A weighty matter

[Petrus]

I know, I know, a lot has been written about the Spyder and weight. Also, nothing will be definitive because you don´t know what you don´t know and there is always more.
Lastly I am relatively new to the Spyder and still on a steep learning curve about the car so very much aware that there is a lót more to know and understand about it.
Nevertheless, because for me one of the main purposes of life is sharing the learned, I will try ... share the learned.  Oh, appologies for the lighthearted bits.

To share more info and provide perspective witt different pov I have given a link to Spyderchat thread.
I do not agree with all of it and suggest to read it with caution. Same my own ponderings ofcourse. Use your own head  too.  So; feel free to, no; PLEASE CONTRIBUTE!

Ok, first the link to the thread on spyderchat worth reading befóre going on and ponder about....
https://www.spyderchat.com/threads/a-stripped-out-spyder-weighs-x-xxx-lbs-see-inside.51309/
Right.
...or wrong 🙂

As usual it all depends. Is it a track car? - in which case the above is imo only a half way station leaving a lot of meat on the bone, or
is the car still to be used on the road? - in which case some of the above is not applicable.
I use my car on the road, so that is the perspective for the rest of this proza.
Because I live in the mountains my use is mainly on B-roads. Relatively very well maintained ones but still mountain B(ack) roads, so undulating with weird cambers/crowns and the occasional ruts/potholes caused by overloaded agricultural vehicles. As such  need the OEM ground clearance and softish spring rate/ damping.
For the rest creature comfort is relative. I mean; carpet and embellishing plastics are just optional feel-good.
Whether one considers explosive gas bags in a small cabin safe or not is open to discussion and my pov is that they are not and thus unwanted ballast.

Ok, the Soyder weight watching according to Petrus:
The most important guide line is: What´s not there anymore weighs nothing, is a complication less and removing stuff comes free of charge.
- So I started taking out the frunk and all associated stuff and replaced the wheel repair goodies with a foam can behind the passenger seat. Also removed the power steering.
- At the back mounted an 800 grams LithiumFe battery, motorcycle muffler (later on a decat pipe), removed charcoal canister, drip tray, sound insulation, the air duct in the rear wing.
- The interior I liberated from the ´air´-bags, luggage compartment doors, floor matts and carpet. Next swapped the reclining seats for lighter buckets. Yes plural because unlike the spyderchatter I lóve charming company to ask for a ride! I´d be happy to put the more comfie OEM seat back for the occasion!!
Ah and unobstructed the view by removing the interior mirror.
Still have the sound system in and thus door cards. That may very well become victim of weight watching too in the near future.
- Very important; the wheels. Mounted the lightweight Enkei RPF1 rims with minimalistic but high tensile steel nuts.
- Various bits like ash tray/cup holder, sun visors, antenna et all, are simple to remove and all adds up to a couple of kilos.

Last time I weighed the car it had shed 110 kilos. That should be 135 now.  That is including adding aero bits, a front strut brace, Carolyn´s head support and Snelbaard´s alloy under brace.

As was observed, any weight taken off this light, sensitive car is noticable and the more you take off the more more noticable it is. No, not a typing error: The process is like a snowball rolling off a steep slope; it is progressive.
11 kilo off a 1100 kg. car is 1%.
Only 9 kg. off a 900 kilo car is also 1%.
The lighter the car gets; the larger the relative effect of weight reduction, thus the more noticable it is. That is very motivating, not to say addictive.
Well, ánd I tend to see this elegant, sensitive car in the femine so taking things off great fun.
Yes, I will admit it; I am an addict 🙂

[JB21]

I'd guess my track car is between 950-1000kg without driver and 1/8 of a tank of fuel?

2004 FL 2ZZ/C60 with MR2 diff
Stripped OE hardtop (soft top fully removed)
Rear stripoed
Front carpets stripped (full dash and door cards in situ)
All airbags removed
1 x fibreglass bucket and 4 point harness
6 point cage
Fully braced
Whiteline front and rear ARB's
Coilovers
Race battery
Lightweight OZ 15" wheels
Custom header and cat
Cobra quad tip back box
OMP 300mm wheel

I'll be weighing it at Oulton next time out.

