Electronic Ignition - Vacuum

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Andymoor94
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Electronic Ignition - Vacuum

Post by Andymoor94 »

Hi guys,

Now Eugene is running on his news carbs (and very well, may I say!) I am looking to upgrade to electronic ignition.

One thing I noticed is that my new carbs don't have a vacuum port for the dizzy advance, so I presume never had the advance on the car they came off. Normally, I'd be up in arms about this, but I've noticed an Accuspark electronic ignition dizzy appears to not have a port to receive vacuum anyway?

Is that right? Do they advance by themselves?
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Eugene - My daily driver
1954 4 Door Saloon with original 803cc Engine.
MCYorks
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Re: Electronic Ignition - Vacuum

Post by MCYorks »

Looking at the Accuspark website they seem to offer the both the Lucas 25D or 23D distributor for the Minor. The 23D doesn't have a vacuum advance but the 25D does. Both models will have centrifugal advance regardless.

The vacuum advance, if it's working properly, is supposed to improve economy and drivability under part throttle conditions, but the engine will run without it. I was under the impression that all the A-series engines fitted to the Minor had distributors with vacuum advance. Someone else on the forum may know different. If your engine is the 803cc then it's probably fitted with the Lucas DM2 distributor, which does have vacuum advance. So the 25D should be a straight swap.

If there was no extra cost involved I would go for the 25D, just to have the vacuum option if I ever changed the carb again. But it's personal preference.
kevin s
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Re: Electronic Ignition - Vacuum

Post by kevin s »

It will run fine without it, some cars never had vacuum advance like the lotus elan, you might lose a little on fuel economy but it certainly won't be the end of the world.
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