ToothDoc

I'm trying to make something that can actually exceed the OEM performance and still be significantly lighter. A Fit battery will have a difficult time starting a 5.0 V8 when it's really cold outside - especially after a couple of years. If all goes as planned, a LiFePO4 battery should outlive the car.

ToothDoc

So continuing this project, if I discharge my lead acid battery completely, the sulfuric acid will simply turn into water. Then I can drill a hole in my Panasonic car battery (the OEM one) and drain out all the water (I'll have some baking soda just in case) and then take the battery apart, take all the plates out and use the battery so I can remount everything back into the OEM case. Then I'll probably double the capacity so I have 10 packs of 4 cells so it'll be 23 amp hour pack - roughly 1/2 the capacity of a stock battery but it'll do 600 CONTINUOUS amps and more like 800-900 CCA (according to the battery testing device). In the end, it'll be "stock" but only about 10 pounds and should last a lifetime and it'll fit into the stock tray with no modifications.

I'll continue to post updates as we go along - but for now, I plan on really pushing the 4 pound pack and seeing how many days it can go w/o charging. See how cold it can get before it won't start. Suggestions and comments welcome. BTW, if anybody is really interested, I'd gladly get into more detail about charging, where I got the parts, what kind of soldering iron, connectors, etc.

Joe Z

iTrader: (10)

^^ I think there are holes under the battery label if I remember correctly..

I will take a look later.. So maybe you won't have to drill out holes to drain.

Nice progress on the project so far..

Joe Z

ToothDoc

I didn't drive the car again today and it measured 13.05 volts. But now, I have a better idea. Tomorrow, I'll hook up a "watt meter" to the car to see what the actual energy draw of the IS-F is when it is just sitting there. I'll monitor energy usage in a 24 hour period and that way, we can calculate/figure instead of me waiting a week+ w/o using the car. LOL

EyeKutr

iTrader: (5)

Dude, you are incredible...

Lets Drive

iTrader: (3)

This comes along as I moved my PC680 battery from my 7 to the IS, while bouncing some emails to voltphreaks, which is who I thought you were refering to with the 3.5lb battery. The first thing I wondered, was how you planned to get that to start the F's V8, reliably.

Creative ways to shed mass are always appreciated. Very nice work, Toothdoc.

ToothDoc

So far, I haven't even turned the car on since I installed it (19th) - which was 5 days ago. I've just been monitoring the voltage to see if it starts to dump. So far, yesterday it was 13.05 and day before that was 13.05 and today is 13.04 volts. These batteries have a 50% charge at 12.8-12.9 volts so I'm still above 50% charge. When I did start it up, it actually had NO problems whatsoever at starting - I think it might even turn over a tad quicker since there is less voltage drop over load than the lead acid battery.

I had removed the OEM rims today and put the 18" winter fronts (44 pounds each). The stock 19" PS2 are 47 pounds each up front. So, that's another 6 pounds. I also removed the rear PS2s (51 pounds) and replaced it with the drag tires and rims - about 43 pounds.

So, if anybody is keeping track, that's 40 pounds of battery, 40 pounds of spare and jack and plastic, and about 20 pounds of wheels/rims. Last year, I had lighter tires on (1/2 bald 18" tires from my IS350). So, I'm running about 100 lbs lighter than stock.

I think I'll go for a quick cruise to make sure I put the wheels on right. I'll video the first startup since 5 days ago...

caymandive

iTrader: (2)

Best mod for this car is weight loss and you are doing an excellent job at it! I also notice you are not only putting the car on a diet, but you've been doing a great job on yourself too.

ToothDoc

So, I just cranked it up and NO problems. It started right up and it is still 13.05 volts after shutting it down. In addition, I also remembered why I don't like the ET streets. They have TOO much traction. I turned off all traction control and it's only 60 degrees F tonight and no matter what, I can't get them to spin on the street. Trust me, the PS2's would've been TOAST tonight. LOL, I went to gas up with 100 octane but they were out. I wanted to see if 100 octane made any difference.

Anyways, it got me thinking - the battery should've been topped off a bit after driving a few miles but it didn't. I wonder if there is a charge monitor of sorts in the car and it doesn't charge the battery unless the voltage falls below a certain point. So far, it appears that the batteries have only supplied energy to start and keep the other electronics running while the car is off. I guess I'll keep on driving and keep on monitoring the voltage of the pack at this point.

RX469

iTrader: (1)

I was just reading about those very same batteries yesterday.

Nice job! Weight loss is great!

Joe Z

iTrader: (10)

I might be better to do a mix to achieve 93-94 Octane..

Lobux has a formula..

But I think its approx. 3.8 gallons of 100 octane and the rest topped off with 91 Octane..
(on a full empty tank)

In Cali, we get screwed with 91 Octane, as the highest available Premium Fuel.

Good Work So far!!!

Joe Z

Joe Z

iTrader: (10)

I agree with you!!!


I just shaved a solid 22 lbs, by ditching the OEM suspension for a Full Coilover Set Up!!!

Joe Z

TWong350

iTrader: (8)

Wow...very innovative. Great work!

ToothDoc

Nah, not quite innovative - Volt Phreaks already had this made/done but at $1300 a battery, it didn't make too much sense. Their batteries have a low voltage cutoff and an overcharge protection mechanism. BUT, at least in our Fs, the voltage regulator is 13.75 volts so it can't overcharge and as long as you drive your car at least once every couple of weeks, it won't overdischarge - at least that's my hope.

caymandive

iTrader: (2)

22lbs weight savings with the new suspension!????