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coil resistance .SP

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daimlersteve
Posts: 299
Joined: Wed Mar 09, 2016 11:20 am

coil resistance .SP

Post by daimlersteve » Sun Dec 23, 2018 5:18 am

org. spec. rqrd , thanks ,
steve

daimlersteve
Posts: 299
Joined: Wed Mar 09, 2016 11:20 am

Re: coil resistance .SP

Post by daimlersteve » Sun Dec 23, 2018 7:47 pm

Come on chaps, some one will have a spec -- 3.5 ?

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Vortex O'Plinth
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Joined: Fri Feb 12, 2016 8:15 pm
Location: Gloucestershire

Re: coil resistance .SP

Post by Vortex O'Plinth » Sun Dec 23, 2018 8:04 pm

The original coil was a Lucas HA12 Part No. 45102/F. I don't know the specification.

The modern replacement, Lucas DLB101, has a primary coil resistance of 3.0 Ohms.
Nick

Pas d'elle yeux Rhône que nous.

daimlersteve
Posts: 299
Joined: Wed Mar 09, 2016 11:20 am

Re: coil resistance .SP

Post by daimlersteve » Mon Dec 24, 2018 1:50 am

Good one , thanks boss .
PS., now have the 2.8 short block in my workshop. Will blueprint the heads to the block over the break.
( pistons stand proud of the face so the chambers may need dressing to give a 30 though interface across all cylinders . ) Cheers to all --- have a safe one.

Steve

daimlersteve
Posts: 299
Joined: Wed Mar 09, 2016 11:20 am

Re: coil resistance .SP

Post by daimlersteve » Sat Dec 29, 2018 12:41 am

Have tested four coils , old /new , A Lucas branded new reads 1.7 ohms, Lucas stamped 1964 - 3.5 ohms , Bosch gt 40 (2) 3.5, Crane for electronic pickup (2) 0.6 ohms. So there's a great variance between brand and application.
Have recently brought the third SP home from the paintshop and almost completed the reassembly of Chrome and fittings , lookin good in red with black interior .
regards, steve

Soundmike
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Joined: Thu Mar 17, 2016 8:54 am

Re: coil resistance .SP

Post by Soundmike » Sat Dec 29, 2018 3:05 am

Hi Steve. A standard 12volt coil should be 3 - 3.5 ohm primary. Current with points closed static about 3.5 amps. Low resistance coils only for use with ballasted ignition systems. ie fixed resistor in series with coil which is bypassed when starter engaged.
Regards and happy new year, Mike.

daimlersteve
Posts: 299
Joined: Wed Mar 09, 2016 11:20 am

Re: coil resistance .SP

Post by daimlersteve » Sat Dec 29, 2018 8:24 pm

Howdy Mike , How're things down there ?
As well as the resistor type application the electronic systems can also run .5 ohm coils . Follow Keith Humps tribulations in Dart Talk of late. I haven't tested his current (4th) coil as yet but asking for guidance across the counter at Repco is not recommended it would seem !
Which Sp are you planing on bringing to the Bun fight ?
steve

Soundmike
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Joined: Thu Mar 17, 2016 8:54 am

Re: coil resistance .SP

Post by Soundmike » Sun Dec 30, 2018 4:58 am

All well here! 0.5 ohms! At 12 volts, thats 24 amps! It must surely be a capacitor discharge system or have some form of current limiting. These used to be common in 2 stroke outboard motors, plugs had no need for earth electrode, enough voltage to spark to anywhere!!!! Coil for each plug, no distributor, always had to be careful not to leave HT leads disconnected as they would destroy anything within cooee. Very important when used in automotive systems as CDI's will destroy coils, dissy caps and rotors in the blink of an eye. I also wondered if the pick up sensor in Keith's setup was in the wrong position as he commented that the timing was radically different?? Maybe this put the the rotor was then in wrong position relative to cap contacts..... Could lead to strange thing to happen...
I will be taking black ex USA car, have made red one available should anyone have an oops.... Both going well. Cheers, Mike

daimlersteve
Posts: 299
Joined: Wed Mar 09, 2016 11:20 am

Re: coil resistance .SP

Post by daimlersteve » Sun Dec 30, 2018 8:08 am

The 0.5 ohms coil ign unit used to be Crane Cams sideline ,now on- sold and called " Fast "but still usa made it seems . good spark ,can make you jump a tad . Its recommended the feed be direct ( via a relay) from the battery with the ign switch activating the relay , though i havent done that as yet. Hopefully the cap lasts the distance. Have done a few thousand on it so far.
Years ago i was sorting a gt6 with 2'5 ltr. power. the owner supplied an optical sensor and MSD 6 al pack. The better the spark the worse it ran. Close examination of the dizzy setup showed the design flaw .-- With the supplied conversion pack installed, the unit fired when the rotor was midway between the HT contacts . The increased spark was jumping back and forth as the revs climbed . Crap design .
The Crane setup is supplied with a collection of universal mounting brackets so it can be made to fire wherever the rotor needs to be pointing --- a trap for young players who dont really understand how these things work.

cheers.
steve

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