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Tips
Tips

suggestions on Ignition coils

hondo402000

Darth Vader
Offline
I think I might have a coil problem, In purchasing a new coil, I was told I need a 3 Ohm coil, my car is a 71 TR6, no ballast resistor.
I would like to get a high performance type coil that is also epoxy filled, any suggestions?

Hondo
 
The 3 ohm part is right if you are running points or Pertronix with a non ballasted ignition; I know that for sure.
I just recently got a good deal on the Pertronix 3 ohm oil filled on Amazon. I noticed they also had epoxy filled for a few dollars more.
If you do end up sending your dizzy back to Jeff, reckon he'll make you a deal on a coil ?
 
The high-output coil will not benefit you unless you have moved away from points and are using an electronic ignition. With electronic ignition you can open the spark plug gap up and utilize the higher output of a performance coil. With points, the high-performance coil does little more than a factory coil.

For reliability and a "standard" coil I am a big fan of the Bosch Blue. However, following the advice on the web, I only buy Blue coils made in Brazil. For higher performance coils I would follow Poolboy's advice and buy one of the Flamethrower coils from Pertronix.
 
That is what I have and I have my plugs gap set at .030". That is the optimum for my car.
 
I am running a Bosch Blue coil in mine which I got from Advanced Distributors. Seems to be doing a fine job but time will tell....
 
Anthony, you will probably not outlive that Blue coil. I hope that you do, as they last a long time.
 
I was quite happy with the Pertronix coil on my otherwise-stock Stag. Bought one for the TR3 (from Amazon), but haven't installed it.

One of the problems with opening up the plug gap is that it puts extra stress on the cap, rotor & wires. Wires are easy to upgrade, but the cap & rotor aren't. And there was quite a rash of early rotor failures a few years back (although I haven't heard as much about that recently).
 
Just put a Pertronix oil filled in mine, and as poolboy I also got mine from Amazon ($32 including shipping).
Also, take Paul's advice and regap to .030".
 
ordered my pertronix coil yesterday, maybe I should change the plug wires too? they are 5 years old

Hondo
 
Randall, I agree with you. When I tried running at .035" there was much carbon tracking on the inside of the cap and rotor. I moved them back down to .030" and have found nothing after almost 1,100 miles.
 
7000 miles just on this engine in the past 10 months at 32..many thousand more on Ol Basil with Champion RN12YC at 35. I've had no problems that I can contribute plug gap.
As an aside, in order to determine if my rotor is still in phase,I followed Jeff Schlemmer's instructions and found it very difficult to identify the telltale scorch mark on the rotor.
 
My flamethrower burned out after just approx 600 miles. I' m going to give them a second chance and have ordered a replacement and a spare for the trunk just in case. I used Moss Europe this time so I have recourse if it fails again.
 
Note that the recall is for the epoxy coil, which isn't really suitable for the street anyway. The oil filled coils cool better, making them more suited for long term operation.
 
MDS Blaster II with no complants. I wouldn't put champion plugs in my lawnmower, but that's just me.
 
I too use the Champions in mine for over 35 years and have had no issue whatsoever with them. To each his own.
 
poolboy said:
found it very difficult to identify the telltale scorch mark on the rotor.

I am not familiar with what and where this scorch mark will be. Did Jeff say that too much plug gap will produce such a mark? Where exactly do you look for the mark?
 
coil arrived today going out to put it in and see if the missing goes away, I might put my MSD unit back in too, next will be my new linkage for my webers, Pics with that work

Hondo
 
dklawson said:
poolboy said:
found it very difficult to identify the telltale scorch mark on the rotor.

I am not familiar with what and where this scorch mark will be. Did Jeff say that too much plug gap will produce such a mark? Where exactly do you look for the mark?

The scorch mark I was looking for identifies the locations on the rotor "blade" where the spark arcs from the rotor blade to the spark plug wire contacts in the distributor cap. I was relating it to the spark plug gap only because the greater the plug gap the higher voltage the coil must develop; so I was just saying that the plug gap I'm using is not so destructive as to leave a very noticeable trace of carbon in that particular location.

About the "in phase" part of my comments, Jeff says that a good indication of the rotor being in phase with actual moment of ignition is if the scorch marks are found 1/4 to 1/3 of the way from the leading edge of the rotor blade. That should leave enough room on the blade for the timing to centrifugally advance. If you are out of phase the spark may have to arc across a greater air gap (possibly before the rotor and the plug wire contact line up) as the centrifugal advance increases. So much so and it may be a miss at higher rpms.
 
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