03 WRX vs 06 WRX

[04wrx4keeps]

Everyone interested in this check out this months (well Nov issue but its out now) Sport Compact Car magazine, they have a testdrive of the whole 06 Impreza line giving a breakdown of changes and thoughts (they also drive the new Si for anyone interested). They say that the loss of the 500rpm's is no tradeoff at all and that the car easily pulls all the way to redline and feels much faster to drive than the previous models due to the added torque.

As far as I can tell the TR model is just where you would have started before adding any options to the WRX any other year. The biggest difference I have seen is that it's a single disc CD changer (if you upgrade to the Sedan trim level they add the 6 disc back along with a few other things) and automatic climate control. The TR starts at 23,995, the sedan at 24,995, and the Limited (which has leather seats, sunroof, etc...) starts at 27,495.

On the downside, they also say all the 06 models use a drive-by-wire system which sport-compact said was tolerable but noticable as well...

[Trainrex]

The pull up top hasn't changed, as far as I know. The previous 2.0L wasn't doing much beyond about 6,200RPM anyway. The new motor just gets you there much faster, but the upper range is just as good (if not better) than the outgoing 2.0L motor. I'm not sure about the new lower redline, but I imagine that reflashes will bump it up to 7,000RPM or beyond without consequence. A turboback and reflash on the '06 should make it easily match a Cobb Stage 2 pre-'06 WRX, if not beat it. The new motor is teh win.

A manufacturers redline is there for balance/valvetrain issues. A reflash may be able to bump it up 200rpm or so, but any higher is risking valve float, and/or the rotating assembly (bottom end) becoming unstable. I set my rev limiter at 7200, but I prefer not to bounce off of it. Valve float is a no-no.

[tarbaj]

Part of the reason for lowering the redline to 6500 is to keep it down from the STI. The STI has a 7000 redline. They have to keep the WRX at a certain level below the STI or risk people not paying the $$ for it.

[04wrx4keeps]

Part of the reason for lowering the redline to 6500 is to keep it down from the STI. The STI has a 7000 redline. They have to keep the WRX at a certain level below the STI or risk people not paying the $$ for it.

I dont know if I would buy that. 500rpm's isnt going to do too much toward making a WRX a buy instead of an STi, I mean the STi has the bigger turbo, bigger intercooler, better 6speed transmission and all around beefed up drivetrain, better suspension...etc, I think it's probably more of an engine protection thing, and to help decrease warrenty claims. For example the turbo may simply lose efficiency drastically over 6500rpm's (I havent looked at compressor maps and compared them to the 2.5L, so I cant say 100%) making a drop in HP and a risk of the compressor running much hotter and damaging parts (particularly the turbo itself). Remember the turbo is about the same size as the WRX's and now has 0.5L more pushing it.

[wrx wagone]

A manufacturers redline is there for balance/valvetrain issues. A reflash may be able to bump it up 200rpm or so, but any higher is risking valve float, and/or the rotating assembly (bottom end) becoming unstable. I set my rev limiter at 7200, but I prefer not to bounce off of it. Valve float is a no-no.

Listen to the man. He's on to something.

[tarbaj]

I dont know if I would buy that. 500rpm's isnt going to do too much toward making a WRX a buy instead of an STi, I mean the STi has the bigger turbo, bigger intercooler, better 6speed transmission and all around beefed up drivetrain, better suspension...etc, I think it's probably more of an engine protection thing, and to help decrease warrenty claims. For example the turbo may simply lose efficiency drastically over 6500rpm's (I havent looked at compressor maps and compared them to the 2.5L, so I cant say 100%) making a drop in HP and a risk of the compressor running much hotter and damaging parts (particularly the turbo itself). Remember the turbo is about the same size as the WRX's and now has 0.5L more pushing it.

I know what you are saying but if you plan to mod the car and get a turbo that will push the boost up high do you now want those 500rpm back? I would for a longer pull in each gear and more flexibility from the drivetrain. Doesn't the 06 WRX now have the same AVCS heads as the STI now also?

[04wrx4keeps]

I know what you are saying but if you plan to mod the car and get a turbo that will push the boost up high do you now want those 500rpm back? I would for a longer pull in each gear and more flexibility from the drivetrain. Doesn't the 06 WRX now have the same AVCS heads as the STI now also?

Well if your planning on modifying the car and messing with the engine management what do you care that they lowered it to 6500rpms for? Most good EM will let you make the rev limiter whatever you want...so just check that the valvetrain can take it (I'm pretty sure it can) and that the bottom end can too and do what you want... It still doesnt make any sense why wanting to sell the STi would make them lower the redline on the wrx...which is what I was responding to....

[John M]

On the Legacy the 6500 limit is just arbitrary to keep it from not being the same as the STi. It's damn near the same engine (only intake manifold is different) and they don't want to make that too obvious.

