Is it normal that your knock counts and spark retard increase with a modyfied engine and when using stock chip?
I got a vette with LPE heads,hot cam,headers. And when I look at my datamaster scans I can se knock and spark retard.
Mostley at lower speed crusing at part throttle, around 1700rpm.
Abow 2000rpm, almost no knocks at all.
Im going to have my car tuned. But im just curios. Is the stock spark tabel to agressive for my new setup, and cause knocks?

I checked the headers against the frame, nothing is hitting nothing.

Thanks.

Oh its a vette 1991 MAP car. Manual tranny.


Tanks

 

hmmm. a yes or a no will do hehe

 

Probably.
Tuning is about balancing timing and fuel. Too lean due to better breathing is another reason. Change in vac levels due to new cam can be a factor in where the engine runs in what location at what time, in the various tables.