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Section : Ignition and Distributers
Posted By : Stephen Airey, 17-Aug-2004, 07:11am
I see in the Moss catalogue that they sell a spring set for the Lucas distributor for the 1500 to change the ignition advance curve. However I cannot find
information on what it changes it to! Has anyone any experience/ knowledge of this? I am trying to decide if I need it as the final part of my engine
tuning.
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Posted By : Keith Dandridge, 17-Aug-2004,
10:43am
Can't help being a bit skeptical about any 'one curve suits all' fix. I woould have thought it far better to stay standard until you really know what
your specific engine needs. Then you can start playing with springs and altered base plates on a 'one mod at a time' basis.
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Posted By : Charles Bushell,
17-Aug-2004, 07:53pm
I bought a similar kit - it's basically a bag of different springs to play with. I don't have the experience (or a rolling road!) to set it up so
in the end I threw the kit in my spares box & sent the dizzy to Aldon Automotive for them to modify it for me. I think it was about
£40.
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Posted By : Andy Vowell,
17-Aug-2004, 10:26pm
I raced for years on a std 1500 lucas dizzy (with electronic ign) on a 1300 and found the advance to work fine (no vacuum). Only went to mapped
ignition when the combination of 4 into 1 exhaust plus very hot cam gave me a dip in power at 3-4000 rpm. but once past the dip it worked
fine.
Andy
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Posted By : Stephen Airey,
18-Aug-2004, 07:12pm
Why did you get rid of the vacuum advance? Is this a normal thing to do for a tuned engine. I keep getting the feeling I should have more
advance at idle (below 2000 it runs much better with around 12-14 deg advance but needs 8 deg static advance to not get detonation at high
rpm.
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Posted By : Jonathan
Binnington, 18-Aug-2004, 09:18pm
"I keep getting the feeling I should have more advance at idle (below 2000 it runs much better with around 12-14 deg advance but needs
8 deg static advance to not get detonation at high rpm"
that's interesting, what that sys to me is that either your engine needs a narrower range of total ign advance (12-14 btdc for good low
speed response) and less than the total advance at high speed (8 degs plus whatever the centrifugal advance gives) OR you have a dizzy
with the wrong amount of centrifugal advance (too much)
something you could consider is establishing the total amount of advance the engine will take without detonation (should be in the
region of 30-34 degs BTDC and then the advance needed for a lively engine at lower speeds and adju8st the dizzy centrifugakl mech to
give only just enough advance at high speed when set to the approropriate low speed static stetting. Then you get to mess with the
springs to control the rate of adbance with engine speed...