The plain 2.5 is plenty safe at 7k rpms, and it would be one of the few reasons I'd be willing to pay a "reflash ransom" (don't get me started about how Subaru tuning = ripoff).

[WRX-ERROR]

On the Legacy the 6500 limit is just arbitrary to keep it from not being the same as the STi. It's damn near the same engine (only intake manifold is different) and they don't want to make that too obvious.

The plain 2.5 is plenty safe at 7k rpms, and it would be one of the few reasons I'd be willing to pay a "reflash ransom" (don't get me started about how Subaru tuning = ripoff).

The redline was dropped to 6500 because the pistons in the WRX block aren't the same as the STi. The 06 WRX has a higher compression ratio over the STi. With that said people have already pushed the redline to 7k with no problems "so far".

Based on everything I have seen it seems Subaru has talked down the WRX to keep sales of the STi up. The WRX 5mt is beefed with thicker gears and duel cone syncros in 1st gear. Motor wise the WRX is nearly the same as the STi. The block, Crank, Heads and rods are all the same parts.

If you plan to mod your WRX (and who doesn't) you are better off getting the 06 WRX over the 06 STi. The 9k different just isn't worth it. Or just wait till 07 when the new STi comes out. Thats if the stories are true about the new heads.

[tarbaj]

Well if your planning on modifying the car and messing with the engine management what do you care that they lowered it to 6500rpms for? Most good EM will let you make the rev limiter whatever you want...so just check that the valvetrain can take it (I'm pretty sure it can) and that the bottom end can too and do what you want... It still doesnt make any sense why wanting to sell the STi would make them lower the redline on the wrx...which is what I was responding to....

Yes it most likely can take the 7000rpms. The point is that makes some people have second thoughts and think they can get more from the STI because it has a higher redline. You know there are guys out there saying if the WRX can go 500 over so can the STI rev that biatch to 7500rpm. There are also people who will be afraid to exceed the stock redline and think harder about going with the STI. Not everyone reads WRX boards and has the knowledge before they buy. Subaru is hoping for some consumer ignorance for that extra nudge to the STI. The STI is supposed to be their top model so nothing should be as good as it. It's all about perception. The typical new car buyer is not that informed.

On the Legacy the 6500 limit is just arbitrary to keep it from not being the same as the STi. It's damn near the same engine (only intake manifold is different) and they don't want to make that too obvious.

The plain 2.5 is plenty safe at 7k rpms, and it would be one of the few reasons I'd be willing to pay a "reflash ransom" (don't get me started about how Subaru tuning = ripoff).

Same thing here with the Legacy GT

[tarbaj]

The redline was dropped to 6500 because the pistons in the WRX block aren't the same as the STi. The 06 WRX has a higher compression ratio over the STi. With that said people have already pushed the redline to 7k with no problems "so far".

Based on everything I have seen it seems Subaru has talked down the WRX to keep sales of the STi up. The WRX 5mt is beefed with thicker gears and duel cone syncros in 1st gear. Motor wise the WRX is nearly the same as the STi. The block, Crank, Heads and rods are all the same parts.

If you plan to mod your WRX (and who doesn't) you are better off getting the 06 WRX over the 06 STi. The 9k different just isn't worth it. Or just wait till 07 when the new STi comes out. Thats if the stories are true about the new heads.

From what I can gather the WRX comp is 8.4 vs STI comp 8.2 not much of a difference.

Don't forget the STI still has the nice Brembo brakes standard, the 6-spd with DCCD, BBS Wheels and the better suspension. Those mods to a WRX add up to more than $9K. The STI is certainly worth it if you can afford the extra insurance and higher payments.

[Trainrex]

When you drive both, you realize that the STI is in a completely different league. I've never heard of a manufacturer lowering a redline so it doesn't compete with it's more expensive model. Odds are the tiny turbo runs out of breath above that anyway, so it wouldn't be making any more power above the redline. That blows the "competing with STI" theory away. Redlines are set for where an engine becomes unstable. How many of you here understand valve float? How many understand a bottom end being balanced? It may have the same crank and block as the STI, but that doesn't mean the assembly is balanced to 7000rpm.

[04wrx4keeps]

^^^^^Thank you....although all of this has been covered, some people obviously dont understand it at all....

[tarbaj]

You guys just don't understand the world of marketing and customer perception. Some people do but other obviously don't

[Devilbird]

Its a sound theory, with the same block in the 06 WRX as the STi Subaru does have to make sure there are obvious differences between the two. I don't think this means that the WRX can run to 7k as easily as the STi does. I certain intend to keep mine in the black.

But marketing has as much of an influence over technical specs as engineering does in some cases. The E46 M3 is a perfect example. The engine was designed for a 7500 RPM redline, but BMW marketing insisted that it had to have the same 8000 RPM limit as the 911. The result was blown engines in the first US spec E46s and a number of recalls and replacements. The M Roadster, which had the same engine and a 7500 RPM redline, expirienced no such problems.