I am running a 91 Z28 with the 730 computer. I changed my thermostat to a 160 and wanted to turn the fans on earlier. I have been reading post about it so I tried it. Here is my dilemna. I can not get the fans to come on now with the chip changes. Any Ideas? The car gets way over the 220. I also read that the factory 730 does not control the second fan directly. I can work on that later. Thanks in Advance, BranZ

Here are my changes:

Fan 1 Enable = 73.98 c
Fan 1 Disable = 82.62 c
Fan 2 Enable = 76.78 c
Fan 2 Disable = 82.62 c

 

Switch the enable & disable temperatures. The enable should be higher then the disable.

RBob.

 

It makes perfect sense now. I was rushing when I made the change. I know it is not good to rush when burning chips for your pride and joy. Thanks, Brandon

 

The 7165 fan is only driven by the ECM.

On the 730 the primary fan is only controlled by the ECM. The secondary fan can be turned on by any one of three items. The ECM, temp switch in the block and the AC pressure switch.

 

For the secondary switch, if not opting to run it to the ecm on an unesed pin, a secondary/high speed fan switch from an 86,87TR or 89 TTA will get your second fan on at 205deg for some cooler insurance.(look at pics in app book to make sure u get the right one, looks identical to f-bod fan switch when u have the right one)

later
Jeremy