Reply To: Ignition Timing

Hi again all,

I have come to trouble you some more.

In the course of writing the article for FP, all sorts of things have started to come to light.

It may well be that a lot of this has been discussed before but it’s all new to me.

I found this article on replacement distributors which shows the potential pitfalls of re-manufactured/substitute distributors and the worrying side effects.

http://www.theminiforum.co.uk/forums/topic/295669-distributor-advance-curves-re-manufactured-distributors/

I then started wondering about electronic units and had a look on the 123 site. I don’t know how many people are using 123 units but their site seems interesting.  They offer downloads of custom advance curves that you can put into your electronic units.  Has anyone used these or created their own custom curves?

https://www.123ignitionshop.com/gb/content/11-123tune-curves-download-page

I don’t know if I am interpreting the program for the Perfo engine correctly but it definitely seems to be based on the centrifugal curve in the manual. It starts at 700 rpm and advances to 24 degrees (engine) at 3400 rpm.

The vacuum curve however, (again assuming that I am reading correctly), appears to do nothing until a vacuum of 30 kPa and then at 31 kPa bangs on 20 degrees of advance. Not really what it is required.

I am hoping that there are members who can enlighten me.

Roger

PS Sorry, I have not worked out how/if one can put hyperlinks in messages.  You will have to copy and paste the links.