Importance of weight loss?

[scott_lenhart]

Originally Posted by BlueDubbinTDI

um taking weight away from a car gives all the benefits from other parts all in 1. MPG, acceleration, and handling all improve with weight loss. That's why the most expensive performance cars are almost completely made of carbon fiber. A 500hp vehicle can make the same 0-60 times as a 1000hp vehicle all because of weight. That's where this car shines. It starts at around 2750lbs. Many cars cant dream of that weight these days. Wheels, exhaust, spare tire + tools and (heavy) battery delete can get you down another 100 easily. I cant think of a downside of losing too much weight in a car

Absolutely true-I agree.

[ZDan]

Thing is, it's a helluva lot easier to add 10% power than it is to subtract 10% weight. I'm a huge stickler on weight, but for a street car you can just about forget about taking out any amount that would be meaningful, that you could FEEL, while maintaining streetability. Most important thing is to start with a car that is already reasonably light.

I'm always annoyed with factory "special lightweight" models that remove useful things like A/C and stereo only to shave ~100 lb. off of the car that they designed to be too big/luxurious than it should have been in the first place. In particular, Boxster Spyder. "OOOH, no cupholder, it's a REAL serious lightweight race car!" While it weighs 95% of what a normal Boxster S with stereo, A/C, and a real convertible top weighs, and the same as the base Boxster with those features. BFD! Also, it remains a good 300-400 lb. more than a Miata, 800-900 lb. more than an Elise.

Also, the new Z/28. OOOH, it only has one speaker to SAVE WEIGHT! Meanwhile, it's still a 3800 lb. pig. It's like a very bad joke. Do people actually think it's neat to be able to point out their car doesn't have stereo sound in the name of saving about one tenth of 1% of their car's weight?! Idiots...

Anyway, light weight is very important, but it's just about impossible and can be very expensive to "add on" after the fact.
Designed-in from the get-go, lighter weight is CHEAPER. Don't make the car too big and heavy to begin with!

Kudos to Toyobaru for doing a great job on the twins.

[BlueDubbinTDI]

Originally Posted by ZDan

Thing is, it's a helluva lot easier to add 10% power than it is to subtract 10% weight. I'm a huge stickler on weight, but for a street car you can just about forget about taking out any amount that would be meaningful, that you could FEEL, while maintaining streetability. Most important thing is to start with a car that is already reasonably light.

I'm always annoyed with factory "special lightweight" models that remove useful things like A/C and stereo only to shave ~100 lb. off of the car that they designed to be too big/luxurious than it should have been in the first place. In particular, Boxster Spyder. "OOOH, no cupholder, it's a REAL serious lightweight race car!" While it weighs 95% of what a normal Boxster S with stereo, A/C, and a real convertible top weighs, and the same as the base Boxster with those features. BFD! Also, it remains a good 300-400 lb. more than a Miata, 800-900 lb. more than an Elise.

Also, the new Z/28. OOOH, it only has one speaker to SAVE WEIGHT! Meanwhile, it's still a 3800 lb. pig. It's like a very bad joke. Do people actually think it's neat to be able to point out their car doesn't have stereo sound in the name of saving about one tenth of 1% of their car's weight?! Idiots...

Anyway, light weight is very important, but it's just about impossible and can be very expensive to "add on" after the fact.
Designed-in from the get-go, lighter weight is CHEAPER. Don't make the car too big and heavy to begin with!

Kudos to Toyobaru for doing a great job on the twins.

I like the post. I like what VW is doing to their next GTI. Its losing 200 pounds due to massive R&D to get every ounce off and adding over 50tq with a new engine while also adding like 2mpg. I believe its going to be 210hp/250tq (VW numbers are at the wheels) and 3000 pounds from the factory. I REALLY cant wait for that car to release..then again..im a German fanboy more than JDM lol. This car kinda fell into my lap but it just feels so right. I wish the Europeans could make an affordable machine like the twins. The closest thing to it is the $80k Jag F-Type...

[ZDan]

Waitaminute, is the current GTI really 3200 lb.?! Sweet merciful crap...

We've come a long way from the original 1800 lb Rabbit

[BlueDubbinTDI]

Originally Posted by ZDan

Waitaminute, is the current GTI really 3200 lb.?! Sweet merciful crap...

We've come a long way from the original 1800 lb Rabbit

Yeah dude everything is getting heavier. More computer and safety shit ide imagine lol

[ZDan]

Looks more like 3050 lb. for a 2012 GTI: http://media.caranddriver.com/files/...swagen-gti.pdf

Still, anything over 2800 lb. for a "hot hatch" is, to me, obscenely overweight, even in this day and age.

[DarkSunrise]

The weight of the GTI changes a lot depending on configuration.
- A base 2-door with manual transmission is 3034 lbs.
- A 4-door DSG model with moonroof weighs in at 3213 lbs.

[Suberman]

Modern cars aren't built to drive, they're built to crash.

It is a self reinforcing parasitic problem. Occupant crash protection weighs a lot especially rollover and side impact reinforcements where crush space is very limited.

Once you add weight to give more crash protection you add kinetic energy to the crash event leading to the need for yet more crash protection. This cycle is extremely difficult to break.

Heavier bodies require more power and heavier suspension with larger wheels
and tires.

