[verdell]

Originally Posted by 65k10

Okay,

It's summer and daily temps are 110 plus. I've got a 66 C20 with a 383/700r4 with a 4 core factory radiator (recently recored) with 2 12" electric fans. Without the AC on, stop and go traffic temps are in the 210-225 range (mechanical gauge in intake). With the AC on (and it's not blowing that cold), it gets to 235 before I panic and turn off the AC . On the freeway (without AC), temps are a steady 200. Using a factory serpentine set-up so I've got the correct reverse rotation water pump. Engine has a mild cam, long tube headers, aluminum heads and intake. 7lb cap on radiator, and it has never puked out any fluid. If the air temp is 95 to 100, I still see the same motor temps, but the AC is cold, cold, cold. I dropped initial timing from 12 to 9 and that has helped some, but definitely can tell performance has dropped some.

I feel that maybe the fans aren't doing the job and maybe I need to step up to something like the big 18" Lincoln fan. I built this to be my daily, but no AC in the summer is a disappointment. Any input is appreciated.

Thanks.

I ran an iron head 383/700R4 for several years with Summit aluminum radiator and a '96 Mercury Cougar XR-7 big 2-speed fan on the low speed without ac and it never rose above 185. Summers here get above 100 too. I kept the same set up with my LS and Vintage Air but using the high speed as needed and it's still doing well. Maybe not moving enough air?