Weight savings cost/benefit benchmarks

[lucid]

Originally Posted by J08M3

Ha, good point. Why not just sticky it here in the General forum?

Since this is really discussion about potential modification to reduce weight, the general forum is probably not the best place. Among the technical forums, the "Suspension Brake Chassis" forum is the best target for this sticky.

If people have other weight savings ideas, I will integrate them into the original post.

[OC ///M]

Originally Posted by lucid

Good to hear from you OC!

This is a long shot, but if you just happen to have that 380mm brembo kit sitting around collecting dust--the way expensive BBKs do--can you weigh the parts again?

Right!

Ha! no sweat.

Actually, since you mentioned it, I have had the OEM fronts back on the car for a while now. I just so happened to have dropped the car off today to get the BBK re-installed and have specifically asked for the Brembo's and the OEM's be weighed prior to install. We should get an "independent" report of the weight from the performance shop who's re-installing them, hopefully by tomorrow...

[lucid]

Originally Posted by OC kid

Ha! no sweat.

Actually, since you mentioned it, I have had the OEM fronts back on the car for a while now. I just so happened to have dropped the car off today to get the BBK re-installed and have specifically asked for the Brembo's and the OEM's be weighed prior to install. We should get an "independent" report of the weight from the performance shop who's re-installing them, hopefully by tomorrow...

Thanks man! That's cool...

[stylinexpat]

Originally Posted by Epacy

Odyseey.

Attachment 147189



Good thread Lucid. I will stay tuned.

I am familiar with the effects of over-moding and the impact on the ride. I hope to steer clear of that with this car.

Looks like we lose a lot of cranking AMP power. I am looking for a lightweight battery but want a good one.

[michaeldorian]

Wow. Just went through the entire thread. One of the best on this site. Let's keep the weights of aftermarket parts coming. Hopefully this turns into THE resource for e9X weight info. Subscribed.

[SV Concepts]

EXCELLENT thread. Saved for future reference

[lucid]

Added info on Mini/E46CSL battery.

[graider]

if you are fat, loose about 100lbs. that is huge weight saving right there.

and take off your bling gold chain. that's like 10+hp for you.

[bavarian06]

Without stripping the heck out of your car, the removal of the washer fluid is a smart idea, 8lbs is a lot. The best bang for the buck would be the battery and exhaust swap and a cf trunk.

[Radiation Joe]

Don't know if this was mentioned earlier, but I just weighed the Performance Friction stock replacement rotors at 18.2 pounds. That's a 4.5 pound savings over OEM.

Compare that with the 5 pounds I'll save per corner with the RAC RG63s and that means 29 lbs of unsprung weight removed from my car.

[swamp2]

Originally Posted by Radiation Joe

Don't know if this was mentioned earlier, but I just weighed the Performance Friction stock replacement rotors at 18.2 pounds. That's a 4.5 pound savings over OEM.

Compare that with the 5 pounds I'll save per corner with the RAC RG63s and that means 29 lbs of unsprung weight removed from my car.

Sounds good. Pics? Floating or non floating? Diameter and thickness vs. stock?

[Radiation Joe]

Originally Posted by swamp2

Sounds good. Pics? Floating or non floating? Diameter and thickness vs. stock?

Bimmerworld for the win.

[klammer]

saw somewhere on here that stock roof with moon is 55lb. would like clarification, if available, and how much weight is saved by going the cf route, as well its effect on cog by changing the weight at the top of the car...

[marwol]

Does anybody have weights for the Tecnocraft Carbon Intake System or the Macht Schnell Stage II?

------------------------------------------
The german company Faktor offers a Lithium battery which combinates leightweight with good performance.

