More megasquirt questions.... Options

[Joe Bob]

Not getting any response on the shop talk forum....project is a blown Type 1 motor. It's a stroker 92/82 displacing 2180ccm and it has the Hideaway turbo kit from CB Performance with a HEI ignition. We put on a Megasquirt-II instead of the Delco ECU to get more tunability. Now I am looking for some pointers for the ignition table. Here is what I came up with so far. Please give me some feedback.

(IMG:http://members.cox.net/3.6/images/spark.jpg)

[lapuwali]

MS has a trigger offset value that you can set to anything you like, depending on where the trigger is statically timed wrt to TDC. The table values represent crank degrees with that offset value considered.

That's one thing about the software they get right. If you think of the most flexible, most sensible way to do it, they do it that way.

The SDS way of a RPM/degrees "map" and another "retard degrees based on vacuum" makes sense to people who are used to distributors, since that's exactly how a vacuum distributor works. The 3D map that MS uses allows more flexibility. If, for example, you want more advance at cruise, and you cruise typically at 3000rpm, with a MAP of 60kPa, you can set that, but have less timing at 3000rpm under boost. Setting more retard under boost as SDS does will do the same, but it will pull the same amount of timing at 6000rpm as it does at 3000rpm, when you may actually want to pull less (or more).

That said, more degrees of freedom means more ways of screwing something up, so the SDS philosophy isn't at all bad, just different.

As to the values in the table, 46 degrees seems insane to me.

Is this a hot street car, or a drag car, or what?