knock threshold

[Sjogun]

I'm starting to tune on 93 after upgrading turbo, intercooler, e-throttle, and external wastegate on my version 4 STi.  it was previously tuned on e85, but we never got around to the 93 tune.  Ive got the VE table close to my liking at spring pressure(12ish psi).  now adding some more boost to the mix, ive noticed knock levels rising over threshold, no huge spikes, and not too far above threshold.  im wondering if its normal for 93 octane to be a little "noisier" than e85, and if its recommended to set threshold on the 93 tune, and assume it will be plenty above the e85 "noise" levels?   lmk your experience with knock theshold, and modeled multifuel strategy.

 

attached current work in progress 93 tune, and a log of a mild 4th gear pull.

added boost.pclx spull.llgx

[Adamw]

No, knock level wouldnt usually change noticably with fuel, most influence comes from cyl pressure - so MAP and ign advance.  Usually you would have less advance with less ethanol so I would expect knock level to drop with petrol provided boost was similar.  

I notice your threshold table uses TP on the axis so that could potentially be some of the issue if it is reaching a higher boost for a given TP (you are only at 30%TP in the log).  

[Sjogun]

i see.  changing load axis to MAP would give better protection given higher pressures can be achieved with relatively small throttle input.  I'm not sure what number would be considered actual knock, and not noise.  My last tuner said it would be a pretty obvious spike.  

I'll change that load axis, and rebuild the threshold table, thanks for the input Adam.

[koracing]

Also pull more timing out of your pump gas timing table and see if it changes the knock readings lower.  As a starting point I would start with 6 degrees less on boost than your E85 table, and you're more in the ballpark of 3 degrees less.