Subtracting less weight up top via light weight material roof, actually lowers the central mass of the car. (Also effecting CoG to be lower as well). The roof is actually a very ideal part of the car that could be better in weight savings.

As far as the roof panel actually seeing torsional stress or experiencing any sort of energy is kinda sketchy. Some cars have roof panels that do experience plenty of stress. Some cars panels roof panels actually do provide chassis rigity. As far as the BRZ/FRS...i cant remember what the frame looks like off the top of my head. I could probably take a pretty good guess.

I'm with Orbitalellipses on this one....a BRZ STI is unlikey at this point.. BRZ tS or a self-built BRZ tS is more probable.

^Ditto

They'll come w STI option parts, but no BRZ STI

Okay cool thanks. By roof material I was talking about how would it affect torsional rigidity. In the Ken Gushi Greddy FRS build, they had a picture that showed some of the roof, it looks like reinforcements between the B pillars, and a single sheet of metal bent to the roof's shape sitting on top of it. I highly doubt the 2 creases that are there for aero do anything for the chassis.

If they come out with a lightweight roof that would be cool.

http://www.caranddriver.com/reviews/...t-drive-review

http://media.caranddriver.com/images...-s-520x318.jpg

STI, tS, "special edition"... I don't care what it's called. Just don't want to pay for stock wheels/suspension and inevitably spend $3000+ to replace them with aftermarket wheels/tires/suspension+aero and leave me w/ unsellable stock parts that other owners won't need/want for a while. I'm hoping for a "tuned" package even if it's not for another year. I have a feeling buying these parts as dealer accessories will = wallet rape.

Yea agreed, if it's some nice handy improvements that are easier for the manufacturer to do than for me to do, it would be nice if they could have some upgraded parts installed as a package at a non-rape price (uh 700 dollar diffuser, 500 dollar spoiler, what?) from the factory. Lightweight roof, possibly quarterpanels, some aero bits, brakes in an "STI package" for a reasonable price would be cool. No need to replace the hood/trunk if they're already aluminum. As far as exhaust goes, I think it might even be best if they leave that stock since different people have different goals when it comes to that.

In the case of a thin sheet metal roof panel, it's not going to be all that rigid on it's own. That said, when you fasten it to points on the skeleton underneath, it helps to prevent those beams from moving in relation to each other because the panel will not want to stretch. Use a stiffer material like CF, and it becomes even more rigid.

Same thing if you glued together toothpicks to make a skeleton of a cylinder. It wouldn't be all that resistant to twisting on it's own. Take a piece of paper, stretch it around and glue it to the frame. The whole structure becomes more rigid, even though paper isn't that rigid on it's own.

What's up with all those stickers? Didn't realize there was a market for that

+1 great use of example.

Reminds me of the Nismo brochure for the R32 and R33 with stickers/decals that run along the body.

Lets rename the tuning shop STI...to BOB.....

A Impreza WRX STI limited would be the highest trim out of subaru for that particular model. tS (tuned by BOB) would designate that the tuning shop BOB had a go at it to offer a package for the consumer market.

So essentially Impreza WRX STI Limited BOB would be the highest trim with BOB sports package. or WRX STI tS

Confused yet? thats because subaru uses STI as a marketing badge..while their sports division is STI as well. Subaru has 2 STI names that represent 2 different things.

lets get more confusing!
"Limited Trim Production Models" are different from "Limited Production Special Models".

Subaru Limited Trim Production model, is a Production model that has (usually) all the available goodies and option you could want in a high spec subaru of that particular model.

Subaru Limited Production Special model, is a small production of high spec cars that BOB has taken, given free reign on (an important element), and packaged as a Special Model.

Subaru Limited Trim Production models tS, is a production model that has all the goodies and options available, plus BOB has personally added their touch too.

Impreza
Impreza WRX
Impreza WRX STI
Impreza WRX STI Limited
Impreza WRX STI tS
Impreza WRX STI S206

Under all these models...BOB has only touched 2 of them. Among those two models. BOB has only given free reign on 1 model..the S206.


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in 2014 its likey to look like this...because this year IMPREZA is splitting from WRX. Many articles are saying that the tuning shop STI will no longer touch the Impreza..this is false. Subaru STI will no longer touch Impreza. True. Again it seems awkward ..but (STI) and (Tuned by STI) are different.

Impreza Sport
Impreza G4
Impreza G4 Limited
Impreza G4 tS

WRX
WRX STI
WRX STI LIMITED
WRX STI tS (STI, tuned by STI...seems redundant, but now that you know they are two separate things it makes more sense)

I'm loving the black mirrors and black wheels on the stripped down version. I really was hoping that'd be purchasable here in the states

Yeah but without this engine we would not have this car...

While a dry-carbon hood by STI would be awesome, it would be more expensive than most people would pay. Way more expensive than your average ricer will pay, too. The hood is already aluminum, which is light (check out pre-08 WRX/STI hoods)...the low-dollar FRP hoods that most people buy actually weigh more. I see these as rather convincing arguments against a carbon hood of any type, until money has been better spent elsewhere (see: brakes, suspension, power). Weight reduction is expensive; proper weight reduction (pre-preg dry carbon) is even more expensive.

To really simplify it to MY understanding of it, tS is a parts-bin catalog. In JDM-land Subaru offers several models in tS form. They just have all the STI catalog options.