Is it worth it to upgrade to parallel flow condenser?

[alpinewhite318i]

I have upgraded to r134 on my 86 325es with a Seiko compressor out of 91 325i. The air blows cold on the highway even in 90 degree weather. But as soon as I get in stop and go traffic it's not that cold. I am thinking it's the old style condenser? Is it worth the effort to install a parallel flow condenser? Or any other modifications that I might want to consider? The aux fan is definitely working!

[cory58]

From what I've read, a pf condenser and 134a expansion valve would make a difference.

[nrubenstein]

It helps a little, but unless you go to an oversized unit, it's not going to help that much.

Bypassing the aux fan resistor (you'll also need to up the fuse to match the high speed fuse, 30A IIRC) makes a lot more of a difference.

Even then, I can tell you that it's not going to be perfect when stopped. I have high speed aux+sanden compressor+PF condenser in my 325is and while stopped in 100 degree weather, it blows about 60 degrees. When moving, I get down to the 40-42 that the thermal probe allows.

[alpinewhite318i]

I have the earlier version of the aux fan resistor that has the red and black wire screwed onto it. How do I bypass it? Or can I just reverse the red and black wires were the connect to the resistor?

[nrubenstein]

I have the earlier version of the aux fan resistor that has the red and black wire screwed onto it. How do I bypass it? Or can I just reverse the red and black wires were the connect to the resistor?

Bridge across.

Note that this can and probably will reduce the life of your aux fan.