[TR] Ignition question (and hello!)

[Malcolm]

Hello list,

It's been a very long time since I have sent a message to the team.net list
Triumph.  Some of you may remember me!

Anyway, I have now got enough time on my hands to tinker again with my 1962
TR4.  Also, this year it is fifty years old, so I feel somewhat obligated
to pay attention to it.  I've got a bunch of new parts on it now, including
a stainless exhaust and new tacho/speedo cables, and have been trying to
get it to run properly.

I have fairly bad backfiring (through the carbs) under load when
accelerating.  I have balanced the carb inlets, the mixture seems OK, and
I've done the static timing.  I have new air filters (K&N) on order.  I
suspect that this is an ignition problem, though, and the Haynes manual is
dismal when it comes to troubleshooting the distributor.  Nearly every test
involves "compare your stuff with new parts, and replace them if they are
worn out".

My big question is: how much should I be able to rotate the distributor
rotor?  A little?  A lot?  15 degrees?  30?  Should it snap back to a
position at rest or just flop around?  I am trying to tell if the
centrifugal advance springs need replacement.

Will the K&N filters require me to fiddle with the timing?  They are
56-9327: http://www.knfilters.com/search/product.aspx?prod=56-9327

Has anyone got glowing recommendations, or horror stories, for electronic
ignition?  I've been scouring the Web and so far have not found a clear
winner.  I could rebuild the points (a la Distributor Doctor, or Advanced
Distributors) - or get Petronix, Hot-Spark, or some other drop-in
electronic replacement.

I am not building a concours car.  I want it to be reliable, running on
pump gas, with minimal roadside surprises.

Thanks!
-Malcolm