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Triumph TR6 - Ignition timing and SU carbs
I have a 1974 TR6, it was converted from PI to twin SU carbs. Any idea what the ignition timing should be please?
I've the same set up, I normally just advance the timing till the engine pinks under load then retard it slightly, the book settings don't really mean much nowadays because the composition of modern petrol is different from the '70s.
Next time I'm running it I'll take a strobe reading and post it here, if it will help you.
I also have the same set-up. Mine runs fine with a 10 to 12 degrees advance.
I disconnected the retard vacuum system and blocked the related hole in the inlet manifold.
i thought you needed the advance/retard mechanism or it hinders performance/fuel efficiency?
Or is it different with an SU setup?
There were various distributors fitted to the TR6, but basically the distributor fitted to a PI model did not have the vac advance or retard connected by the makers even if the unit is present. If you have an ex USA distributor fitted with vac retard only disconnect that, it was only an emmissions device and they run better without it.
Mine has a '73 PI distributor with a vac advance capsule not connected, some of the earlier PI distributors had both a vac advance and vac retard capsule!!
|Thanks for the info. I'll try it with/without and see how it feels. One other question. My breather pipe just exits the rocker cover and exits at the base of the engine...My SUs don't have a breather pipe inlet. Does this matter that they're not connected or should it be recirculated? Does it harm performance or running?|
I made an adapter and routed the breather back to the air filter, it won't affect the performance of the engine venting it to atmosphere, but it isn't very environmentally friendly, you could route it to a catch bottle if you dont want to use the filter casing.
If you aren't already a member it would be well worth your while joining the TR Register in the UK, they have a good forum and special deals on insurance etc.
This thread was discussed between 15/02/2005 and 16/02/2005
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