Here is a link to the 40AH version:
http://www.faktor.de/index.php?optio...mid=41&lang=de

shortfacts:
weight: 6kg (approx 13,2lbs)
capacity: 40AH
cost: 290€ (approx 390$)

[PhoenixM3]

Something not discussed, but essentially free is the removal of sound deadening material which is typically bonded to various spots of the chassis in areas where sound penetrates the passenger compartment. I still have an E46 M3 and pulled approximately 30lbs of this stuff from trunk and rear seating area. I'm certain that there's more, but the car is still a DD.

We're 5 weeks away from picking up my wife's E90 M3, and I'm hoping that this will be a relatively easy mod to shed some weight.

I have some tips for easy removal of this stuff if anyone is interested. The only costs involved would include a heat lamp, a few PLASTIC paint scrapers, and a can of carb/choke cleaner. Oh, time to remove the trunk liner and rear seats and carpet can't be discounted either.

PhoenixM3

[wwjd15]

Wow! The ratio of Amuse door panels makes me believe it's a steal!

[Nautik]

Would love to see information about declining certain options such as:

• Navi
• Power Seats
• Power Folding mirrors
• Heated Seats
• DCT
• EDC (vs what some aftermarket suspensions weight maybe?)
• Premium Sound
• Moon Roof

Hopefully someone knows some of this information...

[klammer]

would actually like to see some weights of vehicles and what mods were done. Have a few more ideas to entertain and then plan on weighing her. Think he'll be in good fighting shape

[HBspeed]

Originally Posted by Carlos@MORR

I have personally started a lightweight project for my future Individual M3 and the cost of replacing parts for lighter ones is absurd. Between lighter trunk, door panels, seats, and exhaust you are at almost $15,000.

Even though the notion of a lightweight M3 is very appealing, for the cost of reducing weight on the E90/E92 Chassis, it`ll be cheaper and more effective to purchase a light set of wheels, brakes, suspension and add a supercharger kit effective increasing your power/weight rating which is the end goal after all.

You are correct, but I believe the whole spirit of weight loss is to retain the naturally aspirated nature of the engine while increasing performance.

If/When I get an E92 M3 I will do exactly as you suggest other than the supercharger. However the way I look at sports car buying is: if you aren't going to be satisfied after spending the 10-15k or so on high end Wheels/tires, suspension and brakes... you might as well just put that money towards a car that in stock form will be superior anyways. For most here that generally means a Porsche, namely a GT3.

The problem is aftermarket weight loss solutions are never going to be cost effective. That is why we should all be begging for BMW to distribute the costs more by making weight loss come straight off the assembly line.

Sadly the high revving M engine days are gasping their last breath so we are going to be forever limited to what is available today as far as BMW goes, barring the miracle of a E92 CSL version showing up here in the US...

[lukester]

Great thread. But the issue with removing weight from the M3 is that it changes the car.
If you go through it like I did - basically the stuff which makes sense - only removes weight from the rear of the car which changes the handling.

I did:
Full Akrapovic Exhaust (~23kg/50lbs)
rear seat delete & remove all unnecessary parts and insulation from the trunk (~28kg/61lbs)
55Ah Battery (~11kg/ 24lbs)
Recaro Pole Position seats driver and passenger (~29kg/ 64lbs)
OZ Ultraleggera Wheels with Michelin Pilot Cup tires (~7kg/ 15lbs)

All mods make sense for me as I love track days and would have done it even if it doesn't make the car lighter (e.g. the seats, wheels, tires, ...)

My M3 should be +/- 216 lbs (98kg) lighter than stock at the moment.

But....the car switched from a slightly oversteering M3 to an more understeering M3. There's no power steering available any more as it just
pushes over the front wheels.
(you can still drift it but you have to force it)

It's logical. A lot of the stuff has been removed from the rear or the center of the car.
Nothing from the front or under the hood. So the weight balance moved away from were it should be.

Will weight my car within the next weeks and I'm really interested to see the final results.

What can be done against this new handling?
I'm gonna try some 265/35-19 Michelin Pilot Cup on the front, too. At the moment the setup is 235 and 265 which is not perfect if you like an oversteering M3.

But I'm missing ideas what to do with the front.

