1M Weight Thread

[Dan Parker]

Removing the back seat and any sound deadening under the carpet is equivalent to about 3-4 gallons of petrol.

[Whteverjklasdf]

4 gallon of petrol is about 15kg. not too bad to begin with. =P

[mPlasticDesign]

Originally Posted by Sealobo

4 gallon of petrol is about 15kg. not too bad to begin with. =P

Maybe a bit high in the conversion. More like 11.3kg's

I believe @ 72 degrees F was around ~6.2lbs per gallon

[Whteverjklasdf]

i thought one gallon is about 3.79 litre?

[Dan Parker]

There's an app for this....

[mPlasticDesign]

Originally Posted by Sealobo

i thought one gallon is about 3.79 litre?

It is, but you were talking about weight in kg's. So you have to establish a temp which I did and then convert.....

Originally Posted by Mr.Metak2you

...I believe @ 72 degrees F was around ~6.2lbs per gallon

So 4 gallons X 6.2lbs = 24.8lbs

24.8lbs = 11.3kg
2.2lbs/kg

[Whteverjklasdf]

i don't know... i assumed 1 litre of petrol is roughly 1kg...!

[mPlasticDesign]

Originally Posted by Sealobo

i don't know... i assumed 1 litre of petrol is roughly 1kg...!

Actually, I just did a quick calc and got 3.6litre/1kg. Anyone want to double check that?

6.2lbs X 2.2kg X 1gal = 3.6litre/1kg
1gal x 1lbs x 3.79litre

[gmx]

2020's era bump.

I have seen numbers for stock seats as:
54lbs (manual), +15lbs to electric.
34kg (pp1 of this thread) electric seats.

I measured 28.1kg ea for electric seats with memory, go figure. I did not measure with pre-tensioner since I swapped that over prior to measurement.
I just swapped to Recaro CS with SAB (not exactly BMWP): 18.6kg ex pre-tensioner.

I always assumed some numbers were off since I also have taken a few unsprung measurement weights and when I actually _shortcut_ calculate it, it does not add up to what's shown here and in another thread on m3post (all you need is car weights and linear spring rate). Measuring anything connecting the spindle to the inner pickup points is naturally harder to actually calculate.

[PRTSB1M]

Originally Posted by gmx

2020's era bump.

I have seen numbers for stock seats as:
54lbs (manual), +15lbs to electric.
34kg (pp1 of this thread) electric seats.

I measured 28.1kg ea for electric seats with memory, go figure. I did not measure with pre-tensioner since I swapped that over prior to measurement.
I just swapped to Recaro CS with SAB (not exactly BMWP): 18.6kg ex pre-tensioner.

I always assumed some numbers were off since I also have taken a few unsprung measurement weights and when I actually _shortcut_ calculate it, it does not add up to what's shown here and in another thread on m3post (all you need is car weights and linear spring rate). Measuring anything connecting the spindle to the inner pickup points is naturally harder to actually calculate.

So how much does your car weigh now with the Recaro CS?

[gmx]

Had it on scales before swapping the seats over at 1474kg no driver, 1/4 tank. Should be 1455kg now.

There's a few too many changes. Any aftermarket steel-bodied strut/damper is going to add more than the cast aluminum bodied. I forgot to measure the dampers/springs individually when I had the chance. The akra rear axle-back drops a whopping 200g, again I didn't measure it individually. Wagner FMIC (and anything else bar/plate) is heavy af, 5.8kg. Also the 6p Brembo caliper, bracket and Nissan GTR shape pads overall weighs slightly more than OEM caliper and pads.
Regardless here are my unsprung weights with the above in consideration:
54.20kg front corner, 54.05kg rear.

The only other differentiator are likely the wheels and the tyres:
These OEM wheel values are internet derived in this very thread supported by pictures. The Rays data from Rays themself. The tyres from tirerack (IIRC).
wheels:
Wheel Front 359 11.8
Wheel Rear 359 12.2
Wheel Front ZE40 8.16
Wheel Rear ZE40 8.42

AD08R at the time they were on scales in the figure above.
PSC2 245/35/19 10
PSC2 265/35/19 11.4
AD08R 265/35/18 12.7
AD08R 295/35/18 13.15

6kg overall drop from the wheel/tyre package.

I will have it on scales once I put some adjustable rear end-links on. Procrastinating for a while since it's a painful DIY.
Edit: I have 1.1mm thick PPF on the entire car. That stuff isn't light!

[changster]

Does anyone make carbon doors for the 1M?