Popping and 4 to 6 degrees of knock

[83 intercooled]

Ok I just put a new trans in the car and plugs now the car is popping under boost and shows about 5 degrees of knock and that's easing into it or flooring no hesitation under cruise or light boost it happens around 20# any help appreciated thanks

 

[earlbrown]

If you're running pump gas and no alky that 20#s is most likely your problem. Also, have you replaced the wastegate hoses anytime in the last decade?

 

[RmvBfrFlght]

Be sure the plug gaps are closed up: .028" to .032"

Double check the grounds that are located at the back of the heads. IIRC, some may go under a transmission bellhousing bolt (not sure on this one)?

RemoveBeforeFlight

 

[83 intercooled]

Car has alky and yes hoses been changed and autolites gapped at 30
Grounds are good I had this problem before but oh well back to Andersons it go