rke_011 Posted March 4, 2014 Report Posted March 4, 2014 Hey, Building a ke10 turbo.. It is currently on a 4k but have a 5k i will be building asap. The question I have is, the 4k has the standard 4k dizzy on it which has a coil with a resistor. The ke10 never had a resistor.. Can I run a non resistor type coil (gt40 type thing) with the 4k dizzy or are they built to match? would there be any benefit of swapping the dizzy over to a ke10 type? seems the girl is cranking but not starting and has very little to no spark.. once io get decent spark out of a coil ill worry about leads and things Quote
ke70dave Posted March 4, 2014 Report Posted March 4, 2014 As far as i understand you just need to match the coil with the resistor (or no resistor) The distributer shoudlnt care what coil it fires. Quote
Banjo Posted March 5, 2014 Report Posted March 5, 2014 There are a couple of types of 4K distributor. There is the stock standard "points type", and the reluctor sensor type. The reluctor type needs an external ignitor to switch the coil primary current. There is a 5K distributor, that has reluctor pick up & ignitor fitted inside the distributor itself. Pretty rare, but I've got 1 or 2 after searching a bit. Some guys don't like the 5K one, because of the advance curve it has (bit sluggish). Dare say, you could get the 5K dizzy recurved if you needed to. The simplest & most reliable arrangement is to get hold of a 4K "reluctor" distributor & buy an external ignitor off ebay for $20 - $30. The external ignitor will allow you to run a low impedance coil like the GT40. (ie: coils with low resistance primary coil) If you try and drive a low impedance/resistance coil with points distributor, you'll have very short life of the points. Points type distributors are only intended for standard impedance coils, with resistor in series, which is switched out (s/C) during starting, to make for easy starting. The ultimate way to go, beside a MegaSquirt / Haltech or the like, is to feed a 4K reluctor distributor, with the auto advance mechanism locked up, into a Jaycar programable ignitiom module & ignitor. With that you can adjust the advance curve to exactly what you require now with your 4K, and later when you upgrade to a 5K turbo. Cheers Banjo Quote
rke_011 Posted March 5, 2014 Author Report Posted March 5, 2014 (edited) if i get a photo of the dizzy could you identify it? or how do i know what it is.. its points and the dizzy cap is a shit load bigger than the original k.. does The reluctor type run points or electronic? have ordered msd 6btm to control boost timing so i don't think i have to lock it? i could be wrong.. Edited March 5, 2014 by rke_011 Quote
Kirill Posted March 5, 2014 Report Posted March 5, 2014 I have GT 40 coil with resistor hooked up to standard points dizzy (1979 4K). It works no problem. Quote
Banjo Posted March 5, 2014 Report Posted March 5, 2014 There are two types of coils. Those designed for use with "points type systems", which usually have primary coil resistances of several ohms. I think the GT40R is 3.4 ohms. Kirill, I think you are OK. Then there are coils designed for use with electronic ignitors, which switch the primary current. Their primary coil resistances are usually less than 1.0 ohm. 0.4 ohm is common. These should not be used with points type distributors. Even the Bosch website states this clearly in their FAQ section. Igition coils used with electronic ignitor systems usually don't have a series "ballast" resistor. The series ballast resistor is usually only fitted to coils for "points type" applications. The points type ignition coils are usually designed as say 9 volt coils, although they are labelled 12 volts. With the resistor in series whilst running, with alternator volts 13-14.4 volts, the resistor drops the applied voltage to the coil, to about say 9-10 volts. However when starting the car, and cranking in cold weather particularly, the battery voltage can commonly drop to 9 volts. During cranking, the "ballast" resistor is switched out, or short circuited, so the full battery voltage is applied to the 9Volt coil, and therefore producing maximum spark. Note the label on the bottom of the GT40R coil. To be used with resistor. Probably what the "R" on the end indicates. Cheers Banjo Quote
Taz_Rx Posted March 5, 2014 Report Posted March 5, 2014 if i get a photo of the dizzy could you identify it? or how do i know what it is.. its points and the dizzy cap is a shit load bigger than the original k.. does The reluctor type run points or electronic? have ordered msd 6btm to control boost timing so i don't think i have to lock it? i could be wrong.. Nah buddy, the btm negates the need to lock the dizzy. The stock mechanical advance works as per normal for off boost operation, then when you get boost the btm will retard as required...or set. Now with a 6a they also act as an igniter, so you could run an external igniter electronic dizzy and have the 6a do the job of the ex igniter. The thing I'm not sure about is weather your 6(no a)btm also does the job of an igniter. Some reading on the msd website should tell you that. Hmmmm, the guys are right in saying that a non-resistor setup will burn out the points quickly.... But what I'm just thinking is maybe the fact you have the msd in the system will mean you could run a full 12v (gt40) without quickly burning out the coils - the same way in which an igniter in an efi system grounds the charge so its not discharged through the ecu and blowing it up. Ie... Points trigger msd - msd discharges to ground and fires coil - mechanical advance does its thing and finally the btm part retards a required while on boost. Quote
rke_011 Posted March 6, 2014 Author Report Posted March 6, 2014 Got it started yesterday with no exhaust.. Sounded Luke a truck.. But it runs! Quote
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