A carbon hood will only help with ~4kg/ 8.8lbs. Not really worth it.

What I saw ... but I'm not sure if it's a good idea. Replace the big underfloor plate (it's directly under the engine) with a more lightweight part as this thing is really massive (and we do have good streets in germany so there's no need for such a engine protection).

[shay2nak]

Originally Posted by T Bone

Voltphreaks http://voltphreaks.com/

this battery is great. I've had it in my Exige for 3 years (along w/other lotus peeps). No probs. I had the 1st gen and had it upgraded to the new spec. For only 5lbs, lasts about 12 days car just sitting in the garage. Saved me 23lbs in exige, for you guys I'm sure it would be at least double that.

Also, IND just put up their new carbon hood. Might want to add that also.

[RPM8300]

Originally Posted by lukester

Great thread. But the issue with removing weight from the M3 is that it changes the car.
If you go through it like I did - basically the stuff which makes sense - only removes weight from the rear of the car which changes the handling.

I did:
Full Akrapovic Exhaust (~23kg/50lbs)
rear seat delete & remove all unnecessary parts and insulation from the trunk (~28kg/61lbs)
55Ah Battery (~11kg/ 24lbs)
Recaro Pole Position seats driver and passenger (~29kg/ 64lbs)
OZ Ultraleggera Wheels with Michelin Pilot Cup tires (~7kg/ 15lbs)

All mods make sense for me as I love track days and would have done it even if it doesn't make the car lighter (e.g. the seats, wheels, tires, ...)

My M3 should be +/- 216 lbs (98kg) lighter than stock at the moment.

But....the car switched from a slightly oversteering M3 to an more understeering M3. There's no power steering available any more as it just
pushes over the front wheels.
(you can still drift it but you have to force it)

It's logical. A lot of the stuff has been removed from the rear or the center of the car.
Nothing from the front or under the hood. So the weight balance moved away from were it should be.

Will weight my car within the next weeks and I'm really interested to see the final results.

What can be done against this new handling?
I'm gonna try some 265/35-19 Michelin Pilot Cup on the front, too. At the moment the setup is 235 and 265 which is not perfect if you like an oversteering M3.

But I'm missing ideas what to do with the front.

A carbon hood will only help with ~4kg/ 8.8lbs. Not really worth it.

What I saw ... but I'm not sure if it's a good idea. Replace the big underfloor plate (it's directly under the engine) with a more lightweight part as this thing is really massive (and we do have good streets in germany so there's no need for such a engine protection).

Luke, I have an E92 M3 and I run 265x35 Dunlop Star Specs all around on 18x9s - it works very well and helps with understeer. You have to be careful what you ask for because when you are at the limit on a track and the rear gives, it will not be as forgiving as a staggered setup. This is fine for me and I like it very much - your throttle control and counter steering just has to be a little bit more quick to respond to what the car is doing. I do much more autorcross than track events so weight loss is big for me, and steering with the throttle is big as well.

One idea that I had which the experts that read this can comment on, is stripping out everything you want and then possibly adding a little weight to the rear to balance the f/r weight distribution. My rough estimates are the same as what has been stated in plenty of times - after I take out the back seat, strip the trunk, and switch out the front seats I would not be suprised if track ready weight of the car (1/2 tank) was right around or even below 3500. I have already thrown the lightest 18x9 rims I could find at a descent price and I run Dunlops which are about the same weight as PS2s. The issue I see is that at that point the f/r distro will be more like 53/47. I had an E82 135i for a couple years before this and as everyone knows, it understeers like crazy. That was mostly due to suspension geometry but the f/r weight distro didnt help, which was also about 53/47.

That brings me to the idea - I heard the 135 has extra weight in the rear to help the f/r distro - I know it will have a marginal effect but I wonder how the M3 would feel if you stripped it down but then added just enough to the very rear of the car to keep about 50.7/49.3 f/r. Experts give us your opinions.
Tom