Jump to content
LegacyGT.com

3.0R Legacy Information


msuperbauer

Recommended Posts

OK, let me fill you in:

 

H6 advantages:

 

  • More torque at low rpm.
  • Generally, better mileage.

Is there evidence of this? Every dyno plot I have seen comparing the two has the 2.5T's torque curve above the 3.0 for all RPMs, but then again they usually start at 2000ish. Those torque curves do start below boost, however.

 

Also, how do you back up the better mileage? I see 17/24 for auto 3.0R and 18/24 for auto 2.5GT at Edmunds, which looks like pretty much a tie. My 08 OB 2.5i limited 4AT allegedly gets 20/26 but in my real-world driving it does not get better average mileage than my 05 2.5GT 5MT that allegedly gets a lower 19/25.

 

I'm just curious because I keep hearing this about torque.

 

--Lee

Link to comment
Share on other sites

  • Replies 50
  • Created
  • Last Reply
Is there evidence of this? Every dyno plot I have seen comparing the two has the 2.5T's torque curve above the 3.0 for all RPMs, but then again they usually start at 2000ish. Those torque curves do start below boost, however.//
Do you have a plot of a stock 2.5T with 5EAT? I've never been able to find one, except at a tuner out in Denver so it was at 5,000 feet elevation: this would certainly change the peak, not sure about the shape of the curve.But you get the idea.

 

I ran my H6 on a dyno at TDC, (on Regular fuel). He only got it up to 6,000 rpm (redline is 7,000) and failed when he tried to run a co-worker's 5EAT LGT. My goal was to have back to back runs on the same dyno of a 5EAT LGT and a 5EAT 3.0R for the edification of the community. But TDC foiled my plans, and now I don't care! So if these graphs skewer your goat, go do your own!

 

What is not in doubt is that the flat torque curve in the H6 makes it a very easy car to drive near the limit for extended periods.

 

Stock H6 @ TDC

http://dervish.smugmug.com/photos/419014889_7ZNb6-L.jpg

 

Stock 05 LGT 5EAT @ Dencer (I think).

http://dervish.smugmug.com/photos/419014943_qsLMi-L.jpg

Who Dares Wins

スバル

Link to comment
Share on other sites

so with the H6 at sea level and the 2.5T a 5000ft they are putting out nearly exactly the same whp?? Could this be something to do with the fact its an obw not a legacy?? I do like the flatness of the torque curve though. Looks like an easy car to drive in mt form, not that anyone in this country would know.:rolleyes:
Link to comment
Share on other sites

Did you work hard to find the worst possible LGT dyno plot ever? Cobb's plot shows stock LGT wheel torque above 140ft-lbs at 4500ft. Is that wrong?

 

http://www.legacygt.com/forums/attachment.php?attachmentid=59958&stc=1&d=1226940477

cobb.gif.b1ff1b7efbcea8a8d2b39d83cba5b940.gif

Link to comment
Share on other sites

so with the H6 at sea level and the 2.5T a 5000ft they are putting out nearly exactly the same whp?? Could this be something to do with the fact its an obw not a legacy?? I do like the flatness of the torque curve though. Looks like an easy car to drive in mt form, not that anyone in this country would know.:rolleyes:
I'd guess the differences in dyno and elevation are more significant than car-to-car differences, but who knows? I seem to be the only one to ever put an H6 on a dyno, and I've posted many times asking for a plot from a stock LGT 5EAT. There was so much "butt-dyno" talk here that I eventually offered to pay for a co-worker to dyno his 05 LGT 5EAT myself if he would bring it up to TDC. But TDC couldn't git 'er done.

 

 

 

Did you work hard to find the worst possible LGT dyno plot ever? Cobb's plot shows stock LGT wheel torque above 140ft-lbs at 4500ft. Is that wrong?

 

Nope. RTFP I've posted requests for stock LGT 5EAT dyno plots many, many times on this forum, since the H6 is only sold as 5EAT in the US.

 

I've driven a co-workers 5EAT LGT and my H6 back-to-back to see the difference myself, and moved on with the 09 WRX, so I'm done with that comparison. Subaru sells the 2.5T and 3.0R SpecB in Australia, so anyone who wants can look up the comparative performance data there. What's unknown about that is any output difference versus those sold here.

