I'm trying to figure out how to set dynamic timing on a 74
TR6...
(1) Underhood decal says 4 degrees ATDC, idle speed 850
RPM. Doesn't say anything about disconnecting vacuum retard
hose before setting timing though.
(2) Bentley reprint of factory workshop manual says to
disconnect vacuum retard and to then set timing at specified
idle speed (850 RPM in this case).
(3) On the previous page, it says vacuum retard can be
tested by removing vacuum retard hose from distributor and
idle speed should jump up 500 RPM or so.
See the problem? If I disconnect the vacuum retard, the
idle speed jumps to about1300 RPM but I'm supposed to time
it at 850 RPM.... Any suggestions? I'm guessing I should
ignore the factory manual's instruction to disconnect the
retard.
The reason this all comes up is because I just installed an
Allison electronic ignition. Unlike the Lumenition kits
I've installed, the Allison/Crane Cams is a "universal" kit.
That means there's an extra degree of freedom to setting the
timing up---the slotted disk/photodiodes can mount almost
anywhere inside the distributor. I like the Lumenition kits
better, thank you very much.
jim
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