My 82 K5 is loud as all MMMM 350cid (built)holley carb edelbrock intake hooker headers racing cam and injector needle other internals beefed up to, 700r4(standard?) 33"x12.5x15 wheels but when I put the foot down it doesn't go as I expected it, I know it's a heavy vehicle and it does shift but it takes a long time to get it to shift,
anybody out there with any ideas?
we are talking 0-60 in 15-20secs possibly longer with about 350-400 horses[:@]

(shift=fast)

More info needed....

What kind of intake exactly?
What are the specs of the cam?
What is the gear ratio?
What kind of ignition?
What is your timing?

To be honest I'm not to sure of any of those questions all I know is the engine came from a racing camaro and the gearbox was origionaly mated to a 4.1 straight 6 petrol

Sounds like you need to either adjust the kick down cable (if equiped - don't have much experience with the 700r4) or find out if it has a vacuum modulator and make sure that the vacuum like is hooked up. Also, are you sure that the carb tuning is correct. You could be going way rich at WOT causing it to dog!