Remember the 1975 "Golf" was a three door, 4 spd with a 1.5 sohc carbureted engine, 13 inch wheels with 145/80 tires and a clever modified beam axle rear suspension which combined the axle with a roll bar. It couldn't get out if its own way but compared to similar competing products it was a revelation at the time. Made the last of the contemporary sports cars look silly.

[dotdotdotPaul]

I can't believe nobody's made the joke about "my doctor's always telling me to lose weight."

Although this might be a motivation for me to lose those 50 pounds she's always on about.

...Paul

[ZDan]

Originally Posted by Suberman

Modern cars aren't built to drive, they're built to crash.
It is a self reinforcing parasitic problem. Occupant crash protection weighs a lot especially rollover and side impact reinforcements where crush space is very limited.
Once you add weight to give more crash protection you add kinetic energy to the crash event leading to the need for yet more crash protection. This cycle is extremely difficult to break.
Heavier bodies require more power and heavier suspension with larger wheels
and tires.

Progress should be doing MORE with LESS (or, the same amount, anyway).

FR-S/BRZ are a perfect case in point. This car is precisely a brand new S13 240SX, at the same price point, with some added performance and much greater chassis rigidity, with essentially zero weight penalty vs. the 240SX from 25 years ago.

Meanwhile, the GTI has piled on about 800 lb. of additional mass.

Just because not many companies are making the effort doesn't mean it's impossible to have reasonably lightweight cars even in the face of modern safety regs.

If Toyobaru can give us a 2750 lb. FR-S/BRZ, I would suggest that a similar-weight or even lighter fwd GTI is totally doable. If the will was there...

[Stevo22]

A national level driver in my SCCA region joked about when he was racing a Miata the wheel weights went down to like 8 lbs a wheel, but he was still 50 lbs over weight. He said he was shaving weight every where but himself.

[Gary in NJ]

Originally Posted by ZDan

Progress should be doing MORE with LESS (or, the same amount, anyway).

FR-S/BRZ are a perfect case in point. This car is precisely a brand new S13 240SX, at the same price point, with some added performance and much greater chassis rigidity, with essentially zero weight penalty vs. the 240SX from 25 years ago.

Good point. A more extreme example is my 1972 240Z. The 240Z weighs in at 2400 lbs. This (two-seat) car was considered very light weight in its day. Fast forward 40 years and Subaru & Toyota have managed to add crush zones, airbags, electric everything and two useless seats in a car with very similar dimensions with only a 300 pound increase.

It really is an incredible feat and the product of obsessive engineering.

[diss7]

Quick weight loss for street 86.
Take everything out of the boot.
Take the back seats out, they're pointless anyway. The brackets and seatbelt receivers are just sitting there too, pull them out.
Pop the 3rd brake light out.
Leave the cover on the parcel tray. Looks like crap over wise and it weighs nothing. Leave rear side panels as well, no weight there. If you do take them out though, you'll also be able to get to rear belts. I didn't though, as that panel is joined to other panels around b pillar.
Rear mats as well, don't need them.
Under hood, boxer cover thing on manifold. Take bumper off, do you need the driving lights? Pull them out. Bumper beam, don't need that. Window washer bottle, just wash window when you put petrol in.
Do you need air con? Car is pretty cool with windows down and fan on. Pull that out too. The condenser, hoses, hear exchanger at the front. You'll need the JDM RC pulley to replace condenser though.

By now, you'll have a shit load of parts, and it's taken 2 hours and no money, well unless you took the ac out and had to buy the RC pulley.

Probably saved 50kg so far.

Take car for drive, it sounds and feels awesome. Let's do more of this. Have to spend money now.
Wilwood or AP racing brakes. They're lighter, but also unsprung, the best kind of weight saving. They might expensive, but just do it. Anyone saying pads and fluid on stock brakes will be good enough must drive like a pansy. It isn't.
Let's make car rev better, with lighter parts.
Toda pulley kit. Only kit I know that's under drive. Most kits are just lighter, this kit also drains motor less.
Toda flywheel and pulley clutch. Don't get a cheap/alloy flywheel.
Carbon driveshaft.
Tomei titanium cat back.
Take car for drive now.
Oh, get some wheels and tyres, but the stuff above will have bigger impact. Do stuff above first.
Wheels are hard, all stuff above is hidden. Wheels still need to look good. Everyone obsesses about wheel weight, but then put dumb 'meaty' tyres on, so end up with heavier wheel/tyre combo than stock. 205/40 semi slick on stock wheel will weigh less than forged wheel with big dumb tyre, and will have MORE grip. Put semi on forged wheel for win if you can.
205/40/17 semi (or any tyre that size also lowers overall gearing, which will make car feel even lighter.
More savings? Headers, seats. Bought all I can think of atm. That's the main ones anyway. At this point you'll just be chasing one or two pounds, and will be costly. Just wait till you need to replace something, then find the lightest functional option you can. Dont just but mods because mods are cool, you'll just undo all the coolness that you have done if you've done all the above.

Go race poorly setup poorly modded turbo cars around hills. Welcome to the new age, takumi.

[Anthony]

Originally Posted by diss7

Leave the cover on the parcel tray.

...What? Can you convert this to US-English?

Originally Posted by diss7

You'll need the JDM RC pulley to replace condenser though.

You have a link to this? I've tried looking before - unsuccessfully. I didn't know it was called an RC pulley though. I'm looking again right now, and so far no good results.