[Petrus]

Thank you JB.
Looking forward to the result.

[m1tch]

I have a full list of parts I have removed from my car (some have been put back), have also mentioned which parts are bang for the buck like the ECU shield, rear bin lids etc.

There are other parts that don't really make a difference such as the carpet which doesn't really weigh anything compared to the sheer size of it. Will post up the full list at some point, every 10kg is worth around 0.1 seconds at the quarter mile.

[Petrus]

Will post up the full list at some point,

Please do! Much appreciated.

every 10kg is worth around 0.1 seconds at the quarter mile.

Ditto effect every time you brake, change direction, go up an incline or through a corner.
Now times 10 for the 100 kilo ;-)
It really is a weighty matter.

[Petrus]

There are other parts that don't really make a difference such as the carpet which doesn't really weigh anything compared to the sheer size of it.

Still several kilos (what was it 3,5?) and véry easy to remove. Getting the air duct from the inner wheel well was more of a hassle for less than a pound. Still took it out.

Missed the ECU shield ...  Not aware of a worthwile thing there. Can you illuminate please?

[m1tch]

There are other parts that don't really make a difference such as the carpet which doesn't really weigh anything compared to the sheer size of it.

Still several kilos (what was it 3,5?) and véry easy to remove. Getting the air duct from the inner wheel well was more of a hassle for less than a pound. Still took it out.

Missed the ECU shield ...  Not aware of a worthwile thing there. Can you illuminate please?

Here are the weights I have measured so far, the ECU shield is a metal plate that goes over the front of the ECU, held in with 2 TS5 bolts if I recall, it weighs 459g or just over a pound.

Weights are in kg:

ECU shield  - 0.459
Box for Toyota locking wheel nuts - 0.082
Smaller exhaust manifold heat shield  - 0.588
Larger exhaust manifold heat shield  - 1.202
Engine vanity cover  - 0.357
Toolkit  - 3.039
Spare wheel  - 11.2
Frunk plastic cover  - 1.4
Frunk lid  - 1.218
Frunk well  - 3.418
Frunk under bracket (long) (1 of 2)  - 0.138
Inside trim piece where seatbelt threads though (left and right)  - 0.714
Front floor mats  - 1.927
Trim over rear bar  - 0.764
Wind deflector  - 0.62
Parcel shelf  - 1.585
Rear carpet  - 1.652
Rear bin - passenger - 0.902
Rear bin - driver - 0.901
Rear bin door - passenger - 1.22
Rear bin door - driver - 1.205
Sides of rear bin trims  - 0.344
Rear bin fitting hardware  - 0.056
Hardtop blanking plates and fitting hardware  - 0.119
Radio  - 2.086
Aerial relay  - 0.094
Ash tray/cup holder/12v socket  - 0.484
Speakers/tweeters  - 2.452
Passenger side sun visor  - 0.268
Brake duct (aftermarket intake pipe instead of elbow)  - 0.18
Heatshield on passenger side  - 0.121
Stock intake pipe (MAF to TB  - 1.412
Stock air box  - 0.917
Assorted bolts/covers etc from items already removed  - 0.247
Broken seat adjuster (side wheel)  - 0.032
OBDII reader plug  - 0.032
Locking wheel nut  - 0.107
Glovebox  - 0.997
Passenger seat  - 13.9
TTE spoiler  - 2.525
Frunk under bracket 2  - 0.12
Aerial and wiring  - 0.913
Evap canister  - 0.776
Evap canister bracket  - 0.228
Door trims (that go along the sills) x 1 - 0.482
Trim to the side of the pedals x 1 - 0.206
Assorted nuts and bolts from removal of soft top  - 0.191
Lock down bracket in the centre of the crossbar  - 0.235
Metal strip that wraps around the back of the car clamping softtop into place  - 0.432
OEM alarm siren  - 0.555
Heat shield on rear subframe that encases OEM airbox  - 0.761
Additional aerial wiring  - 0.033

Still have these to weigh/update my spreadsheet:

Intrument surround
HVAC surround
Carpet
Sound deadening under carpet
Door cards without handles
Under steering wheel trim
OEM exhaust heat shield behind bumper
Alarm sensitivity adjuster

[james_ly]

Interesting list, shows that it's pretty difficult to get significant weight out of an MR2. I've taken out the frunk bits, jack, and rear bins, steering wheel. Any more than that and I'd have to spend money or make it worse on the road...

