Has anyone here actually weighed their vehicle?

[bmw m3 s50]

I think this battery might be fine for your use case. Bracket is 9.1 oz according to their website. Don’t remember how much the aluminum plate weighs, but def not more than a few oz lol. IIRC the overall weight of the battery, bracket, and plate was around 7 lbs, and the weight loss was -47 lbs. Really good weight reduction mod IMO. If you decide you want a more plug and play solution, you could get the Antigravity H6 battery and reuse the OE bracket. I’ve seen a couple of used ones on Rennlist.

My OE CSL trunk was the most disappointing mod in terms of weight reduction, but perfect fitment and not having to deal with adjusting it makes up for that I guess lol.

Edit: I just checked my notes, and it looks like when my car was a gutted track car it weighed in at 3060 lbs without driver and fuel. I’m guessing the car weighs 3150-3200ish dry, now that it’s a street car with full interior.

I am thinking the ATX30-HD is the way to go with that 9.1oz bracket. Especially, for my use of the car. The battery is pretty affordable too at $600-$650 compared to some of the H6 battery at closer to $1000

Yeah, that OEM CSL trunk is looking pretty disappointing. I though there would have been weight savings over the OEM trunk.

I would be really happy at 3050lbs but thinking I will probably end up around - 3150lbs when it is all set and done.

[bmw m3 s50]

The factory battery weighed 49lbs in my car, so you may not get 40-50lb weight savings. My lithium battery is 19lb for a 30lb weight savings, for example.

The ATX30-HD weights in about 8lbs coupled with the bracket just under a pound so let's make a total of 9lbs for battery and bracket - that's 40lbs reduction if the stock battery weights 49lbs.

[bmw m3 s50]

Sheet is attached to the post (had to edit to make it show for some reason), and as stated it is accurate for an M3 as the only material difference is front and rear track width. I have a touring, but the numbers don’t care which body you are running

For some reason the spreadsheet is showing as a picture and not editable.

[bmw m3 s50]

Latch is the child seat anchors. It's not that much weight :P

Sound quality with two speakers, powered by the head unit amp, isn't amazing. That said... I almost entirely listen to podcasts, and it's plenty good for that. I didn't do a write up, but... it is what it is. Remove everything, install what you're using. The chassis to stereo harness plug is right behind the head unit, so you can get power/ground/ibus there, and then just connect the speakers to the head unit and.... done. The PITA part of the project is pulling the entire interior and all the wiring.

Ugh, yeah pulling the entire interior out is probably not happening. I will probably have to find, other ways to start getting a couple pounds here and a couple pounds there, so that it starts adding up. I do plan on pulling the bottom seat cushion out and the rear section carpet out so that should give another 20lbs hopefully.

[bmw m3 s50]

Full tank. Lithium battery is worth another 40-50 pounds so you aren’t too far off. Within a reasonable margin of error for sure on the scale.

Also my “lightweight” 19 lb wheels with Hankook RS4 brick tires felt pretty much as heavy as my ZCPs with lighter Michelin PS4S .. could be a nonzero factor if you have heavy tires

So with the Antigravity Battery, I will be around the 3295-3300 lbs mark with a full tank. With a half tank, I will be at the 3245-3250lbs mark. Honestly, hoping I can find a shop to fabricate a quiet titanium muffler to save another 30-35lbs off the car. Coupled with a Karb CSL trunk, should be at the 3200lbs mark with a half tank of gas.

[M3dragon]

simple way to lose weight. Don't be in the car =P

[Obioban]

I can't find the article now, but I once read something where the founder of Spoon Sports was talking about his philosophy of modifying cars, and he was explaining how their goal is to reduce weight by just a tiny bit, but on all their products, as weight adds up. So you lose a pound on one part, but if you do that over 100 parts, you'll end up going way faster.

Same concept here, instead of trying to find large items to remove and lose weight, just try to shave weight everywhere. It will add up.

100% this. Consider weight every time you do something to the car. Everything matters.

[9kracing]

I can't find the article now, but I once read something where the founder of Spoon Sports was talking about his philosophy of modifying cars, and he was explaining how their goal is to reduce weight by just a tiny bit, but on all their products, as weight adds up. So you lose a pound on one part, but if you do that over 100 parts, you'll end up going way faster.

Same concept here, instead of trying to find large items to remove and lose weight, just try to shave weight everywhere. It will add up.

[Bry5on]

$11k for an aluminum block. 40-50lbs off the front axle

[dHam_Slow.46M]

Since we're on the topic of composites, we shouldn't forget that Karb makes some CF body panels. $10k for ~11kg(24lb) shaving🤪

[Gt4]

I also sell CF cabin filter housings 7.5lbs lighter

And I am working on a lighyweight shock mounts alternative for our CSL bumper with aluminum rebar version. Total assembly will be lighter than the kevlar rebar option

[Gt4]

You can also read this thread:

https://nam3forum.com/forums/forum/main-forum/e46-2001-2006/275790-altaran-s-weight-reduction-journey

[bigjae46]

I don't think getting close to 3000lbs with a half cage is feasible unless you add a combination of noise, rattles, and discomfort. But did you pull the stereo harness out? That's a couple of lbs.

And that's the key, you have to look for a lb here and there. Then you're looking for ounces. People say that 8oz won't make a difference. Yeah, but find 20 of them...that's 10lbs.

To get under 3000lbs, you need to give up comforts like windows that work, power door locks, and heat. Does that thing need 4 bolts holding it? Will 2 work? The rear bumper reinforcement has 3 nuts on each side...I removed 1 from each side. If you really want to make the car light - need to dust off the sawzall and remove sheet metal. I got the car to 2610lbs with a full cage and no fuel without a strand of carbon.

Composites...it is also a compromise. A carbon part with OEM like function is not going to save a lot of weight especially if the part is aluminum. A carbon hood will only be a couple of lbs lighter. You can pull off more weight but it could flutter at higher speeds.

[SQ13]

Wow, so you definitely have alot of electronics still hooked up. I glad to hear that the battery has been holding up.

I plan on having the battery hooked up to a battery tender the entire time the car is in the garage. When the is used it will be driven then put back into the garage. It will never be a daily driven car.

Thank you for posting that tie down option. I have been looking for something to help with the tie down of that battery.

How much did that bracket weight?

I think this battery might be fine for your use case. Bracket is 9.1 oz according to their website. Don’t remember how much the aluminum plate weighs, but def not more than a few oz lol. IIRC the overall weight of the battery, bracket, and plate was around 7 lbs, and the weight loss was -47 lbs. Really good weight reduction mod IMO. If you decide you want a more plug and play solution, you could get the Antigravity H6 battery and reuse the OE bracket. I’ve seen a couple of used ones on Rennlist.

My OE CSL trunk was the most disappointing mod in terms of weight reduction, but perfect fitment and not having to deal with adjusting it makes up for that I guess lol.

Edit: I just checked my notes, and it looks like when my car was a gutted track car it weighed in at 3060 lbs without driver and fuel. I’m guessing the car weighs 3150-3200ish dry, now that it’s a street car with full interior.

[Bry5on]

The Braile GU1R I've been running for the last 11 years is 6 lbs.

As I understand it that’s about as small as you can go. I’d ballpark it at 30-40lb reduction for estimations. Sounds pedantic but since we’re all counting pounds here…!