Ive been at (and past) the fit's theoretical maxium power output with my subwoofer and door speaker amps for quite a while. Im interested in moving past the 1000+ rms watt mark that I am stuck at currently. However, with a screwy ecu that lowers alternator output at idle this may be a huge obsticle. Has any heard of any solutions yet for our GEs?

 

Nothing at all ? This is the only thing I dont like about owning a new car. There are some crazy things I want to do but I cant get started until I've got aftermarket support and a healthy suppy of parts from local junkyards. I'm not about to start cutting holes in my door panels untill I can just go to the scrapyard and buy a new one for $20.


I recently had to travel 160miles to a junkyard to buy an OEM rim for $75. The fit there was absolutely GUTTED. A local body shop had torched out a quarter of the frame for a collision repair (talk about high demand!). Every single piece of trim was gone. the dash, gone too. It was really cool seeing the Fit's skeleton though. It quite an interesting vehicle underneath the plastic. Every inch has intent and purpose to it.

 

bump bump bump.

 

you can buy an alternator and have it re-gutted for high output.

 

to sustain 1,000 watts at 12 volts you need an 83 amp alternator. I'm guessing it would draw more than 1,000 watts to output that much. Is this sustained or peak? I don't think you're going to get there on a Fit.

I'd do deep cycle marine gel batteries, an isolation circuit, and aux charger to plug in at night (if you have a place to plug in). Otherwise just drive around to charge it. But not through my neighborhood.

 

lol

Lyon, do you compete or are you just trying to be a mobile earthquake?

 

Well, right now I have a kenwood class d mono sub amp rated at 900 watts rms 1800 peak cea compliant. It's pushing 2 kicker cvrs in my sealed 'winter box' (I switch to a larger ported box in the summer.) I also have a 300 watt rms 600 watt peak cea compliant amp for the 2 Polk mm 6.5 component speakers up front. The sub amp blows 55 amp fuses if I crank it up. At full blast my headlights look more like strobe lights than headlights. No Amount of extra batteries, wires, or capacitors is going to chang that the stock amp only puts out 75 amps and even less at idle. If I could get up to 125 amps and somehow increase idle amps as well I would be very happy.

 

I plug in solar panel charger while I am at work or go out of town. My battery always full and fresh. You can buy it on eBay for ~$20-30.

 

you mention that it puts out less at idle. do you know what the idle output is? i'm in the early stages of planning a system and this would be good to know.

 

Base on 2009 Honda FIT service manual, the alternator has output at 13.5 V at normal engine temperature, 95 A.

 

Yes, actually. Iraggi Alternators recently came out with a HO alternator for 07-08 Fits. Theyre rated at 180 amps. 161 amps @ 900RPMs and 173amps @1000RPMs. But yes the ECU DOES limit the alterantor output to ensure good gas mileage. The stock alternators are not running at full potential until the A/C is turned on. When the A/C is turned on the ECU allows the alternator to put out its maximum Amprage because the car needs the extra amprage for the A/C.

My thoughts on a HO alterantor would be to find the wire(s) that trigger the alternator to put out its maximum out, But not actually having to have the A/C running because that will just rob you of voltage. So i thinks thats my thought on the topic. Im gonna do a little me research in finding out to trigger the alternator to put out its maximum and ill let you know what i come up with.

Ps. Ohio Generators can make an HO alterantor for the fits, but you have to send them your stock one, because they rip the guts out of your stock one and put in better and beefier internals.

 

Why? So there's enough power for the blower motor? Which is also used when the heat/vent are on.

 

Im guessing for the compressor for the AC even though its run by a belt... so beats me. All I know is that the AC triggers the alternator to put out more power. But now that im thinking about it, i better you even if you could trigger the higher output from the alternator, the ECU would limit amprage to 90. So even if you have a 180 i wonder if it would still be limited to 90ish or less.

But i have to say im impressed with the durability of the stock alternator, bc im running 3 MTX 12's with an MTX TE1501D which is 1500watts+ and it slams and MY hids done flicker at all UNLESS the bass hits are super quick and hard. But constand lows and varying bass dont mess with my hids. And im running a 600 watt Orion door speaker amp for my components. But i also got rid of the stock battery and am running 2 Kinetic Batterys.

What are you planning on running that you want to upgrade your alternator?

 

Watching the behavior of the thing, it increases idle speed when you switch on the headlights from about 550 to 800. I also notice that it idles faster for many minutes after starting warm by the same amount. I suspect this is to replenish the battery charge. Normally it loafs at 550 idle, barely enough speed to maintain charge (I think: I haven't thrown a voltmeter on it).

I think when you switch on the A/C it takes advantage of the increased idle speed to increase potential alternator output. But the speed is increased at this time to run the compressor, not because of any extra electrical load (although there is a slight increase to power the compressor clutch, enough to dim the lights until it's able to compensate).

 

Well maybe but the ECU actually limits it untill the AC is turned on for some reason. Im gonna go meter it really quick and ill let you know what happens to the voltage with AC on and off.

 

OK so i just tested my voltage with

AC on fullblast=14.57V
AC off Fan on full=14.54V
AC off Fan off=14.59V

I might just have a higher voltage in general because I replace my stock battery with 2 Kinetic batterys. Kinetics usally rest @13V

IM gonna have to do some more research on the regulater amperage/voltage and how its limited by the ECU. and ill let you guys know what i find.

 

Cool, but watch the idle speed too. I'm curious if I'm imagining things.

 

Hid lights run at a lower wattage than halogen and have a higher tolerance for voltage changes. If you had halogens I'm sure they would be worse.

 

This is good news. Looking back i'm not sure where I got the 75 amp fiqure. I'm going to try a big 3 upgrade and see if I get a better result. I wouldn't have bothered with the big 3 until I had a ho amp but at 1283 potential watts minus enigne/accesory draw it may make a difference.

 

Bumping this up because i'd like to see if anyone has found anything else out. I am at around 2500watts probably 1900 nominal during play and I would love to put an HO alt in my 09 fit. Big 3 is on its way to being done, and I have another battery to add to the car for more help.