if u guys are expecting light weight rims... i dont think so. the STI rims from the prototype weight in around 21.5 lbs, which isn't light exactly

If there was a good depowered rack, I'd love to, even just for the feel over the weight loss!

Mmm, misunderstanding.
Not planning to have a "sound system" - thinking more a single-din basic but good quality head unit and lightweight speakers (stock ones can be quite heavy, not just sound bad). Just looking for a spot in the dash to store things / put gauges, a little better audio quality, and lighter weight.

I don't need bass and there's an OK selection of lightweight speakers that don't draw really high. For the cubby-hole or plate to hold gauges, I have access and experience with glass and carbon, so that wouldn't be heavy either.

Right now I have a Bazooka (self-powered mini-sub) in my WRX that I got for free, but it's removed always for autox and often so i can fit a bike in the trunk, anyway.

Heres a question... How much would replacement titanium bolts actually cost?

I did see a documentry on the Bugati Veyron.
The bolts they used to bolt the 3 sections togeather cost $100 each. 16 needed just for to hold those sections togeather.
Im guessing it would had been the top of the line brand for aircraft use?
How much cheaper could you buy them for?

Have you purchased a car new car in the last 10 years? Most of them come with a couple 8 inch subs. I wasn't talking about ADDING anything.

What is so hard to understand here? It's like you've got some kind of mental block. I want to reduce weight where I can without sacrificing the daily drivability of the car. I mean, I've given detailed descriptions of exactly what kind of stuff I'm talking about....did you read them?

Yes. I am aware that if I strip out the interior, remove all accessories, acid dip the chassis, replace all the windows with polycarbonate, install carbon fiber body panels and attach 400 helium balloons to the roof that it will be lighter than what I'm proposing.

I don't care. I'm not building a dedicated track car. I am not a race car driver and there is no point in doing that.

I'm just looking for economical ways to drop about 1 person's worth of weight

I've driven it once...I went in the middle of the week, in the middle of the average person's workday, not on a holiday or weekend like most people.

It was deserted and I didn't see a single cop. I had a blast.

I think it's even more fun to just go exploring backroads though.

What cars are you looking at that come with more than 1 8 inch sub?

Most cars don't come with Subs unless you get the Premium sound system. To be honest I think you're overestimating how much weight you'll save with new speakers. Generally better sound = heavier magnets. Even then, Mids weigh less than a pound. So replacing all the speakers will net you a few ounces.

The problem is you're asking for the moon. Reducing weight usually isn't economical, if it is it's probably been done at the factory. That's why people who want to drop 100 lbs+ start ripping out interior.

I mean seriously go ask this same question on any car forum and most will just tell you to rip out the interior or spends tons of cash on lighter hood, trunk, doors, etc if they even make them.

I honestly don't think you'll be able to lose more than 20 pounds without either spending a lot of money or losing some functionality. It's a trade off. If it can be done on the cheap, usually they'll do it from the factory because it's cheap. They have a vested interest in keeping the weight down too.

Good luck and in a few years keep us posted how it goes. :popcorn:

This is how id loose weight without to much sacrifice in-cabin comfort

Interior :
- FIA approved recliner racing bucket seats, not because they are light weight, but because i really like the design and materials used over many factory seats has to offer. - $1600 (new) $700-$1000 (used) ~ 40-60lbs
- sparetire/jack/tireiron/ removed - $0 ~ 15-20lbs
- Removing factory sound system and running a simpler system with less wires. $400-$800 ~ 10-15lbs
- Factory steering wheel and front airbags removed, replaced by Nardi steering wheel and quick release by WORKSBELL ~ $150-250 ~ 15lbs

Suspension:
- Light weight wheels, and a low profile tire filled with nitrogen. $1700-$1900 ~ 40lbs
- Control arms resurfaced and drilled. $0 ~ 4lbs
- Cross Drilled / Slotted Rotors for weight savings over blanks than seaching for greater braking performance $250-$300 ~ 5lbs
- Larger+Lighter brake caliper (wilwood would be my first aftermarket search if factory brakes do not satisfy) $1200 ~ 15lbs
- Coilovers (may or may not be save weight) $1200-$1600 ~ 20lbs

Chassis:
- Front and Rear Bumper supports removed. $0 ~ 20lbs
- I would remove the factory sound deadning (most manufacturers use a hardened tar that range anywhere from 40lbs-120lbs depending on the car) and replaced with a liquid base sound deadener, that virtually weighs 1/3 of tar and mat deadners. $250 ~ 30lbs
- Removing Heat shields in the underbody. $0 ~
- Removing Metal in non-flexing joints and locations of the chassis. IE tailgate, wheel well, doors, roof. $0 ~ $20-80
- Carbonfiber hood - $600 ~ 15lbs
- Carbonfiber Trunk - $400 ~ 10lbs
- Drop aluminum gas tank to be replaced with, 8 Gallon Fuel Cell + Aeromotive fuel pump + hardware. $600 ~ 40lbs

