20v Silvertop stock ignition timing and fueling maps

[jondee86]

This is the VE version of the ms fuel map shown above...



Looking at it seems that the whole map could be could be lowered by
20 to bring the numbers down to a more realistic level. However, with VE
maps the actual numbers are not important. It is the shape of the map...
the ECU calculates the correct fueling based on the input settings you
have entered, and the map just shows a picture of how the fueling varies
across the rpm/load range.

As an example, my s/c engine runs on a VE map that does not go higher
than 55 at any point (don't ask me why) Starting from scratch an
engine will usually run if you make a VE map with the first row at 50% and
the last row at 80% and adjust from there using the WBO2 gauge.

Tuning ITB's using MAP for load axis works well for idle and low throttle
openings if you have a stable MAP signal (averaged across all 4 throttles
and damped). But because the MAP signal drops rapidly as the throttles
open, the MAP signal will usually be at 100kPa by about 30-35% TPS.

Tuning by TPS does not work so well at idle and low rpm but works much
better for medium and high throttle openings as the fuel load is varied by
the throttle opening all the way to 100% TPS. The ideal situation that is
adopted by many ECU's these days is to have a "blend" of MAP and TPS
load control. MAP control at low throttle gradually changing to TPS as the
throttle opening increases... best of both worlds

Cheers... jondee86