2-Bar Woes

[dc_justin]

Cool, NAH can keep an eye on it and maybe put a little bit back in if required. It was set to 14* before zeroed. I guess the delta airflow values could also be increased to move the trigger level up too.
Lots of fun to be had tweaking

Yep.

I'll typically reduce the amount of effect BKR has by 50% on a N/A motor, but even that will trigger big knock with mine. Probably also has to do with the fact that the gasoline here is pathetic as well.

[NAH]

Yep.

I'll typically reduce the amount of effect BKR has by 50% on a N/A motor, but even that will trigger big knock with mine. Probably also has to do with the fact that the gasoline here is pathetic as well.

Well presumably I can add some BKR back in until the problem re-materialises, then back off a little.

Can someone give me some typical values for a s/c tune for B6210 Burst Knock Delta Air Mass & B6212 Burst Knock Retard (for reference purposes)?

I tried to open a boosted tune from Holden Crazy but it flashed up a PCM warning & the calibrations were empty.

In B6210, can the change in air mass be negative or positive? If so, what is the reasoning behind this?

Presumably I could log rpm/DYNCYLAIR & establish the delta air mass which could then be used to retard when boost was higher than normal?

Justin, is your Roots a centrifugal? I think the Vortech gives a more steady boost than screw type. Whith your BKR setting, to you notice the timing being pulled when you gun-it?

[dc_justin]

Justin, is your Roots a centrifugal? I think the Vortech gives a more steady boost than screw type. Whith your BKR setting, to you notice the timing being pulled when you gun-it?

Roots is a type of compressor, the way centrifugal is. I have a Magnacharger radix, and yes, your vortech builds boost in a much smoother manner.

I do have timing being pulled when I mash the throttle, as much as 20* or more being pulled. Without that, I'll have big KR spikes. One instance was 8* of KR that stayed peaked out for about 3/4 of a second before starting to fall.

When I was tuning the VE table, I experienced much of what you described in your original post at heavy throttle. When my map value would increase ever so slightly and start to interpolate with the next column of data, the PCM would calculate a large change in airflow and my timing would end up looking like a saw blade, bouncing between 15* and 10* or so...

[NAH]

Been looking at the Boost VE table. The settings were as 105kpa (Main VE table) to +300% for the last colume.. I have reduced the value to +150%. I have also added some figures to the BKR (max 4&#176.

Logging today showed KR recorded at less than 0.5 under acceleration (3.9 under throttle lift-off). If I set the BK Delta Air Mass with a higher number to a lower number rather than a lower number to a higher number, will this affect how the table is applied?

Also, I logged some runs today & didn't get above 140kpa manifold pressure but got 2.10 grams/cylinder. Is this right/possible as the Octane Tables only go as far as 1.20?

Anyway, gonna flash the modded tune & go for a run. Ho ho ho!

[ringram]

Probably yes. 2.10 sounds ok. But it is likely to be affected by your high VE table values at present. When you tune them right the value is likely to come down. Timing will be either the last row on your timing table. Or look in the COS3 additional tables there is an extra table there to tweak timing. A0010 is what you are after.