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SteVTEC 04-04-2004 07:22 PM

Anybody have detailed info on the 3.0 engine?
This if from those PDFs that are stickied.


250 HP @ 6600 rpm
219 lb-ft @ 4200 rpm
10.7:1 CR (91 octane fuel required)

Aluminum-alloy cylinder heads with double overhead chain-driven camshafts (DOHC), four valves per cylinder, Subaru Active Valve Control System (AVCS) variable valve timing and Subaru Active Valve Lift System (AVLS) variable valve lift
It looks like this is similar to Honda's i-VTEC and Toyota's VVTL-i, since it varies both cam phase angle (AVCS) and valve lift (AVLS). I'm just curious if anybody knows how it works. As in, whether it's on just the intake side, just exhaust, or both. What range it will adjust through. And do the cam lobes have a gradient to them so that if you slide the cam laterally the valves will follow a higher lift portion of the cam lobe (similar to Porsche VarioCam). Or is it a different lobe altogether (like Honda VTEC or Toyota's VVTL-i)?

I think most of us here will be going for the turbo anyways, but I'm a bit disappointed. I would have liked to see maybe a 3.3-3.5L engine with beefier torque in the low-end and mid-range. Instead this is a top-end beast engine. With peak power not coming up until 6600 rpm, you'll pretty much need to be winding this sucker out to get full performance out of it. And unless the redline is set somewhere well north of 7000 rpm, you'll never be able to make full use of this power. i.e...the engine will have plenty of pull at redline, but will run out of revs before it runs out of pull forcing a shift before it's really optimal. I think in a car like this, a torquier "more power sooner" style of engine would be more appropriate, but this should still be plenty of thrust for most folks I guess.

Also, I didn't see any mention of a variable intake manifold. I wonder if it has one or not? That would certainly help a ton as far as keeping intake velocity up at low revs and generating decent low-end torque. And I wonder when "VTEC kicks in" LOL.


SUBE555 04-04-2004 08:10 PM

At this moment not a huge deal of information is known on the 3.0L H6 EZ30R (2nd generation) engine that will now include AVCS and AVLS systems to help improve performance. It will also now have headers (IIRC I think the first EZ30 generation had a single exhaust port from which each cylinder would feed in each head.)

Here is some info straight from the JDM site sent through Babelfish:
Engine technology of the world where it seeks power, seeks smooth feeling, and, seeks the decrease of environmental load and evolves. The history, now bears fruit in the power unit one. SUBARU BOXER6. Furthermore it reforms the natural nature, "complete rotary balance theoretically," vivid power and rich torque, fusing the fuel economy waste gas efficiency which is superior in the higher-order origin. The happiness ? that high efficiency unites deep organic function, has not experienced so far is produced.

Light weight, the compact, low center of gravity, it is low the vibration, high rigidity. As a sport unit, how many ones the horizontal opposition engine which has the nature which is superior. The challenge whose SUBARU which as power unit of ideal considers this horizontal opposition engine, continues to adhere is new. That, the horizontal opposition 6 cylinder engine which is loaded onto 3.0R [ SUBARU BOXER6 ], is EZ30-R. The horizontal opposition 6 cylinder engine which has the rotary balance which is called perfection theoretically. We pursued the unlimited possibility, poured the technology which even luxury can be said. Covers entire area due to the independent 3 port exhaust and with light weight conversion the adoption etc. raises the AVCS+ direct variable valve lift and exhaust efficiency of the resin make intake manifold which which makes inhalation resistance decrease, actualizing the feeling which power it improves and is refined and. So far smoothness and ????? which are not it evolved as the next generation power unit which it had. With other engine type it is not obtained, with upper quality functional feeling. The rich torque which from in any speed limits according to intention of the driver keeps accelerating. And, the environmental efficiency which is superior. The power unit which achieves the efficiency which is required at high dimension, furthermore heart of the driver even the sensitivity to echo it has. It meaning that that is SUBARU BOXER6, it does.

