4 replies to this topic

[fenghuang]

Have just watched the videos on the Accuspark website for their Blackbox ignition control box (as recommended by Moke Spider).

http://www.accuspark...uk/Blackbox.htm

It looks like a really easy upgrade and I even understand more than I did about ignition than I did 20min ago.
(This is not an advert and I'm not connected with the company!!!!)

 

But ...

I can't find any info on how to come up with your own ignition map.

The easy answer is obviously have a session on a rolling road and get someone else to do it, but I'd like to understand the process. So, suppose you were adjusting the mapping yourself, how do you figure out what advance and dwell to set? The Accuspark video looks as though additional software and equipment is neccessary - is that the essential, and is it the only way to do things? And if so, how would you set up something that works reasonably well to get you to the rolling road?

[djdanmk]

http://www.theminifo...gs#entry3103010

[Guess-Works.com]

The kit is basically two parts, the Dizzy and the black box..

 

The dizzy is a fixed unit so there is no vacuum or centrifugal advance, just static, what you should is set this to a fixed 8 to 12 degrees BTDC which means the car will start and run without the blackbox, a limp home mode if you will... The Black box then adjusts the advance electronically + or - depending upon your settings..

 

You can approximate an advance curve for a dizzy with something like a maximum advance of +20 degrees.

 

The whole point of having the blackbox is you can now spend some time on a dyno' or rolling road getting the 'perfect' advance curve for the engine rather than making do with an off the shelf curve.

 

I will generally suggest/supply one of these with any new engine I build.

Edited by Guess-Works.com, 22 February 2015 - 06:25 PM.

[l_jonez]

One thing to point out it doesn't have an ignition map ( you need a load option for that, TPS etc) this system uses an ignition curve.

In simplest terms you want the most advance at any point without pinking

[fenghuang]

I'll need to read the Aussie thread (it's long!!!!), and I really really don't want to seem ungrateful, but the question still stands.

"Limp home mode" may not be enough if, for reasons beyond your control, you need to use the car for a 100 mike round trip every day for the next fortnight and the nearest dymo is 75 miles away down a combination of country roads and motorway.

How can you tell when the advance needs increasing / decreasing and is it possible to get a half decent dwell curve without an oscilloscope?