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jstein77
jstein77 Dork
2/28/13 12:11 p.m.
mazdeuce wrote: and a sub 2 lb lithium battery for $60....

How did you get a 2 lb battery for $60? I paid $150 for a 15 lb Braille.

mazdeuce
mazdeuce Dork
2/28/13 1:51 p.m.
J308 wrote: Wow good thread. I'm jealous of the budget though. I haven't mustered the courage to propose my $50/week budget, INCLUDING car, to SWMBO.

I won't deny it, my life is awesome. 10 years ago when my second kid was born we looked at the budget and realized that we couldn't hardly afford $50 a month. That's when I quit autocrossing for a number of years. It's much less stressful when you're not checking the couch cushions for change to get together enough for the entry fee.

FSP_ZX2
FSP_ZX2 Dork
2/28/13 1:53 p.m.
jstein77 wrote:
mazdeuce wrote: and a sub 2 lb lithium battery for $60....
How did you get a 2 lb battery for $60? I paid $150 for a 15 lb Braille.

I paid about $30 for a #10 pound lawn mower battery at Wally World.

mazdeuce
mazdeuce Dork
2/28/13 2:00 p.m.
jstein77 wrote:
mazdeuce wrote: and a sub 2 lb lithium battery for $60....
How did you get a 2 lb battery for $60? I paid $150 for a 15 lb Braille.

Ok, this is why I need to update the thread, otherwise I'm just a lazy bastard.
A couple of months ago there was a thread about lightweight batteries. Someone suggested the Zippy LiFe batteries from hobbyking.com and gave some rules of thumb to make sure you got the right voltage and enough amperage and what not. The battery was only $39 but then I bought some connectors and the battery was shipped from Hong Kong so that was another $15 and then there was a CC fee so in the end it was right about $60.
I just got off my butt and hooked things up for a trial run. The car started right up. Sat and idled perfectly for 20 minutes. The headlights work and I can roll all of the windows up and down at once with not noticeable effects. The battery didn't get warm at all. I've got to pick up some solder to secure the connectors that I'm using and then I'll properly mount it with zip ties and run it for a while and let all of you know if I blow up or not. Coke can for scale. It's a small battery. I just checked and Hobby King says it weighs 558 grams. That's 1.23 lbs.

Winston
Winston Reader
2/28/13 2:12 p.m.

That is seriously cool. I'm curious about the longevity of a setup like this. It seems perfect for autocross/rallycross runs.

mazdeuce
mazdeuce Dork
2/28/13 2:17 p.m.

I am also curious about the longevity. My plan is to hook it up at home and then autocross/rallycross on it for the day and then re-install the regular batter for day to day stuff. For the first little while I'll be carrying the stock battery and a fire extinguisher with me. If it works, I don't think there's a cheaper easier way to shed 25 lbs off the front of the car.

mazdeuce
mazdeuce Dork
2/28/13 2:30 p.m.

The other thing I did recently was put longer ARP wheel studs in the front of the car. This stemmed from another thread on the board where I asked if I was going to die if I used my super cool Blox aluminum lug nuts. The popular opinion was that I was not going to die, but more thread engagement was better. I little measuring and testing led me to believe that the stock lugs would engage something like 13 out of 21 of the threads on the aluminum nuts. What I decided to do was purchase and install longer studs in front, mostly because I knew the part number for those, and run the aluminum lug nuts on stock studs on the rear and long ones on the front and see what happens.
Installing the studs is easy. Take off the wheel, the caliper (hang it to the side) and the brake disk. The studs just hammer out. However, if you just hammer them then you're likely to mush the threads on the end and make them useless. At least I did. If you put a piece of steel between the stud and the hammer, they come out pretty.

I don't know why I want to preserve the studs, but it seems foolish to break parts if I don't have to. The studs slide out through this conveniently placed hole in the dust shield right next to the ABS sensor.

They go back in the same way and are pulled into place with a stack of washers and a backwards lug nut.

mazdeuce
mazdeuce Dork
2/28/13 2:36 p.m.

To compare, here is a stock lug next to the new shiny gold one. The nut is screwed down to where it sits when tight on a stock wheel. More threads equals more awesome.