The rotary balance to which first merit of the horizontal opposition 6 cylinder engine, is called perfection theoretically and is superior. The cylinder can each turn, 3 as for the horizontal opposition 6 cylinder engine which had the structure which lines up horizontally, power from 6 these pistons which are divided into left and right doing almost balance completely, in order to join to the crankshaft, as for the crankshaft balance well on left and right. You bear revolution feeling where this is superior, in addition to the fact that the vibrations are few, quality quite you can blow smoothly to riding taste and high revolution ????? which rises being to make running possible, you do. In addition, as for the engine which is weight ones when being loaded onto the vehicle, in order to produce big effect on maneuverability, being the light weight compact is required. SUBARU BOXER6 actualizing the top-level lightweight design even in the world as 6 cylinder engines. Also engine total length, has left in approximately 20mm rise the horizontal opposition 4 cylinder engine (EJ20) with in comparison. The thorough pursuit for the this light weight compact, "total height is low in comparison with V type 6 cylinder engine, the handling where you pull out horizontal total length is short in comparison with the serial 6 cylinder engines" opposition 6 cylinder engine natural nature to full, low center of gravity and depends on the weight balance which is superior and excels is made possible. Maneuverability while it is quite smooth revolution and mind. Catching the heart of the driver in all respects, efficiency of the ideal which you do not separate, while being born, being to have, it does the horizontal opposition 6 cylinder engine.

From the idling limits to the high rotary limits, SUBARU BOXER6 where you can obtain as desired acceleration in all territories. Those where it is adopted in order furthermore to pull out this potential, inhalation variable valve timing (AVCS) are + inhalation variable valve lift mechanism. In combination with valve timing and the valve lift quantity of inhalation side to operational circumstance, as by the fact that it controls optimumly variably, it improves the torque at entire area, fuel consumption and occurrence of the emission are held down to minimum. In order to utilize the compact design which is the merit of the horizontal opposition engine, as for valve lift mechanism not to be the rocker arm system which is used generally, adopting light weight compact direct push system. The valve lifter of inhalation side - we to be constituted from the tappet of 2 layer, to adjust to accelerator opening and rpm, variable control the valve lift quantity. Simultaneously with that, also valve timing of the air inlet cam is controlled optimumly variably. For example, by the fact that the low-speed time the valve lift it is small, controls valve timing slowly, improvement combustion efficiency. In addition at the time and the like of sport travelling, the valve lift it is large, adjusts valve timing ahead of time and by the fact that inhalation efficiency is raised, high efficiency actualizing power management at entire area. It is compatible the strong running and environmental efficiency in the higher-order origin.
One thing not advertised is that the JDM/EDM powerplant makes about 247chp, but has a slight bit more torque. You can see the torque numbers have been sacrificed a little bit for that 'peak' hp number for marketing purposes. At least on paper.

SteVTEC 04-04-2004 10:14 PM

thanks for the copy/paste! LOL, you can definitely tell that was translated from something other than English. the variable lift/timing is on the intake side only. That's good because that's where it's most effective. Didn't see any variable length/path runner mechanism in the intake manifold so that's sorta a bummer, but as long as the cam advance / phasing angle is pretty optimized it should be able to give some decent low-end torque. Should be better than the 2.5GT at least due to no turbo lag. And it's tough to see in the picture, but there does seem to be 3 lobes on the intake cam vs 2 on the exhaust cam. So that would make it a cam lobe switching system like a VTEC. There's no irregularities on the torque curve, so wherever the transition is is not apparent. But that's good. It means the "non-VTEC" cam profile is aggressive enough that you're not losing anything down low. Some Honda VTEC systems are setup more for economy on the non-VTEC lobes and you lose a bunch of torque. That's where the "VTEC hump" comes from.

Thanks again for the info!


SUBE555 04-04-2004 10:54 PM

I'll admit, it's very hard to tell much of anything right now, for one, their pics just aren't big enough to pull any sort of details out (wish it was about twice as big), but take a VERY close look at the two cams pictured (top and bottom on the near side.) The top (intake) cam just looks a little different, it's not too easy, but the follower may look a little different as well. I'm trying to get more details, but everything is sketchy at best at this point.

.............. Upon searching and searching more on the JDM site, I have found some new stuff that corroborates that unique single intake cam with dual profiles...

