update: I posted here and then created another thread (link below) related to my block casting number where I did put some updates; however, I think I will bring the focus back to this thread. I picked up the car about 2 months after the previous post. I took the car home as is and drove it rather conservatively, always confused at why it pinged at WOT only in the 3200-3500 rpm range. I bought it home and took it to get fine tuned hoping ping would go away. I was convinced I had enough carb based on some 'expert' advice and online CFM calculations and countless number of people who ran big block chevys and other similar CI motors with a 750 cfm. After quite a lot of Dyno Chassis time (fall of 2014) and an upgrade to 800 edelbrock 800 AVS in the configuration below, AFR at cruise was shown to be 14:1 and at WOT ~ 12.5:1. Power was ~ 330whp and 380 ft lbs. However, it still pinged at WOT and was told my CR was probably higher than 9.5:1.

Details on motor:
CR goal was planned for 9.5:1. I was told by butler my planned carb, 750 edelbrock wasn't going to be big enough and it would ping.

Specifics:
400 block
bored 0.40
butler stroker internals (kit w/ dished pistons 6cc) and steel crank
#62 heads (74cc)/hardened exhaust ports (not ported)
XE284H Comp Cam
Mallory Unilite Dizzy (no vacuum) w/ new cap and button; told 30 degrees total (not confirmed) no vacuum advance
Edlebrock 1813 carb - 800CFM (w/ 116 secondaries)
Holley Street Dominator (300-9) intake (single plane)
MSD coil (blaster High vibration)
Accel Spiral Core 8.8mm spark plug wires
NGK V-power XR4 spark plugs
TH400 w/ 2500 stall converter
3.23 gears
New Edlebrock Fuel Pump

https://firstgenfirebird.org/forums/ubbth...3242#Post293242