ERAUMAZDA

So I have my H4 head lights. They give me better view of the road, but it sucks that the 7 is limited to like 55 watts. So what should I do to allow for 80 watt bulbs or 120 watt bulbs.

I'm guessing the wire and relay can not handle it. However I don't want to overload the alternator. Any ideas.

Icemark

Upgrading from a 55 watt to a 85 watt bulb only increases the amp draw on the system by 5 amps total (about 2.5 amps additional per bulb).

That is well within the specs for the stock electrical system, however I do recommend some conductive grease or diaelectric in the sockets to help avoid corrosion or additional heat problems.

However the stock system can not support a 120 watt bulb as the current increase is considerably more than double the stock draw.

Trav

I would assume an upgraded alternator would help the situation overall? Considering a FD alternator or something myself -- just curious...

Icemark

well as far as for a bulb upgrade yes the upgraded alt would help, but you would also need to re-wire the headlights with to support more than 90 watt bulbs.

I am mixed on the idea of just upgrading the alt for the heck of it. If there is a need (you have upgraded bulbs or extra driving/fog lights and have a non-stock stereo system, etc) then there might be a reason to spend the time money and minor increase in weight for an upgraded alt.

But otherwise there doesn't to seem much of a point. The stock sized alt is more than sufficent to run stock or minor modded electrical systems.

I would be upgrading and replacing all my battery and engine grounds first.

Ryde _Or_Die

Should the battery fluxuate so much during driving? Like it will go from say 12.5 to like 14.3 or so just from hitting the gas. Is this normal? I have a new S5 alternator and a pretty new battery.

Icemark

No, it should not. It really shouldn't even be dropping under 13.4 volts even at idle with the air condition, and brakes and lights on. If it is then the connections or alt is bad or failing.

are you sure it is new and not "rebuilt" from the local auto parts store?

ERAUMAZDA

thanks

ZenkiFC3S

What goes into installing the FD altenator? What are the advantages vs. disadvantages? Just wondering

NZConvertible

Fitting an FD alternator to an FC

Ryde _Or_Die

No, actually I know it is a rebuilt one. I don't have an underdrive pulley or anything. It happened ever since I got it. You really think something could have been wrong with my alternator when I got it?

Icemark

Its very common for "rebuilt" alts to have only the parts that have failed replaced rather than everything that should be replaced, replaced.

This will cause them to fail very early compaired to a remanufactured or new alt. Sometimes rebuilt ones will be bad right out of the box.