...once again, more Babelfish :lol: (At least it's better than my translating skills. :D

Here's the Non-Babelfish Link

I hope these pictures help a little. I'm not quite sure how the changeover is made, but I'll keep looking around when time permits (back to do some Kinematics on gears for class.)

I think aside from some small exhaust and intake modifications, the majority of power that could be had out of the EZ30 would be from both intake tuning and headwork including cams.

The fact of the matter is that the EJ25 turbo will produce more power from a medial driving rpm straight through redline (even though the GT's is 500rpm less.) I'll try and pull up the old discussion of the EJ25 turbo versus EZ30R NA engine.

SteVTEC 04-04-2004 11:22 PM

ah, sweetness! Okay yeah I've seen that same type of setup before. It's just like Porsche's VarioCam Plus. Take a look at this.

Look familiar? Subaru is using the same exact type of setup with the variable tappet - they did mention a "2 layer tappet". That's pretty darn cool. So now when the Honda guys say that Subaru "copied" VTEC (and they will), 3.0 owners can say "NO" and that it's functionally equivalent to Porsche VarioCam Plus. hehehe

BTW, there is a ton of great tech at that AutoZine site. I've learned a ton from there.

SteVTEC 04-04-2004 11:27 PM


Originally Posted by SUBE555
The fact of the matter is that the EJ25 turbo will produce more power from a medial driving rpm straight through redline (even though the GT's is 500rpm less.) I'll try and pull up the old discussion of the EJ25 turbo versus EZ30R NA engine.

Oh yeah I know that - no question there.

I'm just curious for curiosity's sake is all. ;)

But still, for crawling around through the woods and off-road stuff, along with towing, the 3.0 would probably be a little better than an EJ25 with some turbo lag. Plus some people just prefer N/A engines. They're simpler so there's less that can go wrong. A lot of people have the perception that turbo engines aren't as reliable. They're just as reliable if properly cared for, but some people aren't interested in doing anything more than the bare minimum. I think it's a wise move on Subaru's part to keep a 6-cylinder N/A in the lineup.

SUBE555 04-05-2004 12:11 AM

I actually like the NA engines rather well and would love a monster naturally aspirated engine that has both low-end and power up top, but it would be far less cost effective than just some minor tuning on an EJ25 turbo engine. There's always that incling though. :evil:

Now I know AVCS can't be used on the SOHC engine, but I wonder about that AVLS to improve power up top (as it drops off too early on the current Phase II cam tune)? I also wonder if they can produce a nice equal-length header for the twin-scroll turbos, why can't they make a nice equal-length header for the NA cars? Combine that header, new intake manifold with plenum and runners directly facing the throttle-body, and AVLS to improve power and efficiency. Hmm, I wonder what the EJ20R in the 2.0R all uses besides some nice AVCS DOHC heads...
Might lose part of that nice boxer tone, but I think we'd suffer for more NA ponies. :)

Okay, back to the EZ30R. ;)

SteVTEC 04-05-2004 08:17 AM

Actually you can use AVCS (cam-phasing) in SOHC engines. It's not as effective as it could be in a DOHC, but it still works. Ford is using it on the new base SOHC V8 in the '05 Mustang, and on the 5.4L Triton in their trucks. I don't recall the before/after specs on the 5.4, but on the Mustang 4.6 power is up from 260hp @ 5200rpm to 300hp @ 6000 rpm I think - a lot more top-end. They also went with a 3-valve head (2 intake, 1 exhaust) and did a few other tweaks as well.

The critical part of a cam phaser setup is tuning the intake valve open and closure based on RPM and load - resonance tuning so that you get maximum volumetric efficiency. Once you get the maximum amount of air volume in, it's going to get out one way or another, so tuning the exhaust cams isn't as critical. This is why most manufacturers go with variable timing mostly only on the intake side - the benefits of tuning the exhaust side probably isn't worth the expense and complexity. Unless it's a really high-end car with a premium price tag.

SteVTEC 04-05-2004 08:18 AM


Originally Posted by SUBE555

hmmm....I wonder if there's a chart like this floating around for the 2.5GT.

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