So for my first post on NASIOC I post in the wrong forum and am made to feel like an idiot for my question. The thread is locked and I was directed to this forum so I'm reposting here. BTW since I'm knew to the forum I'll introduce myself. I have a 1979 Porsche 930 and a 1987 BMW 325IS which have both seen time on a road course style racetrack on DE days. My girlfriend has a 2002 Subaru WRX which has over 40k miles on it, most of which were with me behind the wheel and I've also taken the wrx to the track (my birthday present from her). Although I got off to a rough start I'm happy to have joined the NASIOC forums. Below is my original post and Handsdown's response followed my response to handsdown. Thanks.
I wrote:
"The 2.5 NA motors remind me somewhat of the BMW 325 motors since they have similar output, gas mileage, and displacement. However, both the motors are aging and BMWs will get a new 2.5 with 218 hp and even better gas mileage for 06 models. My sister will be needing a car in a couple years when she gets her license and an outback would be nice for both her and the family to have as a ski trip car. So I was wondering if there were any rumors about new 2.5 NA motors for the car I plan on purchasing in a few years. Thanks "

Handsdown wrote:
"the "news and rumors" forum has a lot of information about possible engine changes in the coming years, but nothing is general or factual knowledge yet. you can try to search around in there, but for now the best news is that the new 2005 2.5 motors are MAF air sensor and have a redeigned intake manifold... i doubt we'll be getting both significantly more power and better milage, but only time will tell.


why do you think subaru and bmw are similar? bmw engines are inline, where as subarus use horizontally opposed engines... they're very very different and i don't believe they compete in any way shape or form, they're completely different classes of automobiles...

if i were you i'd decide on other factors, like the need for AWD or comfort or ride quality... the engine shouldn't be your primary concern if you're looking at the lower trim models of the impreza... what makes subarus great is their AWD capability and handling... and that special something that draws us enthusiasts to the car.

once again, you might want to look at the News and Rumors forum... they'll probably be able to help you out... but just because BMW is coming out with a new engine, doesn't mean subaru will even start thinking about it... they're far more interested in competing with honda, mitsubishi, and american car companies... BMW just isn't comperable, it's in another class.

try the news and rumors here: http://forums.nasioc.com/forums/forumdisplay.php?f=63"


I respond:
Well first of all, ofcourse the bmw inline six and subaru flat four are very different. However I think that they have similar applications in sedans. The 2.5 motor is the base motor for the legacy which has been aimed at swaying BMW buyers who want to save a buck so while not the largest competitor, bmw is definitely in subaru's mind when it comes to the legacy. I could have referred to the Acura TSX instead with its 2.4 liter 200 hp motor. This must be a competitor to the legacy since it was recently featured in head to head comparisons with the legacy in both road and track and car and driver. In those comparisons they used the turbo legacy, but many people like the fuel economy of the TSX so subaru has to counter with a decent economical yet marginally sporty motor (honda, acura, bmw, everyone is working on motors that meet those requirements). The reason for the specific BMW reference is the fact that their motor is aging and inferior in hp and mpg when compared to motors like that found in the TSX. BMW finally came around to remedying this for 06 so while I don't think this means Subaru MUST do exactly the same thing, I do think they feel the same pressure( not from BMW, but from the other manufactures that either already have more modern motors or are planning them). Is this THAT crazy a conclusion?

Welcome aboard! :) Sorry for the rough start you got. Unfortunately you run into that here occassionly. Look at it this way, it can only get better, right? :D

Bob

yeah um... hi.

try to research the forums before you post

we have a lot of people just randomly post in the wrong forum
and it can be upsetting.

that aside.... welcome.

and I killed that "other thread" no need to feel like an 'idiot' okay?
we were all new here once :)

and now we are in the right forum!
let the info flow begin :)

Yargk, your points are very well taken and I can understand your desire for better fuel economy. Now although I'm by no means denying that the 2.5L couldn't use a bit of updating, the AWD does reduce it's mileage somewhat. I owned a fwd Subaru in the early 90's and can assure you that it got VERY good mileage. I know this doesn't help you with your question but when comparing AWD vehicles exclusively, Subaru does quite well in the mileage arena.

Regardless, I wish Subaru would spend a little more effort improving the economy of thier entry level vehicles as well.