 

 

 

Who Dares Wins

スバル

Link to comment
Share on other sites

Both stock cars are at 140ish lbs of trq at 2200rpms. I agree the h6 is smoother but as far as early on power it loosk like they are within 10ftlbs of trq at 2k and the lgt is obviously higher by 3k.
You are comparing the Cobb numbers? Then you're comparing a manual shift to a 5EAT.

Who Dares Wins

スバル

Link to comment
Share on other sites

Are we talking about engines or transmissions?

 

Why would a 2.5T + 5EAT have half the torque of a 2.5T + 5MT at 2000rpm, yet somehow the 3.0 + 5EAT doesn't show this same tremendous inefficiency of the 5EAT. Are you saying the 3.0 has some torque peak near 2000 that perfectly balances out this 5EAT inefficiency? I just don't see how the dyno plots are really comparable as we don't know how they were done, probably different dyno manufacturers, etc.

 

My guess is the 3.0 does have more torque than the 2.5T well under 2000rpm, but certainly nowhere near the double that seems implied at 2000 by VVG's dyno plots.

 

Personally, I just have been quite disappointed with the 3.0 on loaners while doing my usual commute. Part of that is definitely 5EAT vs. my usual 5MT, but hey, with 3.0 you're stuck with 5EAT. On my home commute up the Route 2 hill through Arlington, 2.5T + 5MT will effortlessly accelerate from 65-75 in 5th whereas the 3.0 + 5EAT downshifts once or twice which seriously affect overall smoothness. In terms of fuel efficiency, on my commute, 2.5T + 5MT gets about 21-22mpg, 3.0 + 5EAT about 18-19. I was surprised as I had higher expectations for the H6.

 

To each his own...

Link to comment
Share on other sites

Are we talking about engines or transmissions?

 

Why would a 2.5T + 5EAT have half the torque of a 2.5T + 5MT at 2000rpm, yet somehow the 3.0 + 5EAT doesn't show this same tremendous inefficiency of the 5EAT. Are you saying the 3.0 has some torque peak near 2000 that perfectly balances out this 5EAT inefficiency? I just don't see how the dyno plots are really comparable as we don't know how they were done, probably different dyno manufacturers, etc.//

Until someone with a 5EAT LGT does a dyno run, we won't know.

 

But as I mentioned earlier, I've swapped cars back-to-back with a co-workers LGT 5EAT ,and the difference is small. The difference between my new WRX and either of the two is, well, not so small.:)

Who Dares Wins

スバル

Link to comment
Share on other sites

  • 2 weeks later...

I own a 3.0R spec B with SI drive / 5EAT. I love the car to death.....It is quite, quick when it needs to be, and my mileage sucks ass, but that's because of my lead foot ;)

 

Now, the thing with the torque is this (from what I have seen on the Subaru Japan curves) is the 3.0R torque is available below 2000, at about 1600 rpm, and once it's tapped, it is pretty linear up to 6000 rpm. Just my 2 cents.

Link to comment
Share on other sites

I have a 2009 3.0R Limited, now at about 4600 miles. I noticed this soon after I bought it: there is a rather loud whining noise when steering, most noticeable especially near full turn at low speed (for example while backing up and turning to exist from a parking spot). I am used with this happening in other cars too (I drove Toyota, Honda, etc), but this is more pronounced than in those cases. Does anyone experience something similar? I am considering going to the dealership to have the system checked, but I would like to have an idea about how (above) normal this steering pump noise is in other legacys before doing that.

 

Thanks

Link to comment
Share on other sites

  • 2 weeks later...
Having a timing chain over a belt is the biggest advantage. It should last the lifespan of the engine. I love the 3.0 in my Tribeca even though its a bit under powered for its weight. Not to mention the 3.0 engine is built in Japan and imported along with the Turbo 2.5, the N/A 2.5 engines are built here. Its a very expensive engine to build compared to the 2.5
Link to comment
Share on other sites

Alrighty, Thanks for all the great info, Upon further thought.. I use the car as a daily driver in a sales job (500+ miles a week) I realized I'd just be ruining the car over the next few years, so I drive the 2.5i Limited.. I liked it! Same great leather interior (not perforated, but great leather) same Harmon Kardon Sound system, same all wheel drive and reliability I want, and minus the 18" wheels the same look! So I went for it! and after 1 month and 1200 miles, I LOVE IT! When I feel the need for fast and crazy, I drive My VR6 Corrado.. Again, Thanks for all the info!
Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.




×
×
  • Create New...

Important Information

Terms of Use