Does anyone have a OEM Jaguar single coil? DAC6093. Or does anyone know the specs for this coil?

I'm trying to decide on ordering this Jaguar coil ( I found a NOS cheap ) or a higher voltage Pertronix coil. I'd love to know the ohms of the OEM part to look up the right alternate part.

 

JigJag, from what I can find in the ROM, the OEM coil should have 0.8 to 1.0 ohm between the + and - terminals at 20 celcius. pg 218, sec 86-14.


Have no information on the DAC6093 other than it replaces both coils.

Hope this helps somewhat
Johnny

 

Any coil with around a 0.5 ohm primary will work. Don't get hung up on voltage, as it's often irrelevant. If it takes 9,000 volts to fire the plug, that's where it will fire, having a 50,000V coil will make no difference, it will still make the spark at 9,000V.

 

You need to be careful replacing a coil (on a stock car) with an aftermarket.

Coil primary resistance (R) is only 1 parameter, the number of turns on the primary is also important as this governs the inductance (L) and both of these determine the time constant, how fast the coil charges "charge time = L/R". In car terms this is called the dwell time. If you get it badly wrong 1 of 2 things could happen the coil will go up in smoke or fail prematurely or the car will not rev.

If I were you I would take the tried and tested route of replacing the coil with one from a Marelli car DAC4608 these are available for under $100.00.

 

My intention is to enable a slightly larger gap while ensuring a fat, hot spark even at high RPMs.

 

FWIW, the DAC6093 coil IS a tried and tested (and Jaguar recommended) route for the Lucas ignition cars.

Is the 4608 a better choice? (I'm asking, not arguing)



Cheers
DD

 

Thanks for the explanation! I understand that the Jag coils are a safe bet and will work just fine. But the cost for a modern, alluminum heat sink mounted high voltage coil is the same. if I can find a superior part I'd like to.

 

I think you will wasting money. Norman who is building my engine has built a few V12 for racing and I know he used stock Jaguar coils, he also used Mercury V6 2 stroke coils.

Although this was in pre-HE and as CR rises and swirl increases spark becomes more of an issue.

You can use any coil, if you do you need to know its primary resistance and inductance. You can add a resistor to the primary coil to adjust the dwell time. The coil will run hottest at LOW RPM. Idle is where you need to set the dwell.

Here is a good article that explains Dwell.

Ignition Coil Dwell Calibration

 

The 4608 might be a better choice because I know it is made by a bunch of 'quality' aftermarket suppliers e.g Marelli, NGK etc. It's used on a bunch of non-Jaguar cars IIRC so lots of OEM-grade aftermarket suppliers make it.
Not sure if it's the same case with the 6093 - has anyone for example checked the NGK catalogue to see if they have a cross reference for it?