Ignition Systems

[Token]

G'day all,

 

So The 'Rolla (Ke30) has a habit of blowing coils. Its just gone through it's third, none of them terribly good (bosch gt40r, gt40t, gt40rt) but they we're what I had lying around the house, and they got the job done.

 

I believe it is linked to the "electronic" ignition (optical type points replacement) and the fact it has a larger dwell time then points, causing the coils to heat up and die, but I really don't know, i just replace the things.

 

So my question is this, if I go out and grab an MSD blaster 2 or equivalent, will it handle the extended dwell times better, or am I just going to blow it in 6 months and effectively waste $60. The Ignition unit requires a primary resistance of 3ohms, so any electronic coil will have to be ballasted.

 

Also whilst on the topic, will HEI systems slow down the spark degregation at high RPM, or do they just provide a more powerful spark across the range, but still require an equivalent amount of time to charge?

 

I understand CDI is probably the way to go, but I don't have a spare $500 floating around, and even if I did, I'd probably just spend it on beer and hookers.

 

Cheers,

 

Token

[GJM85]

I understand CDI is probably the way to go, but I don't have a spare $500 floating around, and even if I did, I'd probably just spend it on beer and hookers.

 

You mean a CDI like this one I recently removed from my ke20?

 

[rian]

Its just gone through it's third, none of them terribly good (bosch gt40r, gt40t, gt40rt)

These are all different voltage coils? GT40T coils are 12v, GT40R and GT40RT are 6v/9v(one or the other, I can't remember?)

 

And I thought the GT40 and GT40T were both 3ohm coils and the GT40R and GT40RT were 1.5ohm coils?

 

I've been running a GT40, the oil filled type, with an electronic distributor for ages without any problems.

Though I've heard the GT40T, the resin filled type, can be unreliable. Just what I've heard, I've never actually used one.

Edited April 25, 2012 by rian

[Token]

Alrighty, I have no idea how to quote shit so you can figure out what applies to who.

 

I am aware all the coils I mentioned are 'different' voltage coils, but wired up correctly, it didn't seem to affect performance at all. (you just ballast the Gt40r/rt which effectively makes them 9v coils whilst running)

 

I have heard that the transistor type coils are not the greatest, (mini guys hate them) but they were cheap (free - i had them in the shed) and they did the job. However, they just don't seem to last and I have it in my head (read/been informed at some point) that its potentially due to the extended dwell times (at idle) causing the coil to overheat.

 

GMJ85,

your spruiking the CDI? How much? and why was it removed? But yes, thats pretty much what i was referring too.

[styler]

Yeah electronic iginition systems from factory usually has adjustable dwell,

but some of those aftermarket pickups don't at all they just send the signal.

 

Theres ballast and non ballast systems as mentioned and need the setup to suit.

 

Expoxy coils are only for high vibration enviroments, oil filled has much better cooling.

 

CDI has short duration high intensity spark and actually needs to multispark to get a good

burn time especially at lower rpms.

 

Have you measured dwell with a multimeter, could be a good idea to see what's going on.

[GJM85]

I was using this CDI on my KE20. GT40 coil, 3k points dizzy with adjustable dwell. I've had no problems with the unit. I removed it because I was having a charging problem my car and coulkdn't work it out and removing the CDI I though might have fixed it. It turned out to be the alternator regulator and I haven't been bothered to put it back in.

 

It still works fine. Heaps easier starting and an even idle. Didn't notice a great deal of difference in the performace department. For some strange reason it even prolonged the lift of my breaker points in the dizzy.

http://www.street-fi...diignition.html

 

If your really really keen on it I may part with it for 12,000cents (120$) ;)

Edited April 25, 2012 by GJM85

[Token]

Alrighty, so i thieved a coil from my housemates '86 Track car, and it works sweet, so I'll run that till my MSD gets here (GMJ85, thanks for the offer, but I actually have a mate coming back from the US in a few weeks, and I've arranged with him to bring me back some goodies, inclusive a CDI).

 

How does one go about checking the dwell time with a multimeter?

 

I think my best bet is going to be install the CDI and change to a hall-effect type points replacement to give it a signal. Mainly looking at the CDI because from what I've read, they don't have the problem of spark breakdown at higher RPM. The car's a Khana car, so it see's a fair bit of abuse.

[snot35]

Nice, another khana car, have you put something in My Rides? :)