I put a coat of anti sieze on the hub before putting the rotor back on because stuck rotors suck. I also used anti seize on the studs because aluminum nuts on steel lugs make it seem like a good idea. There's probably lots to argue about that, but it's what I'm doing.

Since I taking stuff apart I took the rear drum off to have a look see. Remember to release the parking brake before trying to take off the drum. Not my proudest moment. The studs in the rear are different. They have a smaller shoulder and a smaller knurl. I'm pretty sure that they're the same size as the smaller Miata ones, but I need to knock one out and measure to be sure.

bgkast
bgkast Reader
2/28/13 3:16 p.m.

I use those Zippys in model airplanes. I would be careful of it, Li-POs are sensitive about overcharging and catch fire when un-happy. You at least probably want to get a cell balancer to plug into the second pig tail. Something like this: http://www.readyheli.com/BLINKY-Astro-Blinky-Balancer_p_32209.html

Adrian_Thompson
Adrian_Thompson UltraDork
2/28/13 3:24 p.m.
J308 wrote: Wow good thread. I'm jealous of the budget though. I haven't mustered the courage to propose my $50/week budget, INCLUDING car, to SWMBO.

I had a hard time getting a $25/month past SWMBO, the rest comes from selling old stuff.

mazdeuce
mazdeuce Dork
2/28/13 3:30 p.m.
bgkast wrote: I use those Zippys in model airplanes. I would be careful of it, Li-POs are sensitive about overcharging and catch fire when un-happy. You at least probably want to get a cell balancer to plug into the second pig tail. Something like this: http://www.readyheli.com/BLINKY-Astro-Blinky-Balancer_p_32209.html

It's a LiFe. I read somewhere that they behave better than the LiPO batteries and are less likely to catch fire. I'm still trying to decide how I feel about the phrase "less likely to catch fire".

J308
J308 Reader
3/1/13 3:24 a.m.

In reply to Adrian_Thompson:

$25 / Mo. Including the cost of the actual car? Or did you already have that?

I casually mentioned another car last night and received no comment. Doesn't lack of rejection constitute permission?

Adrian_Thompson
Adrian_Thompson UltraDork
3/1/13 7:07 a.m.
J308 wrote: In reply to Adrian_Thompson: $25 / Mo. Including the cost of the actual car? Or did you already have that? I casually mentioned another car last night and received no comment. Doesn't lack of rejection constitute permission?

Nope, that's what comes from the family budget, every other cent comes from selling parts from previous projects right now. Luckily I had a large stash of parts sitting in the basement for the last 15 years. So far it's netted me over a grand which has allowed me to buy the SAAB and parts needed to date. I'm hoping the birthday bunny will buy me some Bilsteins next month though. I have a friend who sold some crappy Kia or Hyundai thing recently and I think he still cas some snow tires I might get cheap for rallycross.

mazdeuce
mazdeuce Dork
3/4/13 1:38 p.m.

Just a very quick note to mention that the battery worked flawlessly all weekend. Driving the kids back and forth to things and then autocrossing. It even started the car without a hitch at 31 degrees in the morning. It's like magic. It's hard to say if taking 25 lbs off the heavy front corner of the car made any difference, as I had 150-200 lbs of passenger in my car for all of my autocross runs.

pres589
pres589 SuperDork
3/4/13 1:45 p.m.

I'd be very curious about the charge circuit and controls in place to ensure the battery doesn't see an over-voltage and start out-gassing and such (read: fire). The price is great, the weight is great, but they don't like extreme cold, and again, fire.

Winston
Winston Reader
3/4/13 2:00 p.m.

Looks like you're having great results with it!

I do wonder about fire myself. I found this... not sure if relevant:

LiFePO4 battery-powered car catches fire

mazdeuce
mazdeuce Dork
3/4/13 2:26 p.m.

