Alternator bypass & engine preheater mod

[California98Civic]

Originally Posted by paulgato

But California98Civic, I'm still getting contradictory advice from Enersys tech people about the proper charging current for Odyssey batteries, and whether this minimum 0.4C charge they talk about is really necessary or not. What did you conclude about that?

Sorry that I missed this post and left you hanging. I concluded that i needed the higher amp charger for the sake of the battery longevity and function. My battery is rated about 40 amp hours and I got their 25 amp charger. As you learned, the theory is that you get throuh the bulk charging phase fast enough that there is lots of time fo the float charge. More time apparently means better battery condition long term. I have had this set up for maybe two years now without any problems. I drive a 11-14 mile comute each day, charging only at home, sometimes using the alt to extend range. Sometimes i charge at work (free) too. I never let the battery too-deeply discharge.

[ctgottapee]

Have you guys altered your music listening, like switched radio decks or no music, or ipod in passenger seat?

That appears to be my biggest use of juice while in motion. (also while resting)
Unless I run the fan as it's resistor based.....
I've got my headlights down to 40w at night.
After market manufacturers don't generally publish specs on this.

[oldtamiyaphile]

Originally Posted by ctgottapee

Have you guys altered your music listening, like switched radio decks or no music, or ipod in passenger seat?

In my Skyline it's Andoird MP3 only, but that's for weight savings and the fact that the original radio was stolen before I bought the car.

For my other cars, they've all got Kenwood KIV-701 mechless headunits. By not having CD players they're around 500grams lighter than OE and no spinning motor saves a few mah too (possibly offset by the colour TFT screen).

Consider how long an 80's boom box ran on just a bunch of D cells. Not much drain comes from music unless you've got a lot of subs.

[California98Civic]

I took the six CD changer and it's cage out of the trunk. I installed an aftermarket aux jack to play mp3s through the stereo. I don't use the back speakers. I frequently just listen to mp3s on my tablet, placed on the dash, with sound reflecting back at me off the windshield. But at moderate volume the stereo is not a big power draw. Not like the headlights.

[ctgottapee]

I'm guessing you measured correct.

My stereo is the largest wattage use outside of the fan.
Headlights are down to 40watts, the stereo jumps around but is 25-110w with some larger peaks. 25w is when its off with car running - appears to be a bit wasteful, but not really in the realm of things for an auto. The always hot line to it has a 2amp fuse so 25w is about right.

Still hooked to four speakers, prob try disconnecting the rears.

[oldtamiyaphile]

Dude, just go on eBay and get a new MP3 brand name stereo for $60 already. It'll draw 20mah standby and a lot less than 110W when pumping.

[paulgato]

Originally Posted by ctgottapee

Have you guys altered your music listening, like switched radio decks or no music, or ipod in passenger seat?

That appears to be my biggest use of juice while in motion. (also while resting)
Unless I run the fan as it's resistor based.....
I've got my headlights down to 40w at night.
After market manufacturers don't generally publish specs on this.

I only use radio really. That suits me fine these days. The radio use about one amp, and I'm usually happy to spend an amp (13w?) on that luxury. On a long journey where I want to absolutely minimise ampere spend then I might use the radio on my mobile phone with headphones.

I could also use an mp3 player with headphones (actually an old i-phone which I also use for internet radio) but I rarely bother.

I used to use over-the-ear headphones years ago when I drove a noisy van, to protect my ears. If you can cut out background noise with headphones then you don't need such high volume to hear the music properly, plus it just plain sounds better. I built in a headphone socket and a speaker-kill switch in the dash from the car's hifi.

[paulgato]

Originally Posted by California98Civic

Sorry that I missed this post and left you hanging. I concluded that i needed the higher amp charger for the sake of the battery longevity and function. My battery is rated about 40 amp hours and I got their 25 amp charger. As you learned, the theory is that you get throuh the bulk charging phase fast enough that there is lots of time fo the float charge. More time apparently means better battery condition long term. I have had this set up for maybe two years now without any problems. I drive a 11-14 mile comute each day, charging only at home, sometimes using the alt to extend range. Sometimes i charge at work (free) too. I never let the battery too-deeply discharge.

I think in the end I AM going to try to get a larger charger than my 10A one. It's rated 10A. but I have a suspicion that although it starts at 10A it quickly slows down to about 7A as it heats up (fanless waterproof model). Also, I think it's POSSIBLE that the higher amps actually help the Odyssey battery life in itself, quite apart from just reducing the time to charge 100%. (Helps to 'drive the charge into the battery' or something?)

In any case I found a 40A marine charger...

Pro Charge Ultra - Global PFC NEW*

...which has 3 outputs and which I can use for charging both my 'battery banks'. It has a fully adjustable output voltage AND current, so if I find any better information or change my set-up later on I can change the charge regime wihout having to change chargers. It even has a LiFePo4 setting. I haven't bought the charger yet - got to check I have space to install it somewhere, but it looks ideal.

[California98Civic]

Originally Posted by paulgato

I haven't bought the charger yet - got to check I have space to install it somewhere, but it looks ideal.

Sounds like a great charger. Gives you more future potential as you play with new ideas. I went for the 25 amp one because it had a lot of good features, but also because it was the largest that I could inconspicuously install under/behind the driver seat. I always have it with the car, which means I can plug in anywhere about as conveniently as possible (at a buddy's house in the next county, at work...).

[paulgato]

Originally Posted by California98Civic

Sounds like a great charger. Gives you more future potential as you play with new ideas. I went for the 25 amp one because it had a lot of good features, but also because it was the largest that I could inconspicuously install under/behind the driver seat. I always have it with the car, which means I can plug in anywhere about as conveniently as possible (at a buddy's house in the next county, at work...).

Yes, this marine charger is designed to be installed on a vertical surface. I have a bumper plug/socket that came with the coolant heater, so plugging in at other places is just a matter of carrying a spare cable.

The only place in the vehicle I found to permanently install a charger is in the load area at the side, right at the back, behind the rear wheel arch, where there is an access hatch and a small storage cubby-hole. That space was just big enough for a footpump and an emergency warning triangle. I'd have to hack/remove the inner plastic moulding in that cubby-hole, but the space is ventilated, and just about big enough for the charger.

But, being a triple output charger, it should be the only charger I need, which is good because there really isn't any other space in the cabin to fit a charger of any size/heat dissipation at all. Under a seat is OK but i'd be really worried about cables being snagged when someone sldies the seat back or forward. Plenty of space in the spare wheel well of course, but I'm told it's not a good idea to have the charger in the same small, poorly-ventilated compartment as the battery.