Alternator upgrades

[Salteen]

So I recently purchased a 1000W amp. I started thinking on what I need to do and quickly realised that the factory 2.6L alternator may not be enough power. How big of an alternator is factory and what do I need to power the bluetooth radio and 1000W amp I have thrown into the mix? I read that factory is 45 and the upgrade is 75 and that's nothing to what I need. Please help, thanks!

[geezer101]

I wouldn't use anything less than a 95 amp alternator. It should have plenty of juice unless you are punishing it. I noticed you have a sealed Optima battery which is a good start. I've been running a Philips XP640 amp with a 7 speaker system (sub is a 12" SAS sub tube) and a car full of electric options, and so far the factory 95 amp alternator hasn't glitched on me.

[Salteen]

The factory is 95 amp? Ok then that should be plenty. I read somewhere that it was 45 but wow that's good. Thanks geezer!

[finalfighter]

i believe its actually 45amps. every truck that ive looked at was 45amps. i have a 92 & 90 and both have 45amp alts, ones oem with 125,000miles on the truck and the other needed rebuild at 165,000.

[Salteen]

Hmm, I found online that you take the watts and divide by the volts and multiply by efficiency and that's the power. It's a class D amp so like 80% efficient, so say a baseline of 12 volts. 1000/12=83 and 1/3 that x .8 is 66 and 2/3 amp needed to run at 12 volts. So at minimum I need like 65. I would not like pushing the limits as the upgrade I found is off a van and offers only 75 amps. Now at 14-15 volts (normal highway driving and such) it requires about 50 amps and that's where I will spend most of my time on my hour 45 commute from my town to work one way. It's mostly interstate and highway and I usually go about 90+ on the interstate and like 65-75 highway.

[geezer101]

Sorry I was referring to my daily (the Hung Dog wagon). Stock truck alternator is 45 amp which is terrible lol. The van alternator is the best bolt in alternative but it will struggle once you crank the audio hard and you have your headlights etc on.

[Salteen]

i figured thats all. in that case I may as well just run this setup in the 95 yota. I like it better anyways because of a series of reasons that I will list in my build thread