weight reduction in a daily

[Draven]

So, after a few laps around Wakefield in Garth's 'rolla, which weighs about the same as the driver's seat in my supra, I've decided my voluptuous supra needs to go on a bit of a diet. The way the rolla didn't get pulled out as wide in the corners felt great.

The only problem is, it's also my daily... so this project is going to be full of compromises.

Plans so far (in no order):
* Remove passenger airbag (and before anyone mentions safety, if you've ever sat in the passenger seat of a JZA80, the dash is about 14 kms from the passenger), replace driver's steering wheel with sports steering wheel (again, ditching another airbag).
* replace driver's seat with bucket (saving 10+ kgs there)
* Odyssey battery (saving 2-3kgs)


I guess what I'm looking for is the generic areas where other people save weight, and what the effect is on comfort. Particularly things like removing the sound deadening in the footwells... I know it's HUGELY labour intensive, but how much weight do you save, and what does it do to cabin noise?

[laaag]

-If you have a spare tyre you could always remove and replace with a can of tyre weld.

-If you don't use the a/c or it hasn't had gas for yonks then i'd strip that.

-boot lining/carpet

-light weight rims (not sure what you've got)

-replace glass with lexen

just to name a few

[Draven]

- spare tyre comes out for track days
- boot carpets.... tempting for track days, not for daily (covers my surge tank, and other ugly stuff)
- rims are not as light as I'd like, looking into options (18" rims to fit big tyres and clear big brakes don't tend to be overly cheap)
- lexan is illegal... daily

[Gary]

speaking of illegal, might wanna check if you're allowed to remove airbags before doing it

a daily isnt the ideal candidate for weight shedding, specially being a supra which are quite heavy to begin with. not really that much you can do without getting extreme, and for the difference you'll make im not sure itd be worth it. for light cars, minor weight saving makes a noticeable difference, but for heavier cars you'd need to remove much more to get similar effects

could go lighter rims, but thats a different sort of weight shedding
do a80's have electric seats left and right? might be an idea to replace one or both with buckets, or just another factory spec seat (lightweight bucket seats generally not that comfy for a daily)
limit stereo, so no subs, no 45 speakers or copious wiring kits here and there, or amps. maybe just a nice headunit driving components or something
look into carbon fibre/fibreglass bonnets, though theyre illegal (not an issue normally if you paint it, but theyre illegal for a reason so careful)
remove the aircon system, but as a daily thats not really so cool (heh, geddit!)

getting a little extreme, but
carbon fibre front fenders, bumper. again quite illegal though as far as i hear
replacement door trims with something nice (CF looks great, money though)
looking to remove electric window motors, and reverting to a winder (a80's ever come with manual windows?)
ditch electric mirrors for something lighter (those hectik little drift ones maybe)
remove all carpet and deadening, and that dense mat stuff stuck to the chassis, but for a daily perhaps not so fun
remove jack and spare wheel, not so good for a daily though
various trim pieces, not so much weight by themselves but they add up... to a little bit heh

[Draven]

re: airbags... I know, but only driver's side was standard, and swapping steering wheels doesn't bother me too much.
Bonnet is already aluminium - not a lot of weight saving there (unless I get a genuine and non-reinforced fibreglass bonnet - factory is almost as light as most other options).
No options for non-electric windows
Mirrors... ganadors are an option, but don't save much weight (measured in grams rather than kgs)
Stereo is just 6 factory speakers (fronts, rears, tweeters) with a single din HU. No amp, no subs.

Unfortunately she's always going to be a bit fat. I know I'm not going to be making a huge difference... I'm looking to make a small difference to all aspects of the car

[Duk]

It's also worth removing weight from the extreme front to reduce understeer and rear to reduce non power oversteer, of a car.
I investigated moving the engine back in 1 of my cars 1.25 inchs and did the calculations for the engines polar moment of inertia on the car. Moving the engine back reduced the PMOI by about 5%.
However, if I moved the battery (about 15kg) from the very front left corner of this car to the boot, it had more than 3 time the effect of moving the engine (185kg) back 1.25 inchs.
Same said for the bumper bars which are very heavey in my example and because they are at the very front, reducing the mass or replacing with something lighter will achieve an excellent impruvement to weight removal ratio .

[RAd28]

Plonka - interesting to know how much of a difference it would make by moving the battery from the standard location (front left) to behind the passengers seat... i'd also be interested to know how much of a difference it makes having the car balanced (4 corner scales)...

[Toy77]

You could take out the 2j and fit a full house 3sgte.... like the GTC series (i think) in japan....

remover every 2nd bolt holding the car together.... seen that a couple times now....

Get creative with a hole saw......

Unfortunately you are paying the price of having a luxo barge - something set up as an awesome highspeed comfy tourer opposed to a track weapon....

[hosking1991]

why not just buy a cheap run-a-round car for a daily and then build the supra for the track

[RObErT_RaTh]

The only problem is, it's also my daily... so this project is going to be full of compromises.

Going on a diet but making compromises isn't quite as fulfulling in the end

[Draven]

well, supra also happens to be very sexy, reliable, and a lot of fun on the street.... if anything, I'd buy/build a different car to be my track weapon.

[limbo]

how bout carbon fibre bonnet, that should save you a few kgs, but they get pretty $$ for a supra

[Draven]

for what ends up to be a few kgs, money is better spent elsewhere.

Factory bonnet is 11kgs. A reinforced (legal) FPR/carbon bonnet is approximately the same.... the lightest bonnet on the market is 4kgs, the top secret FPR non-reinforced one (basically a sheet of fibreglass)

[CLG]

Easy solution is to stop comparing a Corolla with a Supra - completely different mode of commuter car, and you'll never get close to one another without sacrificing quality. If you do want to sacrifice quality, I can guarantee you, you won't want to take a woman out to dinner with it - so track pig quality shouldn't worry you!

[HAVABEER]

rip out speakers

maybe just leave the front ones in if you want to listen to radio