911 ST twin Plug Coil Placement , FIRE HAZARD?

[varacoustic]

Wanted to get some opinions from you guys on Twin PLug Coil placement . I am finishing my ST style build , 3.2 SS Twin PLug, JB Racing , Webers... . I have the coils currently mounted the rear of the engine bay like the photo below..



i do love this look ...Now I'm having a few friends warning me this is a horrible location , fire hazard , coils have to be as close to Dizzy , etc.
I obviuosly understand the logic but yet I see so many ST's and RSR builds current and vintage using this coil location. Thoughts?

[varacoustic]

[phelix]

What is the logic for that placement to be a fire hazard?!

[macssc911]

I made a aluminum bracket for mine

[varacoustic]

I think the reasoning was having the high voltage wire pass through anywhere near the carbs, nearer to anything fuel related .. The photos I've seen time and timer again of ST and RSR builds , vintage or newer you see the coils in the rear commonly , esp cares built in Europe . here in the states we commnly see two red boxes that say MSD and coild in all types of placed , fan housing or up the firewall area . I am trying to run a period looking setup with 2 6 pin CDI's and coils in the rear , but have been getting some pushback from a few pals and mechanics, I wonder why Porsche would do it this way if it was a problem?

[Raceboy]

[Mayra]

used as the first heat transfer surfaces after the furnace. Often a platen arrangement is preferred to create a fouling-resistant construction. Spacing in the first superheaters can be from 150 to 1000 mm.

[RobFrost]

Regardless of position, always carry a fire extinguisher.

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[stownsen914]

The coils are near the carbs no matter what you do, as are the sparkplug wires. In a well maintained car, I'm not understanding the fire hazard comment.

[RobFrost]

Originally Posted by stownsen914

The coils are near the carbs no matter what you do, as are the sparkplug wires. In a well maintained car, I'm not understanding the fire hazard comment.

Many 911s are lost to engine fires, for whatever reason. So always carry a fire extinguisher.

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[al lkosmal]

[Jonny H]

The firewall placement in itself isn't 'bad'. My criticism would be more to do with cable routing and length of cable. Ideally, the HT leads are as short as possible and in this case they are quite a bit longer than than side mounting. Resist the temptation to run the two king leads too close together to avoid cross firing.

Where are the CD boxes mounted? Assuming they are on the left side, then there is opportunity to keep their power and coil feeds away from the HT by running them to the back of the firewall and along to the coils. This is a good thing to minimise electrical noise affecting the boxes.

Believe it or not, I worked on a twin plug car with firewall mounted coils which misfired and kept destroying Bosch CDI boxes. The power, signal and coil wires had be neatly bundled together WITH THE HT LEADS!!! This is asking for trouble as the HT leads emit a huge amount of EMI which introduces voltage spikes onto the power and signal lines.