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TR6 Timing the 72 TR6?

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72TRLVR

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I am new to the site, but I have been a long time TR6 owner. I recently installed a Pertronix electronic ignition. The installing part was easy, but she is not running the same as she was before the change. She starts easily and I can drive without any problems, but seems to lack power on acceleration? I normally have a mechanic do this, but I got myself a timing light and I would like to learn to do it myself. I have had this car since 1987 and it has been a dream to drive and other than having the clutch replaced recently, she has always run great. If anyone can steer me in the right direction, I would be most appreciative!!

Thanks, Cline (72TRLVR)
 
That's common. And from what I've seen it's simply because the pick-up for the Pertronix does not sit in the exact same spot (rotationally speaking) as the points did in relation to the lobes of the distributor shaft.
So far it seems that a slight rotation of the dizzy in the clockwise (advance) direction will bring the pickup back to the timing that you had prior to the conversion.. Give it a try; as long as the tach cable is connected you can hardly over advance the timing.
Personally, I'd see if you could exchange the timing light for a Vacuum Gauge if you really want to find your sweet spot..
Those timing marks on the damper have lost their significance due to stretching of the timing chain, wear in the chain sprockets, wear in the dizzy drive gears. I could go on, but a Vacuum Gauge is invaluable and more accurate unless the engine is virtually new. With the Vacuum Gauge you'll probably be at the recommended Degrees of timing although the damper marks probably won't reflect it due to the wear of the components I previously mentioned.
https://automotivemileposts.com/garage/v2n8.html
 
Thanks for the tips poolboy! I'll give that a try. What you said about the position makes since and I am partly happy to say that when I tried to tune it by ear, I turned the dist clockwise and made a positive improvement. Also, thanks for the site info! I'll post again when I get a better result.
 
One comment, if you are going "by the book"; the books are frequently misleading or simply wrong. You'll find two timing specifications for US models, generally "dynamic" timing is given as 4 degrees after top dead center (ATDC) and "static" as 10 or 12 BTDC; and it will typically say to disconnect the vacuum advance.

But starting in 1972, US-spec TR6 did not have vacuum <span style="font-weight: bold">advance</span>, and the 4 ATDC figure is with the vacuum <span style="font-weight: bold">retard </span>connected and operating (not broken or disabled by the thermal switch in the upper radiator hose or radiator). If your retard is not working for whatever reason, then you should use the 'static' value. Otherwise you will get exactly the symptom you describe, sluggish performance (and high fuel consumption).
 
+1 on the Vac Gauge

Cheers,
M. Pied Lourd
 
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