Club Triumph

I have recently obtained and installed the “Amethyst”
Performance Mappable Ignition System for my 1972 TR6. The Amethyst is designed to replace the
centrifugal and vacuum advance units of our distributor.
The 1972 year Triumph was fitted with a vacuum retard module only, (the vacuum taken from the rear carb).  

I am looking to find information from  someone who has fitted and tuned this ignition system so we can compare notes.  What MAP characteristics did you did you try for the advance curve...and which one did you eventually settle on.  Did you configure the vacuum advance or not enter in any values?  If you used the vacuum advance - where did you obtain the vacuum from?

I would also like to find out if someone has a copy of a vacuum curve that I could use.

Thanks
ibjean325


Thanks

Hi

Not used the Amethyst system but have been using the Megasquirt system (with FI also) for some years with good results and the ignition tables should give some clues.

Two tables are shown.

First is the one used on my 2.5PI
Second is the one used on my Vitesse 2L

Neither will necessarily be right for your engine but should give a starting point.  The full throttle line (100kPa) from the 2.5 will probably be closest for your engine.

You definitely want to be using some vacuum advance which makes a HUGE difference to part throttle torque and fuel economy.  

Cheers

Nick

Thanks for the information I will plug them in tomorrow and let you know.
Any suggestions on the vacuum, advance?
Originally my TR only had a vacuum retard that operated at lower RPM-an emissions feature.
Thanks