[Petrus]

Thank you for the detailed list Mitch; and for the ECU lid!! ;-)

Looking forward to your weigh bridge result. Will try to weigh mine again coming week. Was 920 last time.

p.s. took the cubby floor out and had a good look at it but the lid stays in.  Not confident enough about removing the mechanical and em protection for half a kilo.

Fingers crossed Rogue responds; that would be 7,5 kilos incl. sound system.

Interesting list, shows that it's pretty difficult to get significant weight out of an MR2.

When the battery needs be replaced, you can loose 10+ kilos. Then there are muffler, cat, precats to find another 20+.

And there is more to be found; 100 kilos is not extreme. Meaning that some 10% of the car´s weight can be chucked relatively easy and that is a lót; significant.
I hópe to get close to 150 kilos. (still no response from Rogue about the door panels...)

I've taken out the frunk bits, jack, and rear bins, steering wheel. Any more than that and I'd have to spend money or make it worse on the road...

Well, if you empty the front, Í would say that you need to take out the same from the back to restore how it went and a bit móre to get a bit less understeer.
To improve the appearant straight line instability on the highway, you need to tackle the aerodynamics which is three tenners max.

And spending money to make it wórse...
Spend some on lighter wheels and it will instantly go bétter!

Btw, I hope you repláced the steering wheel ;-)

[M.R.]

100 kilos is not extreme.

True. I have done ~100kg diet and I wouldn't consider that as a extreme. True number is bit more, since I haven't weighted every little bit. Car still has full interior. Except few minor things behind the seats. Car weighted 888kg without driver and loose stuff and with half tank gas. From this point any notable weight reduction is hard to achieve and it is expensive. At least for street car, it is bit easier on race cars.

I would like to get weight to 850kg or less, but I also would like to have some sort of rollbar and slightly less noisy muffler.

[Petrus]

100 kilos is not extreme.

True. I have done ~100kg diet and I wouldn't consider that as a extreme. True number is bit more, since I haven't weighted every little bit. Car still has full interior. Except few minor things behind the seats. Car weighted 888kg without driver and loose stuff and with half tank gas. From this point any notable weight reduction is hard to achieve and it is expensive. At least for street car, it is bit easier on race cars.

I would like to get weight to 850kg or less, but I also would like to have some sort of rollbar and slightly less noisy muffler.

Imo, anything under 900 kilos, even for a PFL, is already borderline hard core for a street car.

Indeed, once that much lightened, it gets into track-only territory. Even then, 850 is sériously light. As you observe, every kilo more (or less) gets exponentially more difficult/extreme. You´ll need to gut the soft-top, gut the doors, go plexi for the windows, lighte bonnet/rear lid etcetera.

Chopping the windscreen, adding a half cage, no passenger seat, gutted dash, lighweight brake calipers, stuff like that, would see you wéll under 850 with an imo übercool proper spyder...

For a stréét car though; 900 kilos is quite a difference already. I was on 920 measured, then mounted lighter seats, took the carpet out, deducted the inlet, chucked the mirror, went decat pipe, so should have been well under 900 at that point.

My intenton to put it on the weigh bridge again has been thwarted for the moment though; need the OEM muffler /cat in till I have sorted the blown bike muffler.

Also still no word from Rogue about the door panels. Probably won´t bother...

[Petrus]

With the modded exhaust off and the OEM bits ready to refit did a q&d; 23 kilos difference incl. the decat manifold.
WOOOFFF 
Fingers crossed an aluminium resleeve will be more resilliant and repack with microfill less LOUD.

Still on the fence about the door panels. I am not using the radio/cd so that adds to the panels meaning it ís a weighty matter.
The loss in comfort I rate on par with the gain in cool.
A bit of a downer that Nick seems awol. I am very much interested in first hand experience with the things.