Ign BAT vs ECT Comp

[iammike]

Just browsing through maps looking at things and I noticed a very large difference between the v210 and v231 maps.

The Ign BAT vs ECT Comp (lowers final timing value based on BAT's or ECT's) in v210 is WAY more aggressive than the one in v231 despite the target timing values being the same between the two maps. The Comp % Used is also the same between the two maps.

I've always heard of people having more problems with KR on v231...thinking this could be a contributing factor.

Thoughts of the tuner heads? To be honest, the v210 makes a lot more sense to me.

v210vsv231BATComp.jpg

[Lex]

In V2.10 the values are OEM. COBB decided to change these around in V2.31.

[Code Monkey]

My freektune is similar to the v210, I was getting knock road racing on the map similar to the v231.

[iammike]

Yeah, to be honest, the v231 seems ridiculous to me. I really wouldn't think you would want to run the same timing across that huge temp range. More when cooler, less when hotter, makes a hell of a lot more sense to me.

I don't believe I've ever seen my BAT's hit 173.

[Code Monkey]

My BATs hit 200.75 at the track.

[iammike]

Originally Posted by Code Monkey My BATs hit 200.75 at the track.

Show off. lol I've not tracked so that would explain that.

[Caldazar]

anyone from Cobb care to explain why they did it this way? I am sure there is a reason for it. Especially if its as simple as it seems on the surface

thanx!

[snailD]

these tables seem slow to respond in real world conditions so they need to be more agressive in order to work correctly. cobb changing them to such low values is likely causing KR with excessive heat because they pretty much wont change ignition values at all.

[iammike]

Ran a little test. Took my current tune and made two versions, one with the BAT vs ECT Comp table zero'd out and another set to retard timing by 5 degrees in all cells.

Behaved as expected when also taking into consideration the "Ign BAT vs ECT Comp. - % Used" table.

At ~6200 RPM on the first map, spark advance was 11*. On the second map it was 8.5*.

While all that is probably obvious to a lot of us, for anyone just messing with tuning, just thought I'd lay that out there.

Requested Timing - (Ign BAT vs ECT Comp A/B * Ign BAT vs ECT Comp % Used) - Knock Retard = Actual Spart Advance

That's what I've come up with anyway.