... BMWs [engine] will get a new 2.5 with 218 hp and even better gas mileage for 06 models. ...How did you become certain that information is true? Did BMW announce this? I don't think so and I doubt such an engine will be available in the US next year, but maybe you are not living in the US and specifications are different overseas.

So I was wondering if there were any rumors about new 2.5 NA motors for the car I plan on purchasing in a few years. Thanks "

I think the 06 legacy NA 2.5 will have a little more HP and better emissions (similar to the california emission car now).. There will also be variable valve lift to some degree on the 06 engine as well. My guess for HP would be near 180.

']How did you become certain that information is true? Did BMW announce this? I don't think so and I doubt such an engine will be available in the US next year, but maybe you are not living in the US and specifications are different overseas.

European Car February among other sources. It's pretty much confirmed. 2006 e90 325i gets 218 hp and the 330i gets 255 hp. I am in the US, maybe it will take a bit longer to get here, but with 300 hp G35s I think the new motors aren't that far off.

Subie Gal, no worries for killing the other thread. The idiot part was about Handsdown's reply that seemed to dismiss my premise. On many forums, posts are simply put in the right area instead of locking, is this ever done here? (just wondering). Also, discussion of a new NA powerplant seems to fit in both the technical NA forum and the rumors forum to me especially since the technical forum has the subtitle "Technical discussion about any NORMALLY ASPIRATED Subaru powertrains." Any meant also future to me. I'm sure a website as well organized as this one has a page that clearly states that ANY talk of the future goes in the rumors section, would you please direct me to it.

Yeah, usually threads in the wrong forum are just moved not locked ... oh well just part of the NASIOC experience. Its a really good forum overall.

Anyway, the biggest change I know about is adding AVCS (active valve control system). So far its only on the turbo and H6 motors but I can see it coming to the 2.5na eventually. There's an article in the winter 05 Drive magazine, which you can find at www.drivesubaru.com

The point about AWD is apt; Subies are never going to get as good mileage as similar FWD or RWD cars.

we have a lot of people just randomly post in the wrong forum
and it can be upsetting.


People who get "upset" by a post being in the wrong forum either need to be on meds or have the meds they are on adjusted.

I think the 06 legacy NA 2.5 will have a little more HP and better emissions (similar to the california emission car now).. There will also be variable valve lift to some degree on the 06 engine as well. My guess for HP would be near 180.
That's what my district manager is hinting towards as well except power bump should be across the board, not just legacies.

I wonder if they will return to a DOHC setup?

Bob

Interesting discussion. I'm curious how BMW gets 200+ hp out of the same N/A displacement as the Subaru engines, is it simply a product of 2 extra cylinders or something else? For emissions stuff, I've found the best resource is here:

http://www.epa.gov/greenvehicles/smcar-05.htm

Interestingly, one of the BMW 2.5 models actually outscores or matches most of the cleanest engines from Honda, which says a lot. The turboed Subaru engines (2.0 & 2.5) seem to be pretty dismal on emissions, while the N/A ones are ok, somewhere in the avg. I don't know if this has something to do w/ boxer engine design or Subarus in general. It does beg the question though- if people are pushing a 3.0 turbo for a future lineup, can Subaru even come up with one that's Tier 2 compliant?

BMW is coming out with these nice I6 with magnesium block or maybe only crank.
It is supposed to make parts lighter so red line could go up along with HP ratings.
BMW engines already have double VANOS (AVCS, VTECH equivalent).
I wonder when they are going back to direct injection (I think they made direct injection aircraft engine in 40s - BMW 801 - it powered Focke-Wulf FW190 fighter).

Krzys

I remember running crude calculations once and myself and a couple of others figured that if the 2.5NA engine was DOHC and had AVCS, 200-210hp is quite possible. If AVCS is already being added, why not add another cam. Variable lift would certainly make it a lot easier to achieve those numbers without sacrificing fuel economy or low end power. It would certainly be nice to get that engine in the Legacy to compete against the TSX and even Audi's new 2.0T base engine. Similar benefits are obvious for the Impreza line as well even with the increased cost/sticker price.

TS - 168hp SOHC 2.5
RS - 210hp DOHC AVCS 2.5 (TS + 42hp)
WRX - 260hp DOHC AVCS 2.5T (RS + 50hp)
STi - 320hp DOHC AVCS 2.5T (WRX + 60hp)

Magnesium block would be a little pricey don't you think? Probably just crank.

