[Slydit]

My car has a noisy cranking and occasionally I get rpm spikes while cranking that throws the timing to like 25 degrees as it comes out of "cranking mode" thinking it like 2000 rpm for just a split second... It'd be good if we could taper the ignition timing from cranking to timing table value so any noise doesn't instantly call for 25 degrees while cranking.

[PSIG]

Not to be that guy, but first reaction is to have you solve your noise issue so it's not a problem in the first place... That said, my first thought could be a filter switch, using a stronger software filter (if possible) during cranking, that switches to your selected filtering (off, weak, etc) at cranking or set threshold. Second thought is to try increasing your threshold to check transition effects for improvement. Perhaps other approaches. If no joy, go back to fixing the noise source.

[Slydit]

I've re done the earth's in 3 different configurations. Removed and cleaned all power and ground connections. It's a fairly stock mx5 with turbo so unsure why I'm getting noise on cranking.

[PSIG]

Use any method that will indicate the source of the noise. While I've used pocket AM radios, and oscilloscopes with short wire "antennas", you can also power or disable certain circuits to focus the search for noisemakers.

For example, turn everything off you can, and crank. Any noise? If yes, pull fuses or relays to kill circuits (fuel pump, coils, etc). At some point the noise will stop, or there will be nothing powered except the starter power circuit and starter (and a jumper wire powering the ECM if necessary).

I have found bad starters making noise that worked, but the brushes were poor and sparking. It can be anything electrical, so shrink the possibilities until you find it or the area of concern and begin testing just that stuff. Good luck!