Rally Cars

[warpdrive]

WRX is 2.0

Not anymore, NA WRX's are now 2.5T

[MameXP]

WRX is 2.0

There you go.

The new 2006 WRX has 2.5 BUT still NOT the same engine, different block, head, pistol... internal wise. But still more potential (force induction wise) than the older one due to bigger displacement

Note: Subaru is NOT NA modifed friendly so i'm prefering to FI

[MameXP]

Its still different engine.

If you still say they're the same with performance upgrade its like saying ITR and civic has the same engine LOL. For gods sake, dont say that or you make a fool of yourself

[waitin4BOOST]

Definitely a different engine when gonig Force Induction.
There are many things you have to account for when your pushing more compressed air in large volumes...i think about 1 bar in this case (14.7psi) and @ the same time have your car reliable for daily driven.

Some things to make your engine reliable when going FI usually involves..
-bullet-proofing the block (so it doesn't grenade under load)
-low-compression pistons (Al. alloy in this case)
-beefier connecting rods
-head bolts (definite must)
-larger fuel injectors (more air - more fuel)
-I think STi's are Power water cooled...instead of an Air intercooler
-there is alot more other little things ie. engine management, more agressive ingnition system, map sensors, etc.

It's really not just the engine...when you tally up all the parts that is involved in building a reliable FI vehicle it really takes a toll on your budget. Going a bit farther I believe most of the money was spent on RnD and tuning. If you look @ the dyno chart for a STi the power curve is constant, there are rarely any dips and spikes. That said, as the old saying goes...you pay for what you get, and in this case 300hp/300tq

And...i didn't even touch on suspension....bottom line, when your going any type of force induction be it turbo/supercharger the engine will require strengthening and proper tuning to be reliable as a daily driven car.

side by side comparison WRX vs STi
http://www.cars101.com/subaru/imprez...tml#mechanical

[Ride-On]

Good to know the differences - thanks.

I should point out that by no means am I suggesting that a modified 2.5i or 2.5RS = WRX -- I was merely suggesting that you get more bang for your buck. This is also more biased to WRX vs. 2.5RS than a comparison to the STi...

For the bulk of WRX/STi drivers... I'm willing to bet they aren't pushing their STi beyond 2.5i/2.5RS abilities... so might as well save $10,000+

[mudmojo]

For the bulk of WRX/STi drivers... I'm willing to bet they aren't pushing their STi beyond 2.5i/2.5RS abilities... so might as well save $10,000+

I would say you'd lose big time on that one.

Unlike most 4 bangers, the STi 2.5 produces lots of torque and a wide powerband with gearing to make every corner exit a pleasing experience and is thus easier to coax speed out of without knowing the ins and out of keeping, say, an older 911 Turbo on the road or even certain NA's like the S2000.

In the stopping, department the Brembos make things much more effortless. Good competition in the 06 WRX brakes though but the STi gets a big nod when compared to a 2.5i. Not so much in a one stop trial but in repeated abuse cases, the Brembos shine in comparison.

Traction? The 2.5i is a lowly 2WD AWD car while the STi is I think the only production NADM car which is actually 4WD all the time. The EVO might be there too but not sure of the JDM/NADM differences.


The STi, with factory settings, is about real world speeds and can make any joe blow average driver look pretty competent if they don't hit corners hot.

Stock rubber? 2.5i rides on crappy (and I do mean crappy) all-seasons while the STi rides on very performance oriented summers.


This is of course all in spirited driving. If what you're saying is that STi drivers don't drive fast on the street because they'll quickly get in trouble by being that public menace then yeah ok, you can keep your shirt... but not in the winter.

[waitin4BOOST]

Haha I kind of agree with Ride-on's point of view...after all, sadly...the painful truth is, our speed limits are 60/100kph respectively.

I would still love to own one and would not shy one bit in taking it on an auto-x run.

[warpdrive]

Traction? The 2.5i is a lowly 2WD AWD car while the STi is I think the only production NADM car which is actually 4WD all the time. The EVO might be there too but not sure of the JDM/NADM differences.

Huh???? what the heck are you talking about? Manual transmission Subarus (all of them), and Audi Quattro sedans use a true 4WD full time system. Full Time 4WD is not unique to Sti's

[MameXP]

Huh???? what the heck are you talking about? Manual transmission Subarus (all of them), and Audi Quattro sedans use a true 4WD full time system. Full Time 4WD is not unique to Sti's

I think he means somethine else? I have heard that they're not same.

Onething unique about STi is the power ditribution to wheels. Its AUTOMATICALLY adjusted thro corners. While the WRX always remain 50/50 front and back.