I used the Mk3 Supra intercooler and its junk for the following reasons:
1) Large pressure drop across them. The reason these intercoolers are so available is that this is on of the first upgrade the Supra owners do.
2) They are not cross flow
3) See the poor design on the end tanks, well they are well known to rip the aluminum at the end tank that is opposite the side where the intake and outtake pipes are...the aluminum is very thin on these intercoolers. Lift that Fisher Price made Supra intercooler and then lift an equally sized Spearco, HKS, Apexi and you will see the difference in quality and construction
4) The fins are a very old design that damage easy and cool inadequately.
If you are going through the massive effort of putting an intercooler in your Z, at least put a good quality unit and then you don't have to do things twice.
Yasin