Ignition Curve

Post any technical questions or queries here.
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gs.davies
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Re: Ignition Curve

Post by gs.davies »

Hmmm. This is getting interesting. Built in a 23D4 housing. Wouldn't too out of place with a side exit cap and old style wires. I presume the vacuum from the carbs routes into a MAP sensor and there's no doubt that a modern ignition incorporating A rev limiter, an immobiliser and electronic reliability is a good idea. Stash the brain somewhere behind the dash liner and we could be in business.

And it's good enough for Swiftune..

http://www.swiftune.com/Product/1091/sw ... s-23d.aspx
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Re: Ignition Curve

Post by ianh1968 »

gs.davies wrote:Stash the brain somewhere behind the dash liner and we could be in business.
I don't think it has a separate "brain",
it's more than likely all inside the main distributor body, as per the 123...
... which is also available in positive earth...

Unless you are looking at this:
http://www.aldonamethyst.co.uk/

The story goes like this...
Many years ago, on one of my first trips to Aldon Automotive's dyno, they let
slip that they were developing a programmable distributor that would be integral
with a standard Lucas type housing. They asked me if I would be interested in
being a test-mule, to which I of course said "Yes".

Over the next few years, I regularly contacted them to find out the progress,
rather like a small child in the back of a car asking "Daaaad, are we there yet?"...

Unfortunately the answer was always "No", and eventually I got bored with asking
them. Investigation of what was available at the time lead me in the 123ignition
direction, especially as they offered a fully programmable version.

The CSI distributors were also coming out and were more "authentic" in that
they were at least "Lucas" based (Is that a good thing?)... Sadly when I was
looking, there was no programmable CSI, Aldon were still stalling, and I ended
up buying one, then another 123/tunes.

Finally, Aldon have released their "Amethyst" box, but the others have beaten
them at their own game and done the job within the main dizzy housing.

Each of these options has good and bad points - If I was starting from fresh now,
I'd probably use a fully programmable CSI if it does definitely exist. With this, I'd
use a "Distributor Doctor" red rotor arm as the standard "Genuine Lucas" ones are
proving to be basically sh!t and not fit for purpose.

I've had the opposite experience of Spider... If I'd have used a 123/Mini,
none of the curves would have supplied _enough _ advance.

Both the Aldon Yellow and Red distributors max out at 36 degrees total advance.
(or at least, should be installed so that they DO max out at 36 degrees)

My own engine, when 1380cc, also ended up with 36 degrees - 37 degrees was too
much and scrambled the power curve... There is much more to distributor advance
curves than meets the eye and even a minor spec change can completely mess
things up and make a curve totally invalid. Even something as trivial as a 10
degree increase in water temperature...

Ian
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Re: Ignition Curve

Post by gs.davies »

Ah, bugger. So this is no use for an authentic looking 850 then. I'd need a vac advance I think. The only other option is the 43d and that doesn't have a vac advance either.
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Re: Ignition Curve

Post by Spider »

This one I recent bought for a friend's build;-

Image

It has the Immobilizer but otherwise, as Ian said, there's no separate 'Brain' it's all inbuilt in the dissy. These ARE available in positive earth.
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Re: Ignition Curve

Post by gs.davies »

That's more like it. A 25D. Do you know if they're available with the screw on vac pipe type advance?

Where does the immobiliser bit go? Inside the car somewhere? I presume if I sort this prior to the electrical work starting on my car I could have auto sparks customise the loom so this looks like a factory install?
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Re: Ignition Curve

Post by gs.davies »

And I wonder if it's possible to get the serial number and date code restamped to match the original..?
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Re: Ignition Curve

Post by Spider »

Yes they do, the one you want is part no. CSI-MI-PO-13, 25D4 Body, Positive Earth, Vacuum Advance.

I don't think they'll stamp the body for you, but they do come blank, so you can stamp away.

http://www.csi-ignition.nl/en/home.html
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