Spark at 40?????

[killaz]

Hey guys. When i crusing in 5th or 6th my spark gauge on the scan tool reads 40. When i get on it a bit it varies between 22-32. Does this sound right? Where in the EFI tuning softwhere do i change my timing?

thx

[Tordne]

There are a few places:
1) B5913 High Octane Spark Table
2) B5914 Low Octane Spark Table

I would expect that you are in the High Octane table, there is a scalar PID to see the balance between spark tables. Both of these table are used when the TP% is above B5916.

3) B5932 Base Spark in Gear
4) B5933 Base Spark in Park/Neutral

These tables are used when the TP% is below B5916 and speed is below B5917.

For an M6 trans only the in gear table is used.

Cheers,

[killaz]

How do i gauge what to set my tables at? Do i need a wideband for this? Also will the auto ve help out with this?

[Tordne]

Spark is the hardest thing to tune IMO. As for the wideband. My personal opinion is that a wideband should be mandatory for tuning!

With spark you are basically looking to maximise the power at any given RPM vs. load point. You may be able to advance the timing a certain amount, but at some point you will get the onset of knock. At thins point you have gone too far :(

When knock occurs you will need to determine if it is real (audible etc.) or false. You should also check the actual AFR (which is where you need the wideband) to make sure the mixture was rich enough for the load. Looking at the commanded AFR is not sufficient for this.

If you are new to tuning the best thing might be to book some time on a load dyno and map the spark table, advancing and retarding till you get peak torque. This might also give you the opportunity to map the VE table, and get the optimum enrichment.

[technical]

40* doesn't sound unreasonable at part throttle cruise.

[SSpdDmon]

I get 40-41 when I'm off the gas all the time. As you give it gas, the timing will reduce. That's why the timing table looks like the side of a mountain.

[killaz]

ok i got it now, the way i had my spark gauge setup, was to turn red at 40, so i thought it was bad. LOL i know im a newb. Anyhow. At WOT im around 28 or so. Sounds good, and i get 1.5 degrees of KR at like 2,000RPS so i think this is fictional KR. You guys think i would gain anything form adjusting my spark? Or do i really need to be on a dyno for that??

[joecar]

ok i got it now, the way i had my spark gauge setup, was to turn red at 40, so i thought it was bad. LOL i know im a newb. Anyhow. At WOT im around 28 or so. Sounds good, and i get 1.5 degrees of KR at like 2,000RPS so i think this is fictional KR. You guys think i would gain anything form adjusting my spark? Or do i really need to be on a dyno for that??Post a pic of your log chart showing your KR and AFR.