Direct injection should be a big future trend; seems to be able to boost both mileage and power.

I agree with the direct injection. I think subaru should go to it. I think with Variable valve timing and variable lift along with direct injection, gas engines have a lot more room for improvement before we give up on them and go to Gas/electric hybrids or fuel cell technology.

I think the 06 legacy NA 2.5 will have a little more HP and better emissions (similar to the california emission car now).. There will also be variable valve lift to some degree on the 06 engine as well. My guess for HP would be near 180.
balbino, so you expect AVCS heads on all 2005 2.5L engines for the 2006 model year?

I think the 06 legacy NA 2.5 will have a little more HP and better emissions (similar to the california emission car now).. There will also be variable valve lift to some degree on the 06 engine as well. My guess for HP would be near 180.

H'mm "variable valve lift" N/A engine? Not with AVCS too unless the EJ25 returns to DOHC. Does this mean an SOHC with variable lift? A DOHC 2.5 with AVCS AND Variable Lift could easily crank 200HP. This is interesting :)

I believe the new BMWs will have a magnesium (or ally thereof) block. Don't know if a 2.5'll get 218 hp on our gas and emissions, though. I'd have to walk home and dig through my old Autoweeks.

The new 3 series manuals get a hill holder, too, like Subarus used to have.

Subaru's trying to move up in the world, with the Legacy being an alternative to the A4 (and thus aslo the BMW). So I can see a *little* comparison, but not much yet. Subaru could do it; look where BMW was 30 years ago (I owned a 72 Bavaria a few years ago).

The new 3 series manuals get a hill holder, too, like Subarus used to have.

Are you sure? Do you have a link?

BTW, the US-spec Forester still has the Hill-Holder clutch.

Bob

The NA 2.5 engine in the 06 legacy/outback. Will be a SOHC with a variable lift on one of the intake valves. The other 3 valves will operate at a constant lift. This engine will not have variable valve timing. At least that was what I was told.

Magnesium block would be a little pricey don't you think? Probably just crank.



Aircooled VW's had magnesium blocks. Apparantly they arent that expensive to build, since they were about the cheapest things you could buy.

People who get "upset" by a post being in the wrong forum either need to be on meds or have the meds they are on adjusted.

I don't mean this directly at anyone and I don't want to offend, but I tend to agree with this statement. To me, it's like the people who get upset by capitol letters. I don't post IN ALL CAPS, but come on, how can that upset you? Next thing, roman numerals will be highly offensive.

...roman numerals will be highly offensive.

Aren't they ?

Interesting discussion. I'm curious how BMW gets 200+ hp out of the same N/A displacement as the Subaru engines, is it simply a product of 2 extra cylinders or something else?



Well, as far as more power from the same displacement, Subaru could do it too. It's just a matter of revs, breathing, variable value timing, and sophisticated computer control. If you look at the 3 liter in the new Subaru B9 Tribeca, it makes 250 hp. That's 83.3 hp per liter. If the 2.5 had the same efficiency, it would make 208.3 hp.

Are you sure? Do you have a link?

It's what I saw in Autoweek a month or so ago. Thier site isn't so good for searching, and I don't know if they put that much detailed info on it. Then again, though I have a subscription I don't have an account or anything with them.

Magnesium block would be a little pricey don't you think? Probably just crank.

Actually the new 6 cylinder BMW is manesioum-aluminum composite: crankcase and cylinders are in aluminum, whereas the outer part of the block is in magnesium.

They offend me III out of V times.
-Allen

I'm confused. I thought the new BMW "2.5" motor is actually a "3.0" motor detuned. But BMW decided to call it "325" instead of having two 330 (one regular, one lite)?

Maybe someone can confirm?

Actually the new 6 cylinder BMW is manesioum-aluminum composite: crankcase and cylinders are in aluminum, whereas the outer part of the block is in magnesium.

Didn't know that ... what's the advantage of the magnesium?

I'm confused. I thought the new BMW "2.5" motor is actually a "3.0" motor detuned. But BMW decided to call it "325" instead of having two 330 (one regular, one lite)?

