key on overnight has killed the coils and battery, not me, fark