Power and Drivetrain:
- Lightweight flywheel - $200 ~ 10lbs
- CNC Lightweight Pullies (crank,alternator,tensioners,AC)- $150-300 ~ 3lbs
- Aluminum driveshaft if a steel shaft from the factory is used. Carbon maybe, but not really interested.
- Full Titanium header back exhaust. $2400 ~ 60lbs
- Odyssey lightweight battery $180 ~ 15lbs

id expect a realistic drop of 250-300lbs with all this...but optimistically 500lbs. I'm really having a hard time gauging a weight loss on the FR-S especially when its target curb weight is competitive with the current Miata at 2400lbs. Id expect to spend anywhere from $4000-$8000 for good weight savings at that level.

+ added weight

+ SCCA approved 10pt roll cage
+ Front 4pt engine brace
+ rear strut tower bar
+ Larger 3way adjustable front and rear anti-roll bar
+ Chassis Brace
+ Transmission Brace
+ Aluminum Transmission Oil cooler
+ Aluminum Radiator
+ Aluminum Oil Cooler
+ AN fitted SS oil cooling lines
+ Stiffer Tranmission and Engine Mounts
+ Aluminum Subframe bushings
+ Stage 2 twin disk Clutch w HD pressure plate
+ Carbon rear diffuser
+ Aluminum Front under tray/splitter

~speculated major weight add ons
Widebody Aero (see sig pic)

I can lose way more than 20 pounds by re-doing the exhaust system and getting lighter rims. That's maybe 3000 total including the cost of tires, AND it has numerous other performance benefits with no downsides. I consider $3000 to be quite economical, especially if I Ebay the old rims/tires afterwards (though I'd probably keep them for winter tires)


Also: I've never said anything about replacing the speakers to lose weight. So....yeah.

I'm hoping that various members on this forum, once the car is released and we all start modding, can record the information and a sticky thread can be used to track all of the weights and weights for replacement parts....it'll help everybody make intelligent decisions about which mods to make for weight loss, as well as which exhaust/intake systems are good, etc.

Some excellent stuff! Yet again you've understood exactly what I was looking for.

There are a few things in there that I would avoid, for durability purposes. I think I'd keep the stock steering wheel as well, especially if it's available with a flat-bottom. I like the audio controls, and I've had my life saved by an airbag so I'm not too keen on removing that...

I think you could cut $1000 or so by going with a high quality CNC type material for the hood and trunklid, and it would only make a few pounds difference. Then again, if the hood is already aluminum, I wouldn't replace it.

Excellent point about the nitrogen filled tires. I had that done on my current GTI. I hit a horrible pothole outside of Chicago 1 week after buying the car, it bubbled the sidewall of my tire out more than 2 inches....but it didn't leak, didn't rupture....nothing! I was able to limp 50 miles into town and replace the tire. I'm convinced that had I been using regular air in the tire, I would have had a blowout at 75mph.

You would be wrong about the nitrogen helping your tire not blowout. It's called an impact break. When I worked at discount tire I saw it a lot. The kind of air in the tire will not affect the strength of the tire.

But so much of this is obvious. I'm honestly surprised you couldn't think any of this up yourself.

So, what's your budget for being economical? I'm curious now.

Nitrogen acts differently under compression....

I'm sure that tire would have at least been leaking after that.

Yeah most of this is obvious. It's still fun to talk about, get people's estimates, and maybe pick up a few small things I didn't know along the way.

In terms of economical....I don't think I'd want to spend more than about 6k on the car. Replacing the exhaust, rims/tires, intake, possibly headers, and the seats is do-able for that price so long as I do my own work. That'd net me some decent weight loss as well as a little extra power and sound. The wheels and exhaust would look pretty good too.

$6k just on weight savings or also including the engine mods you want to do?

Thanks iv added items and guestimations to that list, see my post again. I also wouldn't recommend removing safety equipment such as airbags or bumper supports, but its just something i do. I'm pretty harsh on the prices iv listed and optimistic about the savings. But it gives a pretty good ball park of what to expect. If you spend 6k on mods, I'm sure you can do lots of weight savings as a benefit to greater performance vs focusing on weight savings in general. The real weight savings happens with modifying the chassis, which severely complicates things and transforms the car to be impracticable.

If the car is not going to be tracked, this kind of money would probably be better spent on the engine, bang for buck, imo.

If you are tracking it and trying to keep it in a certain class, have at it.