That is basically what Jaguar did for the later Series III V12 saloons. You're looking for a coil with a primary resistance of about 0.5 ohms. The coil on the V12 saloons is located near the throttle pedestal.

 

Ben,

I used a FuelMiser CC215 "Universal Electronic Ignition" coil on all of them, never had issues. Down here, back then, $45. That brand and number probably means squat up Norht, and remember I did all mine before the WWW was popular enough to be helpful. Did not have a home computer at the time.

The USA got SO MUCH stuff that restricts so much more stuff, that they are really up against it sometimes. They also got the 11.5:1 engine, we all got the 12.5:1 beast.

 

keep in mind it only is cooled when there is a lot of air flowing through it. Idle and residential driving it is probably closer to coolant temperature.

 

Not quite. Air intake temps do get close to 70C in idle conditions, but drop quite quickly when moving.

Relocating the amp above the rad exposes it to all the heat rising off the radiator and when the car is stationary absolutely no air moving over it either. The intake manifold does have air going through it whenever the engine is running, so there is always a cooling effect, sometimes greater than others.

 

We are recommending relocating the amp to a place in front of the rad, not above it.

 

If you put that amp on the radiator support TOP panel and shut the bonnet, there will be 2 nice neat dents in that bonnet, I did that, lack of beer was my excuse.

Out on the Horizontal panel IN FRONT of the radiator pack is COOL, and there is more than enough ambient air floating around when in traffic to satisfy its needs.

If you have the OE air cleaner covers, where the snorkel is pointing AT the radiator, and or fan, that air it HOT, no matter what you are doing.

If I could find a suitable LONG HT lead, of GOOD or BETTER, quality, the Ign Coil would go out there to keep that Amp company.

Engine bays are just to damn hot, with the emissions these older spec engines are forced to meet.

I recently replaced the Coil Pack Loom on the AJ16, in the X300. It was crispy and cracked at the rear of the cylinder head, and looked exactly like it had come from a V12 hangout.

Nothing changed in the Auto electrickery world. 20 years tops, and after that, you are simply on borrowed time.

 

I experienced this first hand. XJ12: when the tach hit 3500, it shut off like a light switch. New single coil: red line!

Good luck,
Rob

 

where were you measuring that temperature?

 

It comes from a write up done by a Jaguar Emissions Engineer, I have not measured it myself

 

That makes more sense, I thought I was beside the receiver dryer for the AC, which is a hot location.