ok so i have this problem i have no clue what to do the car runs normal when in park but when i put it in drive it drops to 400-600 RPMs and then dies and if i try to press the gas to keep it going it still dies

 

kinda sounds like a vacuum prob, but that would kill the car in park also. what's your set up? carb ect. normally the engine will drop a few revs when put in gear, but it shouldn't die out.

could be it's not getting enough fuel. check your fuel lines/pump and the carb itself.

 

Make sure your line running from the back of the intake down to the tranny modulator is hooked up. Mine had fallen off and acted a lot like what you are describing.
Walt

 

also your carb can be tuned wrong

 

+1