Mek-a-nik wrote:I haven't looked into it yet, but I thought that cooling fans draw a lot and need more amperage. Maybe something like this: http://www.summitracing.com/parts/sum-810340
How many amps is that alternator, Bo?
Amps are normally less than 15a for 12v automotive cooling fans, typically around 10 amps if spec'ed in Watts (amps=Watts/Volts) ie 90W/12v=7.5 amps, a control relay is required, similar to a horn relay because the electric temp sensor thermostat contacts are not rated to operate the fan load, the temp sensor operates the fan power relay. I think you will have no problems using your 60 amp alternator. If seriously considering the 100 amp alt check the dimensions of the alternator housing. On some vecs a different mounting arrangement and belt is required. A good automotive parts person can check fit specs and tell you if a install kit is available or required.
Also if you have to make a long run from the isolator to the aux battery, like under the chassis thru metal holes, etc, later model fords plus others have large bolt mount fuses that now fuse the alternator OUTPUT wire and are sized around 160 amps or more that are dirt cheap. I would consider using one of these type fuses in the aux battery wire at the isolator or in the Alternator output lead before the isolator.
This alternator output fuse in the later model vec's prevents a completed melt down of the wiring between the alternator output and the battery if a diode shorts in the alternator and/or if Bubba hooks up jumper cables ass backwards and the diode3s in the alternator are drawing a high current due to the reversed connections. (and possible battery explosions) Some older model vec's did not fuse the alternator output. Some older Fords also just used a fuse wire that was smaller than the large alternator wire and it would BURN the wire apart. (color code fuse link wires for different amperages) GM used a similar fuse link.
Also if your vec has a fuse link it's usually sized per the alt output and would probably need to be sized per the upgraded alternator. some GM vec's had their fuse links located underneath by the starter solenoid and not user friendly to replace the fuse link out on the road or even in the driveway. (battery would not charge if the link burned out and sometimes the link would just go bad (open) due to old age/engine heat/vibration)
