I was thinking about removing my backs seats... how much weight would I save? How much would it affect performance?

Also, what other things can I take out to reduce weight, and how much performance would I gain if the car lost 50 lbs? 100 lbs? 250 lbs? 500 lbs?

 

there are kits for removing your back seat... i forgot how much weight it saves. doubt youl be shaving off anything more than 100

 

I believe its about 35+ lbs for the backseats, Its helps slightly I think, but the main thing is all the room you get by taking them out. Its great, but you do get more noise in the cabin.

I have removed about 75 lbs out of my cooper with a the backseat, spare and a few little things, it it has made it more peppy, and it handles a little better. Since mines a Cooper Im trying to get every little bit of performance I can, the easiest way possible, and the weight reduction I have done has helped a little, and it hasnt done much to my comfort in the car. Im not really seeing much more than 75 lbs for a MC or 40lbs for a MCS that could be taken out without making the car unliveable as a daily driver.

 

one way to look at it is to divide the weight of the car by the bhp rating at the flywheel to obtain lb/bhp

my car runs approximately 13lb/bhp (200 bhp and 2,550)

so each weight reduction of 13 lbs will affect acceleration in the same manner as a power gain of 1 hp at the flywheel

of course stopping and turning are also improved by weight reduction - for example brake performance is normally measured in terms of units of swept brake area per ton, so here again lightness is an edge

i'm not aware of anyone running a street mini that can scale at less than 2,500 lbs - can anyone offer data on this point?

under SCCA STX rules for example the seats may not be removed, however the the battery may be replaced (20-30 lb saving depending on specifics)

i even removed the A/C, which was foolish for two reasons - (1) I regretted it when traveling from Boston to VIR one hot summer weekend, and (2) the STX ruleset was changed [takeback!] rendering that modification illegal in the class

weight reduction at the wheels has all the benefits listed above, and the addition plus of improving the physics of both acceleration and braking due to the fact that the rim/tire combination is rolling mass unlike the chassis

who has the lightest street Mini?

I wonder what Onasled's SCCA track mini weighs - stripped and with a roll cage and such... I'd still bet it winds up in the 2,300lb range...

Cheers,

Charlie

 

UKSUV on the R50/R53 boards has a pretty stripped out Cooper. The interior is completely stripped from what I recall, and he also has a carbon fiber hood and other lightweight parts. It is a street driven car as well!

We'll see if he chimes in.........

 

Im thinking my base cooper weighs about 2450 lb. Crub weight on the MC is 2524-36(Spare)-about 40(rear seat). I rarely have much more than a 1/4 tank of gas so that helps. But the you put me in the drivers seat, and all that work goes to hell. I need to do some weight reduction on the driver, that 300lbs kills the car's weight

 

FYI, here's what my 08 MCS weighs. Only the Jack is removed with about 1/2 tank of gas.

 

Bottoz, What options are on your car(sunroof / tire/wheel combo auto airCon, etc. I have a track spec car with no sunroof etc and would like to try an gestimate what my car might weigh in at.

 

bottoz,

those pictures are worth a thousand words - thanks for the post!

i would guess that the car was weighed without the driver, and without any corresponding allowance for driver weight - is that so?

my own (R53) sums - including 190lbs in the driver's seat, are as follows (the car has been lightened since)

LF (874) RF (806)
LR (547) RR (512)

LF Cross (1386) 49.4%
Front (1680)
Rear (1059)

take the driver out of total weight and you get (2547)


cheers,

charlie

 

Paul... I weighed my car at the scales at NHMS... 2421lbs.

Cooper with sunroof, no rear seats, no rear interior, race seats, rollbar, no A/C, lighter battery, light-ish 15" wheels, no driver/passenger, 1/2 tank of gas.

 

an R50 correct?

 

08 MCS 6 speed, Cold Weather, Premium and Comfort packages (so yeah, with the Sun Roofs and AC). 16 inch Bridge Spoke with stock Run Flat tires. Weight does not include driver. That's how I drove it on Miller... pretty much straight from the factory with just the jack removed.

 

Yes, R50 - 2003 Cooper.

Since the work on the car, I've had it at two different tracks.

One is really tight, and my best lap time dropped from 59.99 to 59.45

The other is a larger track (but still kinda slow). My best lap time there dropped from 1:31.5 to 1:29.3

Of course, along with the weight reduction, I also swapped the clutch and flywheel, and changed wheel size... so the time drop cannot be completely attributed to weight reduction.

 

thanks snid!

when I go from winter wheels (stock MCS 16") to the comp wheels (Kosei K1 15x7) the change is so dramatic that even my butt dyno can feel it...

in the order of 3% more thrust at the pavement I do believe!

and like weight reduction, that helps brakes too!

I hope the Solo crew schedule is coincident with one of your events at NHMS this year, as I should like to watch and if time permits pay my respects...

 

Another possible weight reduction up front would be to re-power the steering...

here's a Miata specific how-to, but the concepts would be similar, I believe:
http://www.flyinmiata.com/tech/depower.php

I find it odd that I haven't seen any MINI folks talking about depowered steering racks. I'm hesitant to try it, because the steering feel of my R50 Cooper is pretty damn good.

 

The R56's have electric power steering, not belt driven.

For my Porsche 944 Race Car, we remove the pump, belt, cooler and lines going to the reservior and loop the two remaining lines at the rack.

 

Yeah... so there's no parasitic power loss to remove from depowering the steering. But, there's still weight to be removed. And possibly increased steering feel.

Right?

I'm not an expert on these things...

 

You guys are forgetting a cheap hard/easy mod you can do to your ride too! Loose some weight your self. IM on the fat boy plan right now and im riding 8miles to work 2 x a week so thats like 32miles in 2 days. I need to loose a good 30lbs, tired of these dayum wedgies i get when i drop my screwdriver. I did an exhaust on my buddies car and he wanted me to go with him for a spin to try it out. I told him nope, it wont feel as fast with me in it.

 

I feel the same way. 50 lbs would do me wonders. I'm trying to watch my portions and food selection.

On another note anyone out there with a R56s with a CF hood? I wonder what the weight savings on that would be.

oops no popcorn for me gotta watch my girlish figure

 

I was thinking about that... :D

 

I'm going to start trying to add lightness ... anyone have any new ideas?

 

I removed the backseats but left the bottom portion. I noticed most of the weight is in the back-rests and keeping the bottom part reduces the cabin noise.

 

you could always try a crank pulley. Alta has one and claims that it's like reducing 75lbs from the car!!!! I'm giving it a try.

 

Is that pulley the same one as webmotorsports? Please let us know the results

 

an article I received from Mini Madness provided a very compelling argument against replacing the stock crank pulley with a lightweight non-dampening one like what Alta makes. I believe it only sheds a few pounds but it is rotational mass.

Good weight savers would be the back seats, sound dampening material and interior side/rear panels, battery, brake rotors and calipers, wheels, CF hood, toolkit/spare, flywheel/clutch, AC, stereo system, racing front seats. I bet that would get you well over 200 lbs. which would make a very noticeable difference with all performance parameters.

With that said, absolutely nothing comes remotely close to the gains from losing all the extra bodyweight!