Right now I'm relying on the fact that I have a very modern car to protect me against overcharge. My assumption is that the computer on my car is already paying attention to the charging of the battery and if something goes pear shaped then it will tell me. Feel free to correct me if I'm wrong. I guess the question is whether or not it will let me know before things light on fire. Everything I read says that you have to abuse the ever living E36 M3 out of a LiFe battery to get it to melt down. Additionally, these batteries are built 'soft' for lack of a better term. If they swell, there is nothing to really hold them together and build the pressure necessary for an explosion. They'll just swell and tear the shrink wrap on the outside of them and fall apart. As far as cold goes, 31 the other morning is about as cold as it gets here in Houston. You northerners will have to sort it out yourselves.
I'm watching things closely and I have a fire extinguisher in the car.

Winston
Winston Reader
3/4/13 2:57 p.m.

My concern would be whether the overcharge protection built into the car for a lead-acid battery translates to a LiFe battery. Electronics is not my strong suit, so that may be a non-issue.

At any rate, I think you're far better off than an EV since you are with the car when the battery is charging. For an extra layer of safety, you could mount a temperature sensor to the surface of the battery and run it to a display in the cabin... if you were so inclined.

mazdeuce
mazdeuce Dork
3/20/13 2:23 p.m.

Ok, my last budget was $375 but that was two and half weeks ago. I'm going to give myself $300 to get me current to the end of this week which is the 24th. Then I'm going to take away $15 for the TAMSCC autocross last weekend. Very cool event. It's at the site where the national tour is this coming weekend. Simply huge concrete ex-runway. Giant course. Cheap. Laid back group. Awesome. I also ordered a full sticker package from Mazda so that I will be eligible for contingency money this weekend. That's another $32 down. So that's $628 in the budget, which is good. The sad news is that I think I'm going to have to start subtracting from this budget for the Porsche too, at least for now. So we'll take away the $379 that I've spend ordering stuff from Pelican and the $43 that I sent to Australia to get new keys and now I'm down to $206. I think I missed a few things that I bought locally for the Porsche but we'll just sweep those under the rug. $206 it is.
In other news, the 2 developed it's first real rattle. It took me about a week to figure out that it was the sun visor clip right over my head. This little guy.

I pulled it out and put a few little pieces of command strips between the metal and the clip like so, and it's quiet as a mouse.

The last thing I had to do was make even more class letters for the rallycross this weekend. It's an SCCA National Challenge event and they're being quite strict about rules interpretation. I'm in very slight violation of stock class rules, nothing that actually makes me faster, but I don't want to switch out the motor mount and take out the camber bolts and re-align the car. I'm lazy. The camber bolts are the interesting thing. They're not legal in stock. Check. It turns out that they're probably not legal in prepared either. The rules for camber adjustment in prepared for strut cars very specifically says that adjustments are to be at the top of the strut. Technically I should then be moved to modified. I don't really care to be honest, I just want to go drive in the dirt. Since I'm not sure if I'm going to be in PF or MF I made a P's and M's. Whichever class it ends up being, this will be the seventh class that I've raced the car in.

fidelity101
fidelity101 HalfDork
3/21/13 8:20 a.m.

In reply to mazdeuce:

My old roommate and I always talked about this idea, he was big into remote control helicopters. We never actually tried it though.

mazdeuce
mazdeuce Dork
3/21/13 11:37 a.m.

I read a lot of speculation and a few that said they had done it but not a lot of real world "this works and this is how I did it" stuff. I'm trying to document it so that the next guy who speculates can do a search and find out how it's been done if he wants to try.

mazdeuce
mazdeuce Dork
3/22/13 7:50 p.m.

Because contingency.
The car is packed for the Rallycross National Challenge. I begged Winston to co drive and he graciously accepted. I've joined the Mazda Racing thing to see if I can't collect some contingency money. Putting the stickers on magnets and cutting them out suuuuuked. Further reporting after the weekend.

mazdeuce
mazdeuce Dork
3/24/13 8:11 p.m.

Fun weekend for the 2. The SCCA decided to run their first ever Texas National Challenge Rallycross in the giant fields in front of Texas World Speedway in College Station Texas. We were about half an hour south of the Solo National Tour event that was also this weekend. It was a two day event with eight runs on Saturday and four runs on Sunday.
Before the event I tried hard to fill the co-driver seat on my car. I must have asked five different people at the last few autocrosses and a few days before the event I had not takers. I decided to send Winston from the GRM board a message to see if he was busy this weekend. I hadn't ever met him in person, but he is local and is building a Miata powered Triumph in his garage and that's a good enough resume for me. He agreed to take the seat and we met in the early morning hours on Saturday.

