BAD POP NOISE

[Mont]

I have a pop noise everytime I start out from a stop light or from reverse to drive forward. I have lifted to car up to look but it won't do it, I think the car needs to be on the ground to do it. I have checked all the bushings, driveline, trans mounts. Everything I know of. PLEASE HELP

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89 LX Supercharged DSS 357, 11 lbs Powerdyne, Downs Box intake, ported GT-40x heads, lockwired, Crane Cam 1.6 rockers, Crower cam, Oil cooler, Moroso oil evac kit, Taylor 10mm wires, MAC 70mm T/B, 36lb injectors, Vortech fuel rails, Pro M 80mm Mass air, Vortech T-Rex Fuel pump, 255lph intank pump, K&N, Cobra R radiator MSD6-BTM, Lakewood bellhousing, Tremec Trans, Pro 5.0 shifter, MAC headers and X-pipe, Dynomax race mufflers. Dyno at 519hp to the wheels. And more to come.....