To continue my weight reduction, I've been looking into lightweight batteries lately. Have any of you had any experience with certain brands? What brands/models did you use and what were the specs on it? Was this in a 2nd gen rx7, how'd it work out? Did it last well? How much did it weigh?

So far I'm looking at this one http://www.batcap.net/Model800.html

But I've also thought about an Odysey battery because it weighs less and I've found it for cheaper. Not sure how it'd work, though, because it seems to be less powerful.

 

I'd also be interested in this.

 

i saw a member here using a little odysey in his 89 TII that dyno'd at 320rwhp, so it can't be too bad. not sure if he had any stereo equipment or anything though.

 

I have no extra stereo equipment, and will not be putting any in, so I'm not worried about anything like that. The only power draw I will see is the normal stuff.

 

Had an oddysey. COst 125 and is saves alot of weaight. Weighted at 10-14lbs but cant remember.

Batery dies after leaving stereo on for 10 minutes. 80 amp alt not good enoughf for small battery if you have small main and alt pulleys but will work if you dont use stereo.

 

Waste of time - relocate the stock battery will be better


-Ted

 

Use a 51R, optima if you can afford it.

http://cgi.ebay.com/ws/eBayISAPI.dll...088869408&rd=1

I used a 'big' motorcycle battery for a while, light but it didnt last long.

 

i was thinking of doing it.. but is it really worth it?
i know the advantages are better weight distribution and it frees up space in the engine bay.

 

I know of 3rd gen people doing it!...i saw a few people at the lake near me that have one and the guys said they work fine!...Don't forget though that they have the 100amp alt!

 

he could switch over to an fd alt to compensate.

 

what about a relocated little battery? That's what I'm doing. (With an S6 alternator, as well.)

 

When evaluating battery relocation, don't forget to add in the weight of the extra long cables..

 

Why is it a waste of time? Loosing weight = faster car, better handling, and quicker braking. This is just another step in my whole weight reduction process.

I already have an FD alternator so I'm not worried about the power going to the battery and charging it quick enough.

Any idea which model the 3rd gen guys were using? There is an 11 lb Odysey battery I was looking at, but it only has 200 cca iirc. The Odysey that seems best to me is the one with 280 cca I think, but that is still pretty low. And that one weighs 13.5 lbs, at that point I might as well get the BatCap I linked to up above that is 14 lbs and has 800 cca.

 

So are you saying you can use this 10 lbs. or so reduction in weight into a performance advantage?
Sure, theoretically, it's better.
But, can you actually turn that into quick times or shorter stopping distances?
Can I see proof of that?


-Ted

 

Lay off man. It's all the little things that add up, he said it's only a step on his weight reduction, I'm shure it's going to end up being a whole lot more than that...later

 

Oh of course 10 lbs by itself will do nothing, I am not denying that or trying to say it will improve performance in any way alone. But I have been doing a lot of weight reduction and am continuing it. I am doing whatever I can to shave off a pound or so here and there, and let me tell you it really does add up. With a complete interior and a steel hood still, I at about 160 lbs off (still have all emissions too) and after I remove the emissions and finish some other things I'm doing, I am hoping to be up close to 200. Then on my list of things to do is the lightweight battery and an n/a aluminum hood (if available nearby in red) or cough up the cash for the fc3s.org CF hood (farther down the road). My whole plan here was to get rid of as much weight as possible while keeping the car *looking* stock and like a street car (i.e. not removing all the carpet/interior panels).

 

here's the one i'm thinking about:

http://www.portablepower.com/Product...06S1P&AddOn05=

check out that price!

 

Bump

More discussion please

 

what would be better from people who have experience with this to relocate the stock battery to the bin behind the seat or get a light weight battery in the engine bay still

 

also ddub what all did you remove so far and does anyone know the best battery to get if you have a mild system in your car i was thinking the optima red top

 

What you really want in any car is balance. Weight savings is fine and of course every little bit helps but just removing weight isn't the smartest thing to do without working with the suspension at the same time. Relocating your stock battery is a better idea in the sense of balance...you'll be taking significant weight from a corner and placing it in the middle of the car and (hopefully) on the passenger side to offset the drivers weight. We had a dynabat on my GVR4 for a while and were constantly blowing alternators bc the battery was just too weak. We then settled on an optima yellow top and threw it in the trunk mounted to the passenger side of the car. No issues since.

 

Inventory of Weight Reduction In Pounds (Work In Progress) -
AC and AC/PS Mounting Bracket = 36.8
PS = 22.6
Spare Tire/Jack/Etc. = 33.0
Lighter Seats = 10.0
Hatch Belts/Bolts = 1.0
Front/Rear Washer Bottles/Bolts/Brackets = 3.2
AAS Control Unit = 1.2
AAS/Security Light/Side Mirror Adjuster Panel = 0.4
Charcoal Canister = 2.0
Cruise Control Actuator/Control Unit = 3.0
Front Tow Hooks/Bolts = 2.6
Rear Mat = 9.6
Spare Tire Well Mat = 1.0
MOP/Lines/Parts = 1.0
Antenna Stuff = 2.0
Misc. Bolts/Brackets/Etc = 4.0
Storage Bin Carpet/Storage Bins/Bolts = 9.8
TB Mod Parts = 2.6
Actuators/Sleeves/etc For the 5th/6th Ports = 2.0
Various Sound Deadening Mats Etc. = 5.6
Foam Bumper Inserts = 3.4
Some Tar (not all) = 13.2
Front Speakers/Brackets = 3.6
Emissions/Idle (Variable Resistor, Airpump, ACV, BAC,
EGR, Solenoids, Vac Lines, etc.) = 22.6
--------------------------------------------------------------
Total = 196.2

 

My plan is to relocate a lightweight battery to the storage bin area, it will provide weight savings and better balance. This is the battery I'm looking at:


http://www.batcap.net/Model800.html

 

is it a regular or gel type? a couple of things i about batteries are CCA (cold cranking amps) and RC (reserve capacity). these are all important and you should find some with higher numbers (than "typical" batteries that you have/have used). i believe the yellow optima has some very impressive numbers and is a gel type. these batteries (gel type) are also _much_ less affected by cold starts.

Cold Cranking Rating: "...determined by load, in amperes, a battery is able to deliver for 30 seconds at 0F (-17.7C) without terminal voltage falling below 7.2volts for a 12-volt battery. The cold cranking rating is given in total amperage and is identified as 300 CCA, 400, 500, and so on. Some are rated as high as 1100 CCA."

Reserve Capacity: "...determined by the length of time, in minutes, that a fully charged battery can be discharged at 25 amperes before battery voltage drops below 10.5volts. This rating gives an indication of how long a vehicle can be driven, with the headlights on, if the charging system were to fail."

there's also Ampere-Hour Rating and Watt-Hour Rating. let me know if you want their definitions, too. also, if you care to know the advantages of Recombination batteries, aka dry-cell or gel-type.

 

Yah I have a Yellowtop optima gel battery in my Ford Escape with a huge system, upraged alternator and 5.0 ferrad cap, it works super good

Yellowtop should be plenty for your system, I'm pretty sure a Redtop would be good too.