If big, nasty, American V8 power isn't what floats your boat, then the most exciting car to debut at next week's Detroit Auto Show will probably be the new 2015 Subaru WRX STI. With its arrival comes the latest iteration of Subaru's baddest street-legal rally machine. Here's what you need to know.

You'd be hard pressed to find many things wrong with the outgoing WRX STI. With a six-speed manual, 305 turbocharged horses, and one of the most potent all-wheel drive systems around, it's a first rate performance car.

But with the advent of a brand new 2015 WRX, Subaru must move onward and upward. And if the improvements made to the base WRX over its predecessor are any indicator, this could be the best STI yet.


What's it look like?

I'm gonna cop to a bit of hypocrisy here for a moment. Like my colleague Travis, I have not really been a fan of the way the new WRX looks. The new 'Rex doesn't look bad, per se, but it's uninspiring and unexciting.


But the new STI? I'm all about that shit, dude. I think it looks awesome and I haven't even seen it in person yet. Now you might be saying "But P. George! It's basically the same car, just with a giant wing, gold wheels and blue paint!"

Yes. Yes it is. And those things make all the difference. I think this may be my favorite STI yet.


Tell me more about that wing.

It's gorgeous. I want to marry it, but that's not legal where I live. Feel free to put it in historical context.


How about on the inside?


We don't know yet. Photos of the new STI's interior have not been "leaked" (read: maybe intentionally released to build hype) yet, but we can probably expect it to be a fancier version of the new WRX's interior — pictured above.

That's good news. The new WRX's insides are a big improvement over the outgoing car's plastic-y cabin. Since the STI commands a higher price tag, it's probably got a more premium feel with lots of alcantara like the old STI.

What's she got under the hood?


Ah. There's the big question. Based on a leaked spec sheet we got a few months ago, the WRX STI will be using a 2.5-liter four-cylinder instead of the WRX's new direct injection 2.0-liter turbo, itself derived from the motor in the BRZ and FR-S.

I see three possible outcomes. We'll either see a carryover 2.5-liter engine from the old STI, an entirely new 2.5-liter engine perhaps based on their new architectures, or a more powerful version of the 2.0-liter after all.


At any rate, it's reasonable to expect the new STI to put out more than the 305 horsepower in the outgoing car. I'm personally hoping for something in the 325 to 350 range, but that may just be wishful thinking.

What kind of transmission does it have?


Based on everything we've heard so far, a six-speed manual. Would you want it any other way? I've read that the WRX's optional CVT is actually pretty good, but the STI is for more serious people.

What happened to the hatch? I liked the hatch.

Me too, but at least for now, both WRX and STI are sedan-only. Subaru told Autoblog that the money that would have been spent on making a hatchback was spent on powertrain development instead, so don't expect the five-door to be making a comeback anytime soon.


Is it gonna go racing?

Heck yeah. Check this bad boy out. Expect to see it pull rallying duty later this year as well, because that's the entire point.


What does Subaru say about it?

Not much, besides the fact that they claim it will be the best-handling, best-performing WRX ever. From their website:

From the engine and suspension down to the leather stitching, the completely redesigned 2015 Subaru WRX STI will make your smile curl, your knuckles stiffen, and your gut feel like it's riding shotgun. Introducing performance and handling like never before. The all-new 2015 WRX STI. Inspired by racers. Made for us.



When does it debut for real?

Tuesday, Jan. 14. But at the rate things are going, we'll probably have more concrete details sooner than that.