TL...shows knock after boost, in the vacuum w/ no throttle

[87owner]

Is this like a delayed reaction or some kind of transitional knock? If I boost up all is well, no knock at the hightest boost levels, But just after letting off it creeps up. Usually the next frame after max boost, even if the car has returned to vacuum. Should I associate the KR with the frame before it, or is it false.

 

[blackbuick87]

How much timing is in your chip? A high timing chip on low octane fuel will cause this

 

[87owner]

stock chip, 94 octane from Sunoco. I have heard people say that their cars just didnt like sunoco ultra 94, maybe thats it.

 

[blackbuick87]

Stock chip actually has quite a bit of timing. A Thrasher 92 or a chip from another vendor should solve your problem, though you will need a 237 reg and a 160 thermo to run them