I had the same issue on KT 120 last winter, and we opened up the pump limiting voltage and then did what you did and got the Acc Delay down to 3 before it began to huff on spooling up. I returned it to 4 and then locked the battery pump voltage back down to 700 I think. That was as far as it was willing to go and still accelerate smoothly. A very noticeable difference in spool times too by the way. I was running Jet A with KT oil and at sea level too.