MSefi.com read only forum (Jan.15,2018)

Hey guys,

I've been tuning along for a while now, and I've moved on to adjusting the spark table.
I think I've found the upper limmit for idle advance, and I've been backing off that area with improvements. viewtopic.php?f=89&t=31733

I'm still sneeking up on the max advance. This 340 has a bore of 3.75" and I'm running regular gas so the upper limmit "should" be 34ish. I'm trying 32 this week.

However, what should I be looking for while I adjust my timing advance ramp?
For instance, If I put more advance in about 1200rpm (light cruze) what should I see when I start to reach the upper limmit?

Also, as I advance the timing, will I see any changes in ve requirements at that specific area on the map?

[EDIT] Oh I forgot to add, I'm mainly tuning for economy and drivability. So I think I should be looking for more advance (more torque right?) so it should require less fuel/trottle for a given speed right?

Thanks
Thom

Whelp, after quite a bit of experimentation between the spark and VE tables I've gotten quite good results.

The basic results were:

1) Increasing advance pulls more vacc at cruse (up to a point)
2) no real change in VE requirements noticed.

I think I'm running more efficently now because of the shift in Vacc, showing less throttle is required for a given speed.