Added 2.5 gals of E85, filled up with premium. Did at least 3 WOT pulls with Sport ON and no sound. That said, zero hesitation/missing all the way up to redline. Had a tuned 997TT owner as a passenger with me for a second opinion. Will run tank down and fill with good quality premium again, do pulls again and see what happens. Could have been a bad batch of fuel combined with new tune (hopefully). With no perceived missing or any other indicators, could there be a slight issue with the tune programming that could cause this?

 

I'd datalog it now more than ever, your ecu might be pulling timing to save the engine, hence sees to run better.
C

 

So on all three WOT runs your digital display held 17+ PSI on boost?

 

Yep, not a problem getting boost right up.
Can I datalog and get enough info from a Durametric to see what's going on?

 

A418t81>> Check this thread out..

https://rennlist.com/forums/996-turb...ger-debut.html

 

I glanced through the thread and couldn't actually tell if the project ever came to fruition? It also looked like it was going to be expensive at around $400. That's substantial just to use a couple of times to make sure your flash is running correctly.

Frankly, I'm still very surprised that durametric hasn't / won't add cylinder specific timing retard.

Glad to hear that your knock issue seems to be improved. Since you made two changes, I can't tell which one did the job for you. The MAF sensors are very sensitive and not very tolerant of chemical cleaning, but occasionally it works. Let us know if the detonation comes back once you fill back up with regular 93 octane.

10k on plugs is fine.

 

Thanks, A4. Will definitely provide an update after I burn through this tank, refuel and re-test.