2006 Subaru WRX vs WRX STI

[TuffGuy]

I'm assuming that the WRX runs less boost, has a smaller turbo, and has different suspension settings.

Do they have the same internals (ie, would the WRX be able to handle just as much boost as the STI), and are the differentials the same?

TIA

:beer:

 

[Bullhonkie]

Good comparison here: http://www.cars101.com/subaru/impreza/wrxsti2006.html

Bottom end is the same AFAIK, not sure about the heads. WRX has smaller turbo, smaller IC, smaller injectors, no front LSD, viscous center diff (IIRC) instead of DCCD, 5-spd MT or 4-spd AT, can be had with leather, different wheels/tires, no Brembos, no HIDs, cosmetic stuff, etc.

 

[TuffGuy]

Great link, thank you! :beer:

The internals seem to be different. The WRX has a compression ratio or 8.4:1m while the STI has a ratio of 8.2:1. Which I don't quite understand since the bore and stroke are the same.

But it answered my question of whether or not the STi is worth $8k more. Yes, it is.

 

[Tom]

Originally posted by: TuffGuy
Great link, thank you! :beer:

The internals seem to be different. The WRX has a compression ratio or 8.4:1m while the STI has a ratio of 8.2:1. Which I don't quite understand since the bore and stroke are the same.

But it answered my question of whether or not the STi is worth $8k more. Yes, it is.

Compression ratio is determined by combustion chamber size and valve timing, not just bore and stroke. Such a small variation could just be a thicker head gasket, but it's probably head design since larger valves would really help the increased turbo boost.

 

[Sheepathon]

You also get a fat wing.

 

[Reckoner]

I never really understood the need of an STi unless you take it to the track. If you don't plan on doing this, you might want to go with the WRX

 

[RagingBITCH]

Originally posted by: PaulNEPats
I never really understood the need of an STi unless you take it to the track. If you don't plan on doing this, you might want to go with the WRX

Then what's the need of any sports/go fast car then? Speed is meant to be on the track, period.

 

[Reckoner]

Originally posted by: RagingBITCH

Originally posted by: PaulNEPats
I never really understood the need of an STi unless you take it to the track. If you don't plan on doing this, you might want to go with the WRX

Then what's the need of any sports/go fast car then? Speed is meant to be on the track, period.

There isn't a point unless you live in an area where there's little to no traffic or the autobahn.

 

[Shaotai]

regular WRX is 2.0l isn't it? STi is 2.5l...

*EDIT* Oh CRAP, they all have 2.5l now! Sweet!

 

[NutBucket]

Originally posted by: PaulNEPats
I never really understood the need of an STi unless you take it to the track. If you don't plan on doing this, you might want to go with the WRX

Then you must also believe there's no need to modify cars

Oddly enough, Bullhonkie forgot to mention the suspension is pretty different between the two.

 

[tbike06]

Also the brakes are a lot better too. :heart:

 

[ai42]

There are a ton of differances. FYI the new WRX has the EJ255 block and the STI uses the EJ257 block. Not a whole lot is known about the EJ255 block as I don't think many have really pushed that engine much. But the EJ257 block is semi-closed deck and can take boost like mad. Also the STI has far superior seats than the WRX.

 

[MikeMike]

http://img.photobucket.com/albums/v618/eurozex/sti.jpg

 

[NutBucket]

Originally posted by: ai42
There are a ton of differances. FYI the new WRX has the EJ255 block and the STI uses the EJ257 block. Not a whole lot is known about the EJ255 block as I don't think many have really pushed that engine much. But the EJ257 block is semi-closed deck and can take boost like mad. Also the STI has far superior seats than the WRX.

How far do you want to go? Forester and Legacy guys are getting plenty out out of the 255.

 

[Pocatello]

The WRX is plenty fast for most of us, plus its smaller wing doesn't attract too much attention from the lawmen. One draw back with these beauties is your fuel mileage will be in the low 20s MPG , instead of high 20s or 30 MPG like most midsize sedans out there.

 

[NutBucket]

Small price to pay.

 

[DivideBYZero]

Spring rates, suspension, strutbrace, bigger turbo/more boost, seats, DCCD, LSD's, STi specific engine internals which even goes so far as the valves themselves being different to the WRX variant.

And a red intake, known as a 'red top'.

Side note. Until the '06 model the UK STi was still a 2.0 and produced the ~300HP, just as the 2.5 does now...

JDM and UK get all sorts of other variants like the WR1, Spec C, s202/3/4, etc. The scooby is a very interesting car, IMHO.

 

[NutBucket]

Back in my Honda days you'd refer to a B18C5 (ITR motor) and H22A from a Euro Accord-R as "red top"

 

[Reckoner]

Originally posted by: NutBucket

Originally posted by: PaulNEPats
I never really understood the need of an STi unless you take it to the track. If you don't plan on doing this, you might want to go with the WRX

Then you must also believe there's no need to modify cars

Oddly enough, Bullhonkie forgot to mention the suspension is pretty different between the two.

My WRX is stock