Maybe someone can confirm?

not true

I read that in 2006 Volvo will offer a 2.5l or so engine that will crank out about 210hp if I recall, wich is way doable with variable valve lift... And as far as I know, by trying to move upscale on the market, Subaru IS aiming at BMW. Look at the B9 Tribeca, it's clearly in direct competition (or at least trying to be) with the likes of the X5. If Subaru wants to lure in new customers, they need to work on both their engines (crank the output of the N/A engines) and their interior trim.
We're still not up-to-par even with mass-produced vehicles such as the Civics and Corollas (on the fit and finish of the interior)

The new BMW 6 cylinder engine family uses magnesium in the outer part of the block to reduce overall weight, as well as weight on the front end to get better fuel consumption due to less weight, as well as close to 50/50 weight distribution - magnesium has less specific weight than aluminum. It is my understanding that the outer magnesium part and the inner aluminum part are cast together simultaneously.

There are supposed to be three versions of this new engine for the time being (all referenced as 3 versions, they will also appear in the 5 series):

323i - 2497 cc; 177 hp @ 5800 rpm; 230 Nm @ 3500 rpm
325i - 2497 cc; 218 hp @ 6500 rpm; 250 Nm @ 2750 rpm
330i - 2996 cc; 258 hp @ 6600 rpm; 300 Nm @ 2500 rpm

Note that the 323 and 325 have the same block but very different torque. The different torque values with the same engine capacity are probably due to one engine having Double-VANOS and the other one not, or possibly due to a variable intake system. All engines will have a new valvetronic version.

A 320i will have a 150 hp 4 cylinder with 150 hp and later there will be a 318i with 129 hp. A 335d a diesel with sequential turbocharging is also planned, producing 272 hp.

New BMW blocks are magnesium/aluminum castings. Mag gets the weight down; aluminum in used in areas like the bores. The only issue with magnesium is that you have to be careful machining it - otherwise the "swarf" thrown off can ignite, with spectacular results.

Subaru 4 cylinder power units do not get high specific power outputs in NA form. Honda has shown that a "clean" 100bhp/liter or more is quite possible (S2000), and around 80+ bhp/liter is very doable in a modern sedan-tuned engine (Acura TSX and others). This would say that Subaru should be able to get around 200 from the 2.5, given modern valve controls and electronics. Btw, the H6 3 liter hits the mark - 250 hp from 3 liters is just over the 80 bhp/liter mark.

Subaru achieves 100 bhp/liter in the 2.5 LGT, but with a fair bit of boost to make it happen. Granted, this gives the engine a lot of torque - probably more important than horsepower in general from the driver's perspective.

As to fuel economy, IMO there are two issues - the "drag" of AWD, and the lack of proper gearing, in that there is no "highway cruise" gear. Our LGT is much less economic on long runs than my (now old) C5 - about 10 mpg off in fact.

Hi

Wow I've been here almost a year now. I found NASIOC by accident looking for Info on the Forester XT and then when I knew I was buying a Subaru stayed.

Finally I found a place to talk about all the Subaru's I've been reading about for the past 6 years.

Welcome to one of the biggest Car forums on the net.

The Legacy 2005 2.5L NA is a slightly improved version of the Subaru 2.5L NA engine found in the Impreza's. It isn't revolutionary as it only brings a 3BHP increase and Subjectively doesn't seem much different than my 04 2.5L NA.

Yes the Rumours about the 180BHP new version abound, but we will just have to wait and see what happens there. Subaru usually will just add a turbo when more power is called for although how much power this creates and the resultant performance doesn't always match to the numbers.

the 2.5 XT Forester on paper has 210BHP 235 LB-FT but makes performance numbers that exceed all other Subaru's with the exception of the 2.5 T STi 300BHP 300 LB-FT.

The Legacy GT has a middle of level 2.5 T 250BHP 250 LB-FT engine but is still marginally slower than the Forester.

What may happen though with a slightly redesigned impreza is the incorperation of the H6 3.0L engine. 250BHP 219LB-FT. in its NA version. What numbers would a Turbo version produce? That's anyones guess and most members dream. The only thing that really holds this back is the mileage requirements that Subaru has to meet without turning all of it's cars into paper trucks.

I wonder if they will return to a DOHC setup?

Bob

Why should they? From my understanding they dropped the DOHC setup because they found they can make the same amount of power with the SHOC.

