[TR] Ignition coil question..

Randall TR3driver at ca.rr.com
Sat Feb 5 21:19:39 MST 2011


> of a voltage higher than 8 VDC in a 12 volt system. The 
> writer stated that a resistor in series with the ignition 
> switch in the "ON" position will allow the full battery 
> voltage (usually slightly more than 12V) during start only. 

Just for clarity, some coils require the dropping resistor (aka ballast) and
some don't.  External resistors didn't become common until the early 70's,
so your TR4A would not have had one originally.  If you want to add one, you
need to change the coil for a type designed to use it.

On the side of the engine block might not be the best place to mount a coil,
but there is something to be said for keeping the high tension wire to the
distributor as short as possible and not forcing it to constantly flex as
the engine moves on it's mounts.  Anyway there must be some reason that
practically every car maker (with the notable exception of VW) mounted the
coil next to the distributor, right up until they did away with
distributors.  For years, GM even mounted it inside the distributor cap!

-- Randall  



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