Triumph Repair: rough running when hot/under load, coil resistance, smooth as silk

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Thanks, I never removed the wires and besides, it only "stumbles" on acceleration. It appears to be a coincidence as I put everything back the way it was. I will replace the cap and rotor as that is the only reasonable explaination. ken

My '74 TR6 ran fine until I installed Pertronix electronic ignition module. It then ran very rough off idle. Thinking it was the module I then re-installed the points only to find out it ran just as poorly. Timing and dwell are fine, no loose vac hoses and the plugs look normal. Coil resistance is 1.8 ohms and voltage is good. What happened?    Ken
Answer -
Hi Ken, double ckeck things like the firing order. It sounds really like it has a crossed wire! also the cap or a wire is bad ( probably a wire ) while it's running take some insulated pliers and remove one wire at a time then put it back look for change or no change this will point you to the problem.sorry for short answer I've got to run but re- ask if this doesn't help and we will look some more.! Dave

Answer
The first GT6 I bought, which was over 25 years ago, had a stumble on acceleration. it was so much faster than my MGB that i didn't care! after a tune up it was smooth as silk. (it really needed sparkplugs). also check the fuel filter and or bad gas. I can't think of much more. if it was more serious it would be steady with no changing in the miss-fire. Dave