Aldon Amethyst - mapped ignition
Turbo Mini Forums

My car uses an Accuspark kit to replace the points (in an A+ mechanical dizzy originally out of a 1.0 Metro) - works fine with my Microdynamics box, and looks like it should be fine for triggering Amethyst.
One thing to bear in mind if keeping points with an elecctronic ignition, is that although the low current means there is no arcing & pitting, there is still wear of the cam follower (which will cause the points gap to close). Also, many of the Lucas dizzies have the connection to the points through a lead which is integrated with the condensor - these break down with the movement of the vac advance spinning the base plate to & fro, so neither the points nor condensor will last forever. Granted, with Amethyst the base plate will be locked down, so the life will be longer.
I found the Accuspark gave me a much smoother idle & running (probably from consistent timing), as well as immunity from points failure - with the baseplate locked, the final weakness of the leads flexing will go too.

1971 Austin (Healey) Sprite - running turbocharged since 1993
My Car thread: http://www.turbominis.co.uk/forums/index.php?p=vt&tid=448825

I think I will stick to Megajolt - at least I have positive experience of that system and Amethyst is still something of an unknown quantity.

It might take me a bit longer, but, as long as I leave the distributor drive shaft in (with my dummy distributor body on the end to stop it destroying itself) I will be able to drop a points distributor in there if the MJ gives any problems.

Anyone running this on here?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

this is just based on our experiance, Robert. There is a rule of thumb floating around that is 1 deg retard for every 1psi of boost. Obviously at some point this becomes impractical. Maybe our 10psi advance is very conservative and the rest of the boost is just catching up with it.

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

Sorry to be dense but could someone explain in simple terms how it advances etc? If the mechanical part is locked and the vac disconnected what does it alter?
thanks

mine: http://www.turbominis.co.uk/forums/index.php?p=vt&tid=570945

There's a box of tricks you get with it that advances to what ever you set it to. It links to your coil.

Edited by HUBBA.HUBBA on 25th Sep, 2014.

I realise the box fires the signal or what ever but the rotor arm still has to be in contact with the point if that is what it is called. So I guess it works within the range of contact area on the rotor arm like the photos below?

mine: http://www.turbominis.co.uk/forums/index.php?p=vt&tid=570945

You lock the dizzy and when you link up your amethyst you calibrate it using the led on the box of tricks( abit like the normal way of setting up ignition timing but finding tdc and turning dizzy housing) or just us ditch your points and go electonic ing

So any more news on this. ? Was reading this as my wife reads 50 shades but the end of this story is like starwors... it just ends when it gets Intresting. .. 😕😀

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Iam running this with good results Iam happy up to now

Finally got an Amethyst - still boxed from someone who struggled to follow the installation instructions...
Anyway, to answer a couple of questions from many months ago - the Amethyst can be triggered by almost any sensor - so points, hall effect, optical etc. It works out the firing interval and then anticipates when the spark should happen - so the a given spark is really triggered not by the switching event you would expect, but by the one before it. As for concerns over loss of accuracy from using the distributor for triggering - well yes, there is that. Having the facility to use the dizzy makes installation easy, but I can't see why it can't be triggered from a crank sensor - just use a trigger wheel with two notches 180 degrees apart, which will have the same effect as a four cylinder dizzy in terms of timing. The dizzy just needs to be somewhere near the right position to ensure the rotor arm aligns with the HT contacts in the cap at about the right time!

1971 Austin (Healey) Sprite - running turbocharged since 1993
My Car thread: http://www.turbominis.co.uk/forums/index.php?p=vt&tid=448825