Diablosport Forums

duster360 wrote:I'd remove 2 degrees of timing from 4k-5k and retest.

Be sure to disconnect the battery to clear the 1 degree of LT knock retard before testing.

Do you have a wideband O2 at all? A reading of actual A/F would be nice.

daswi wrote:

duster360 wrote:I'd remove 2 degrees of timing from 4k-5k and retest.

Be sure to disconnect the battery to clear the 1 degree of LT knock retard before testing.

Do you have a wideband O2 at all? A reading of actual A/F would be nice.

I do not have a wideband. In your opinion, what should removing 2 degrees of timing do for me?

duster360 wrote:

daswi wrote:

duster360 wrote:I'd remove 2 degrees of timing from 4k-5k and retest.

Be sure to disconnect the battery to clear the 1 degree of LT knock retard before testing.

Do you have a wideband O2 at all? A reading of actual A/F would be nice.

I do not have a wideband. In your opinion, what should removing 2 degrees of timing do for me?

The idea is that you should make more hp with 2 less degrees of timing and 0 KR than with your current timing and 6 degrees of KR. Removing 2 degrees of timing should hopefully prevent the PCM from forcibly removing 6 degrees via Knock retard. Knock begets more Knock. So usually if you can keep Knock from starting you can keep it away entirely.

Your knock is starting around 4000rpm and gets progressively worse up to 5500rpm. After your shift it peaks again around 4500rpm. So removing the 2 degrees from 4k-5k should help quite a bit.


Also,,datalogging a more "comprehensive" list a PIDs will help you(and others) understand what your adjustment are doing.

KnK ST Retard
KNK LT Retard
KNK Total Retard
Actual Spark Cy1( you can do other Cyls but there's USUALLY little difference)
Spark adjust
RPM
MPH
THR POSN
AV MAP TO USE
1/1 LONG TERM ADAP
2/1 Long TEM ADAP
PRATIO
ECT
ACT
OPEN LOOP FA

Quick wrote:No........ It doesn't remember anything from the last time your floored it

Illss1 wrote:Not to threadjack but is it a MUST to disconnect battery if ur getting 1.0 - 1.5 deg of LT knk retard ? I just added fuel +2 % to the already +6 and it went away but i still got the ST knk 3.0

duster360 wrote:

Quick wrote:No........ It doesn't remember anything from the last time your floored it

This is completely false in reference to any Long Term adaptive learning(Lt fuel trim or LT knock).

Long Term
The second fuel correction program is the long term adaptive memory. In order to maintain correct emission throughout all operating ranges of the engine, a cell structure based on engine rpm and load (MAP) is used. The number of cells varies upon the driving conditions. Two cells are used only during idle, based upon TPS and Park/Neutral switch inputs. There may be two other cells used for deceleration, based on TPS, engine rpm, and vehicle speed. The other twelve cells represent a manifold pressure and an rpm range. Six of the cells are high rpm and the other six are low rpm. Each of these cells has a specific MAP voltage range Typical Adaptive Memory Fuel Cells . As the engine enters one of these cells the PCM looks at the amount of short term correction being used. Because
the goal is to keep short term at 0 (O2 Sensor switching at 0.5 volt), long term will update in the same direction as short term correction was moving to bring the short term back to 0. Once short term is back at 0, this long term correction factor is stored in memory.

duster360 wrote: Lt fuel trim is usually inactive at WOT because its driven from the feed back of the upstream O2 sensors, which are ignored in open loop. LT fuel trim can pop up at WOT level P-Ratios from timie to time.

The values stored in long term adaptive memory are used for all operating conditions, including open loop and cold starting.

mnunes wrote:I believe that simply loading a tune clears ALL of the adaptives, long and short term, so there shouldn't be any need to disconnect the battery.

mnunes wrote:I believe that simply loading a tune clears ALL of the adaptives, long and short term,