Hello.

I fight some spark retards. It most on acceleration and de-acceleration. My sparkplugs looks nice, no sign off detonation. My WB show rich condition during acceleration.
I lower spark advance up to 5 degrees in those areas, with no change in retard.
My exhaust is very loud. I start to think this is false knock.

Engine is

hotcam
lt1 intake
TF alu heads
fordge bottom
comp is 10:1.

6spd

If you got time could you look at my datamasterfile, and perhaps you se something i missed.

I also provide my spark tabel, it basic my stock vette spark tabel, with less agressive crusing timing. I use +5 during PE.

Thanks.

scanfile:
http://www.vetteforum.org/attachment...=&postid=18109

 

I took a quick look at your file and saw something interesting.
Bring it back up on your screen and make CCP DC one of your parameters on the graph.
Each time CCP DC is off, your spark goes with it.
Not sure of the relationship there but is definatly some part of it.

Seems to be capping the advance at 27 or so when the CCP is off.

 

hmmmm interesting, going to look in to that.