well there you go, KHA said you need batteries or/and an alt. And I have never gone wrong doing as he has said. so I guess you need some upgrades.

but here is a logic question I do have. I know the purpose would be if all things are running, but I just thought about this. shouldnt you just assume the a/c amperage pull instead of a/c and heated seats, since it is the higher of the two? at what point would you ever run heated seats and a/c?

 

A/C is used for defog with heat and seats.

 

Yep, looks like it! Well crap, a little more to pay for. Still, I can drive over to my old high school and tell the kids, "Hey, look at my awesome new wires! Don't even act like you aren't jealous!" And yeah, my mistake, I should have specified defog when I said AC and heated seats.

Alright, back to business. Let's see if I've got my power requirements right: I'm shooting for a 4 ohm sub with Class D amp, in the neighborhood of 600W RMS. 2-ways up front at around 80W apiece, and mid-range drivers in the back at about 40W apiece. So 840W. Figure 85% efficiency from the amps and we're looking at 988W, divide by 13.8V and rounding up we get 72A peak - 24A continuous. Sound about right everyone?

So the Big 3 will be a definite must, and based on even the most optimistic projections, it's almost guaranteed my alternator wouldn't be able to keep up at idle (thanks to both you guys for making it clear for me). Still studying up on caps, but I'll probably be looking at snagging some.

So, on to the questions. Is there a formula for determining my desired alternator output? Surely if there's one thing I've learned these past 2 weeks it's that nothing is simple with this stuff. So it must be more complicated than 130A (my current capacity) + 24A. Once I've got a good estimate to work with, what other factors should I think about when choosing an alternator? And what brands would you recommend? I've found several options, like a 240A model from Mechman for $400. Again, I'm using the 4-cylinder engine.

And while we're on it, how about good sources for Big 3 kits, who do you use?

Thanks and cheers!

 

for the big 3, just get you some good 0 guage wire. I like knukonceptz and some terminals.

mechman is a popular alternator and so is iragi. it is hard to determine with alternators which is the best. I run an excessive amperage alternator and have never had any problems out of it, however, I know quite a few people who have had problems with them. tenny is a good alt, but they fall in with the argument that iragi and mechman do. its just one group slamming another. should all be good alt. The only brand I have never heard anything negative about is DC power. but you will pay a pretty penny for it. or you can have one custom built.

 

Quality Power makes a good product, as do Ohio Generator.

 

Cool. Mechman looks good, and I like what I see with DC but they don't go past 2007 for the Accords on their site - I'll call to ask about availability for 2009 when the time comes. I've been seeing posts by people with HO alternators who have problems with heat, and they do all sorts of crap for it from flushing their coolant to swapping out the thermostat. Any idea what's up with that? Poor installation maybe? Weird things happening with voltage possibly?

 

oh hey, just saw your post there. I'll keep those in mind too.

 

Links to threads where people are discussing problems?

Quality Power has a 250A for $400 for 2008-2012 2.4L engines

Honda Accord High Output Alternators