Setting up an initial ignition timing table

[arny528]

I believe it wouldn't be hard to do, it might use a slightly modified VE generator because it would be based on max torque and max power areas and calculate the rest in a similar fashion. Probably some stuff should be entered, like desired AFR's in idle and cruise areas.

Or maybe it could be derived from an existing VE table? Is the VE formula close enough to derive AFR's, or it should be derived by another interpolation method?

[Leistung Elektronik]

Finally, for boosted engines, you subtract 0.3° of advance for every kPa above 100 (it's not a coincidence that this is the same factor as for the 'vacuum' adjustments). Because 101.3kPa=~14.7psi, this works out to ~2° per pound of boost. It is often the case that you want to limit the retard under boost as well, typically so that it takes out no more than about ½ of the maximum advance at 100 kPa.

Lance.

Hi Lance,
I don´t understand because you substract to much advance degrees when the engine ist under boost. We run a 1.6 L Fiat engine under 30 PSI of boost with 22° final and no detonation. What ist wrong?? Have you considered any CR (9:1 ; 10:1 ; etc) ?
I apreciate your help, because i´m trying to find a simple metod for make a start advance table for boosted engines.

Thanks

[preston]

It doesn't appear that MSII can alter timing based on IAT. Isn't this pretty common on the normal aftermarket EFI setups ?

Is anyone working on adding this ? (why or why not ?)

I've heard rule of thumb there is -1 degree per every 10 degrees above 120.

[Bernard Fife]

It doesn't appear that MSII can alter timing based on IAT.

Preston,

It would be pretty easy to change the code to make the current CLT based spark adjustment be based on IAT instead. It would be a good project for someone to 'get their feet wet' in MS-II programming.

Lance.

[mad max]

Finally, for boosted engines, you subtract 0.3° of advance for every kPa above 100 (it's not a coincidence that this is the same factor as for the 'vacuum' adjustments). Because 101.3kPa=~14.7psi, this works out to ~2° per pound of boost. It is often the case that you want to limit the retard under boost as well, typically so that it takes out no more than about ½ of the maximum advance at 100 kPa.

Lance.

Hi Lance,
I don´t understand because you substract to much advance degrees when the engine ist under boost. We run a 1.6 L Fiat engine under 30 PSI of boost with 22° final and no detonation. What ist wrong?? Have you considered any CR (9:1 ; 10:1 ; etc) ?
I apreciate your help, because i´m trying to find a simple metod for make a start advance table for boosted engines.

Thanks

read this:

http://www.innovatemotorsports.com/resources/myths.php

[Leistung Elektronik]

Thanks, i have read it! But it have no information about CR, timing...just a few words about peak pressure and others.
Have you any information about a site with more specific information.

[burgo90]

does anyone know anywhere on the net i can get excel??

[TT350chevelle]

Did you try this:
http://www.microsoft.com/downloads/deta ... laylang=EN

[burgo90]

yes i downloaded that but its only a viewer so i cant put my own values in to create my own table

[Kirk]

yes i downloaded that but its only a viewer so i cant put my own values in to create my own table

Try http://www.OpenOffice.org. OpenOffice is a free office suite that appears to handle this MS Office spreadsheet.