EACV up to 1992 = IACV after 1992
same part, same function. I guess before 1992, it sounded impressive to refer to an engine part as "electronic" hahah...
Honestly tho, i'd try cutting/removing the J1 jumper in the ecu and letting the car run off the stock program if the IACV doesn't help.
I don't trust those "JUN" race chips....
Also, make sure all the air has been bled out of the coolant. It has been known to cause this problem too.