Hi, i was just about to modify my friends cooling system that currently has dual pass, stock & zzp heat exchanger, and option b, but his IAT's are basically engine temp. most of the time. This can put me under the assumption that his pump is either out or on it's last leg and i know that with all of the stress from having both heat exchangers and how poorly everthing is ran that it needs to be redone well i'm getting rid of the Option B and going with the STU mod on this and taking the stock heat exchanger out. Here is how I was thinking of running it but i wanted to make sure i'm doing it correctly.

 

Keep the stock IC unit. The ZZP is not large enough to run alone

 

Where can you get the tank

 

you replace the stock filler neck with the stu mod

 

So if you just have an option B tank instead of that STU mod is that the correct diagram for running a dual pass setup?

 

It's either the pump or air in the lines. The ic pump in our cars is the same ic pump that is in the ford lightening, svt cobra, and in the supercharged mercedes as well. ALL the guys who run ALL theses different cars with this same pump complain of the pump going out. I was having iat issues and found that mine was out too. I replaced it and iat's went WAY down. I would say pump is the issue. I have the stock HE with the zzp S3 HE, option b tank, dual pass plate, and the pump works just fine.