This is not for me, but rather a buddy. He has a 87 305 TPI in his 55 Chevy and after hard accelleration, it won't come back to an idle without dying. If he shuts if off and restarts it, then it will idle.

Should add it's MAF

 

IAC maybe?

 

first check the tps voltage, note it. not enough minimum air. take and open up the butterflies 3/4 of a turn on the screw. check new, higher tps volts and adjust back down to whatever it was when you first checked it. assuming that initially it was within spec. .54volt. see what happens, it will take a little driving for the ecm to figger out you tricked it, but it will behave eventually. if the idle is too high re do the dance but turn in the screw a quarter turn. too slow still? out another quarter turn.