Plus it's less Parts & I don't have to have bloody kuckles just to change the plugs.

Well, it's true that they make the same amount of power with the SOHC, but that's because the SOHC is still working 4 valves per cylinder. With the low rev limits required for the large bore 2.5L engines, the rockers in the valvetrain are the least of the engine's high rev worries.

Now, when we're talking about AVCS, you can get a better tune when intake and exhaust can be adjusted separately.. so DOHC comes back into play.

So, as for making high HP Naturally Aspirated versions of the 2.5L engine, Subaru will need to raise the production costs as the internals will need to be fabricated out of stronger lighter materials in order to acheive the higher redlines needed for high rpm operation. Then add on the cost of dual AVCS.. which needs enough components to work on 4 camshafts, and you've got considerable additional expenses for a car that's generally marketted to people looking for something a step above your average economy car.

We have the WRX.. I wouldn't expect any sporty N/A motors to reach our shores.

I'm confused. I thought the new BMW "2.5" motor is actually a "3.0" motor detuned. But BMW decided to call it "325" instead of having two 330 (one regular, one lite)?

Maybe someone can confirm?

Well,

According to Edmunds, you're right. They have a review of the new 330 up on their website and it states: "Of keen interest to Bimmer fans is the fact that both the 325i and 330i are now powered by 3.0-liter engines. The only real difference between the two is output."

Interesting.

Well,

According to Edmunds, you're right. They have a review of the new 330 up on their website and it states: "Of keen interest to Bimmer fans is the fact that both the 325i and 330i are now powered by 3.0-liter engines. The only real difference between the two is output."

Interesting.

Do they both run on premium gas?

Bob

Well,

According to Edmunds, you're right. They have a review of the new 330 up on their website and it states: "Of keen interest to Bimmer fans is the fact that both the 325i and 330i are now powered by 3.0-liter engines. The only real difference between the two is output."

Interesting.

When he first asked the question I thought he meant new=2005.


very interesting.

Magnesium block would be a little pricey don't you think?
well, it wouldn't be straight magnesium, it would be a magnesium alloy.

and ask VW how expensive it is, they had a magnesium alloy block in the bug for it's entire run from WW2 all the way up to the last one rolling off the line in brazil a few years ago.

one note, the colors are beautiful when it catches on fire.

hmm some interesting comparisons ... this discussion feels really similar to the ej20 vs 46g3 .. (why can the 4g63 runs so much more boost and higher A/F w/o detonation?)


i see think 210 is a pipe dream 180 maybe
2 points
Subaru is moving away from the market that was perfect for the n/a ej25 (the base outback) where the low end torque was more valuable than high hp

for 90% of the American consumers HP is a marketing number (bigger is better). 250 is too small for the LGT to compete with its competitors and 300 has become too small for the STI

I still think that most people here miss the fact that Subaru makes Sensible sedans and wagons that can drive in all weather conditions safely.

The base models need to compete with the lower end cars from the other makers, after they apply all their options, which AWD has to be the last or not even considered for the lower market.

As for the others, well the mid level Subaru's are all speed demons; All of them.

Most sports cars cannot accelerate as fast as a WRX or a LGT, Forester or Outback XT. Some can and they all cost 2 to 3 times what the subaru does similarly equipt. Sure there are riced cars that can blow a WRX off the road, when it is dry out, but almost nothing without being a premium brand comes close to the performance of a WRX ...

Subaru will in all likelyhood continue to evolve their cars, they have a niche in the lower end, but as they must cover the AWD costs and such they include all the options and make the other brands of cars look less favourable when similarly equipt. This is a bit of a marketing nightmare as people rarely see this until they are in the other dealerships and going over the competitions cars. Few would then consider a Subaru and then come in for a look. More likely it is person like me who go in looking at a more expensive Subaru only to find that one can't afford the higher payments and then considers the entry level cars.

Now Subaru has that entry rocket car market satisfyed and now has turned to capturing some of the premium market. The Tribeca is a foot into the Truck SUV minvan segment and the Outback VDC while having been here for awhile is not considered a threat by the other manufactures. It is after all just a station wagon with a huge price tag. After this though Subaru will have to look at the entry level and maybe a micro like the fourtwo or fourfour, think and smart vehicles. The R1 R2 might make it's way over here soon.