I'm rewiring my car and want to move my coil(and resistor) to my firewall but would have to mount it horizontal. I'm hearing mixed opinions on the subject. Anyone have any knowledge or experience doing this with a mallory promaster coil (#29440 circa 1992)?

Current location:


Location I want to remount it to:

 

do it

 

Anyone else have any input on this? The instructions (circa 1992) says "it can be mounted at any angle". But when I call Mallory, which is now hooker/MSD/Accel/etc...a guy with an accent tells me "sir, we recommend you mount it vertically".

 

This should apply to your coil (latest and greatest from 2016):

https://www.jegs.com/i/Mallory/650/29440/10002/-1
(Scroll down and look at the Instructions)

MOUNTING PROCEDURE
Ignition coils should be mounted on a flat surface as close as possible to the distributor and away from extreme heat from engine components. DO NOT mount ignition coils to the engine.

Step 1: PROMASTER® Ignition Coils may be mounted at any angle. Find a suitable flat surface to mount the ignition coil.

Step 2: Center punch the mounting pattern using the ignition coil bracket as a template to mark locations for drilling holes. Drill holes using a 9/64" drill bit.

Step 3: Mount the ignition coil bracket using three #10 x 3/4" screws.

Step 4: Slide the ignition coil into the ignition coil bracket. Mount the ignition coil in the ignition coil bracket with the #10 x 1" screw

 

Thanks Paulo.
That's what the instructions that came with it say also. However, their 'tech' guy says otherwise. I'd like to hear from others whom have mounted it in that location and/or sideways, i.e. the high-voltage terminal on the bottom.

 

Of these two positions, which one would be better?
I'm a bit concerned about how close the high-voltage terminal is to a ground surface in the upright position and the heat from the exhaust(and the possibility of the oil not covering the internals) if in the horizontal position...

 

Has anyone had issues with their coil output/high voltage terminal being within 1 inch of a grounded surface?

 

The coil secondary will not arc across an are gap of one inch. A rough calculation using the following formula:

Voltage required to jump air gap = air gap (cm) * 30,000

Voltage required to jump air gap = 2.54 (cm) * 30,000
Voltage required to jump air gap = 76,200 volts

Mallory's specs for the coil is 49,000 volts max. Remember that coils only put out enough voltage to jump an air gap and that electricity takes the path of least resistance. A 1" air gap is a huge resistor.

 

Thanks Paulo! My coil will jump almost 2" where it's currently mounted if I take the coil wire off and crank the engine.