Alternator preferences

[bmxr152]

I have the newer style 185amp J2 fab and all i can say is its night and day difference from the ebay made in USA specials and ford remans. I hold a steady 14.2 at idle and see no less than 13.4 any other time, loaded or at WOT. That is seeing voltage with my SCT. I highly recommend the J2 fab.

 

[03cobra#2]

My data logs looks exactly the same with a Mechman alternator. I don't like it but it's never caused an issue. It's important to remember that the voltage shown in logs is 0.5v lower than actual voltage at the battery. If anyone has a data log with a J2fab alternator it would be interesting to compare.

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I have a online special for my alternator. My idle / driving voltage is around 13.8-14. At wot it dips down to the low 13 range. Keep in mind in the tune there are parameters for the fuel injectors to compensate for a decrease in voltage so you don't go lean. I think Ford knows this is normal.

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[cj428mach]

- I had the battery light flickering issue. Solved with an extra ignition switched power wire to the alt but it shouldn't need that.

If the Mechman dies I'll replace it with a J2 Fab.

Fyi that extra wire they have you hook up to keep the battery light from flickering is a joke. My mechman blew up and the extra wire keeps the battery light from coming on period. Thankfully my aeroforce told me what was wrong so I could hurry home just before the car died.

I believe the mechman and j2fab are both just denso alternators with aluminum cases to fit our car's so the internals should be the same. That means pick the one you want based on price, customer service or warranty.

 

[Stage 4.6]

I believe the mechman and j2fab are both just denso alternators with aluminum cases to fit our car's so the internals should be the same. That means pick the one you want based on price, customer service or warranty.

This i did not know?