We had a good first day of driving. There were six cars of various persuasions in PF with us ranging from a stock rental Yaris on snow tires to a well prepped CRX on rally tires with a LSD, amongst other things. This was my first event to use my newly minted SCCA Safety Steward credentials so I spent a fair part of the day dealing with the safety aspect of course degradation. Between the driving, the course changes, and trying to do what I could to help things move along it was a long day. Without giving you the blow by blow, I finished the day second in class, a fair bit behind the CRX but only 1.5 seconds ahead of the very well driven Yaris.
Sunday morning broke way too early and we were back at it. Knowing that I had a very narrow lead I had a hard time committing to really pitching the car down course. Fast would be good, too fast would be bad, it was a hard line to walk. After three runs I was down on time and I knew it. There was one section of the course that I suspected I could take without lifting but it was scary. I eased through it my first three runs but gave it all I had on the fourth. It worked but barely. In the last kink I was up on two wheels and only just managed to bring it down and through the finish gate without pooping myself. When it was all said and done that last hero run gave me second place by 0.3 seconds. A second place in PF was enough to get me a National Challenge trophy and some contingency money from Mazda. Winston drove my car great. I think the only reason I was ahead of him was because he spent the first half dozen runs getting used to things. After that we were pretty much swapping fast time. He's a good co-driver. He gridded the car when was doing my safety duties, he helped change tires, he didn't break anything, and he let me win. He is also one heck of a friendly guy.
An interesting side note to the weekend. With the rallycross and the solo tour going on at the same time, most of us had to choose one or the other. Brianne Corn, who is a solo national champion, a rallycross national champion, and a Pikes Peak winner didn't. She managed her work assignments between the two venues to allow her to run both events. At the solo tour she picked up first in B-Mod and FDT, and at the Rallycross National Challenge she picked up first in MA and FTD on every course. To the best of anyone's knowledge, this is the first time anyone has won two national tour events on the same weekend. It was quite an accomplishment.

pres589
pres589 SuperDork
3/24/13 8:19 p.m.
mazdeuce wrote: Right now I'm relying on the fact that I have a very modern car to protect me against overcharge. My assumption is that the computer on my car is already paying attention to the charging of the battery and if something goes pear shaped then it will tell me.

I don't like to lecture, and it isn't my department... I work at an aircraft company and we have some experience with lithium ion batteries (not a company that's recently had a new model grounded, someone else). I've not been directly assigned to deal with these batteries, but I sit next to a guy who does and he's teased constantly about how many aircraft his pet battery projects are going to burn to the ground.

There's charge and discharge monitoring that is special to these batteries vs. the standard NiCad. We don't have a lead-acid option on the aircraft I'm working but same idea; you can't just swap these and assume "the computer" will know exactly how to deal with these things. The modern alternator system on a car is pretty decent, I believe, but aircraft are also pretty good in this department and it's rate of inflow and outflow, I believe, that makes these things heat up so much. Again, not my area, but this is my basic understanding so grain of salt with this.

Here's something you could keep handy; http://en.wikipedia.org/wiki/Fire_extinguisher#Class_D Something else smart might be a remote temp monitor of some sort to keep an eye on the battery while in the driver's seat. See it go crazy, time to start worrying. I don't know of a better way to monitor this stuff.

Do what you want, just something I saw and am thinking about, I'm pretty excited to think that the common guy could get a nice light & powerful Li-Ion battery in his car. So one more reason that I'm watching this thread.

mazdeuce
mazdeuce Dork
3/24/13 8:34 p.m.

I've been carrying a fire extinguisher in my car when I'm running the battery. I'm also concerned that something bad could happen. I'm also aware that nothing bad might happen. I'm driving the car and monitoring things and I'll see how it goes. Like you, I want to know if this actually works and sometimes all you can do is research, prepare, and jump in with both feet. I ran the battery all weekend without any drama. 24 rallycross runs, lots of shutoffs and starts and driving back and forth to the venue. The battery was never even warm to the touch. I did pull it out when I got home tonight and I'm back to my stock battery.

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