Non-Turbo Acceleration

[CTSnowdog]

Hi! Are there any relatively inexpensive upgrades to get more power out of a non-turbo 08 Legacy 2.5i SE Auto that won't void the warranty? Maybe a K&N filter or something?

 

It's a great handling car, but sometimes I'm reluctant to pass other cars for safety reasons. SportShift helps a bit, but not always enough. I know it's not a turbo or an H6, but it could use a little more oomph.

 

Thanks!

[DarkOblivion000]

I'd tell you to drop it into 3rd and hit the gas but poop, you have an auto.

 

drop in filter or CAI/SRI, lightweight crank pulley, those are cheap. you won't get too much of a performance difference though.

[smushybrain]

I have the AVO panel filter and I like it a lot. I don't like the K&N filters because of the fact that they have to be oiled and our MAF sensors have the reputation of being very temperamental.

 

Other than that look around in this forum. You'll see that there are a few things that people recommend like the lightweight crank pulley, throttle body spacer, DIY intake piping, any axle-back exhaust that fits the GT will fit the 2.5i, etc...

 

Most people will recommend suspension upgrades and lighter wheels and better tires, too.

[CTSnowdog]

Thanks for the suggestons. Sometimes I used sport mode on the tranny, but is changing gears at 4,500-5,000 RPMs going to cause premature wear to my engine?

[whitetiger]

intake and exhaust wont do squat for the 2.5i motor. 5hp tops, which you can barely feel if at all. the 2.5i legacy is slow, especially in automatic. just somthing you are gonna have to live with, unless you want to spend several thousand on turbo kits/engine swaps, or trade in for a LGT.

[DarkOblivion000]

intake and exhaust wont do squat for the 2.5i motor. 5hp tops, which you can barely feel if at all. the 2.5i legacy is slow, especially in automatic. just somthing you are gonna have to live with, unless you want to spend several thousand on turbo kits/engine swaps, or trade in for a LGT.

 

Gees you are so constructive.

 

People have said they feel better performance from a z pipe instead of the stock air piping. See below

http://legacygt.com/forums/showthread.php?t=25695&page=48

[whitetiger]

Gees you are so constructive.

 

People have said they feel better performance from a z pipe instead of the stock air piping. See below

http://legacygt.com/forums/showthread.php?t=25695&page=48

 

 

its all in their heads. I/E mods dont do much, especially with out a tune. show me a dyno that says that z-pipe makes more than 5 hp peak.

 

what do you want to hear from me? that the 2.5i can make loads of power from bolt-ons? be more realistic.

[smushybrain]

intake and exhaust wont do squat for the 2.5i motor. 5hp tops, which you can barely feel if at all. the 2.5i legacy is slow, especially in automatic. just somthing you are gonna have to live with, unless you want to spend several thousand on turbo kits/engine swaps, or trade in for a LGT.

 

Slow is a very relative term. Yes our cars are slower than the Legacy GT and many other "fast" cars out there you'll get no argument from me on that. However, I've definitely driven slower (and less fun to drive) cars. How often to you really get to utilize a fast car's potential on public roads, anyway?

 

Many of us purchased our non-turbo Subarus because they run happily on 87 octane, still have a good AWD system, were cheaper up front than a Legacy GT and were still nicer and more reliable than a lot of other cars in the price range.

 

To get back to the point, though...

 

To the OP: You'll never make your 2.5i as fast as a GT (people like to bring this up over and over again here because it *is* technically a website for the GT) but anything you can do to make it breathe better (intake/exhaust) and free up some existing horsepower (lightweight pulley) will make it more fun to drive. Don't expect miracles but have some fun with your car.

[whitetiger]

But its also about hp per $. IMO, having owned a NA car in the past, not a singe power mod for the 2.5i is worth the money spent on it. And that goes back to the OP.

 

Are there any relatively inexpensive upgrades to get more power out of a non-turbo 08 Legacy 2.5i SE Auto that won't void the warranty?

 

The answer is no. I cant think of a singe bolt-on for the 2.5i that will net any reasonable gains. you cant talk about putting filters and pipes and stuff in, but you wont see any worht spending money on. Especially on a 4 speed auto trans.

[underground000]

Thanks for the suggestons. Sometimes I used sport mode on the tranny, but is changing gears at 4,500-5,000 RPMs going to cause premature wear to my engine?

 

does anyone know if only the 08+ 5eat GT have downshift rev match? cause if i N/A also have it wont cause as much wear on the tranny vs just downshifting

[DarkOblivion000]

its all in their heads. I/E mods dont do much, especially with out a tune. show me a dyno that says that z-pipe makes more than 5 hp peak.

 

I think the lightweight pulley frees up a bit of hp... more than 5? But I agree, you're not going to see any significant gains. All the little parts collectively will give you a noticeable performance boost, I believe. The auto trans also limits your ability to get up to the high RPM range to use any of that power, so it is likely you won't really see much of anything.

 

As for whether it's worth it... well that's up to the OP.

The OP is asking for suggestions on things he can do, not whether we think it's worth it or not. Notice nowhere in his original post does he ask "Is it worth it?"

 

I always feel like it's better to give information and let the OP decide whether it's worth it or not.

[smushybrain]

[...]As for whether it's worth it... well that's up to the OP.

The OP is asking for suggestions on things he can do, not whether we think it's worth it or not. Notice nowhere in his original post does he ask "Is it worth it?"

 

I always feel like it's better to give information and let the OP decide whether it's worth it or not.

 

I agree completely. To me, a few dollars spent making my car look, sound and perform better are worth it... to others it may not be. I already know it won't be as fast as a WRX or Legacy GT... but it's already fast enough for my commute. I don't need 400 whp to hit (or exceed) 65mph on the highway...

[whitetiger]

I think the lightweight pulley frees up a bit of hp... more than 5?

 

yeah, you wish. not even half that. It certianly does not make HP

 

But I agree, you're not going to see any significant gains. All the little parts collectively will give you a noticeable performance boost, I believe.

 

alot less than you think. in some cases, like exhuast parts, it will make the car slower. N/A need some back preassure to make low end torque. a exhaust upgrade on the wrong diameter pipe will actually sacrifice low end. ANd all of it is moot with out a tune, which last time i checked, was not available.

 

The auto trans also limits your ability to get up to the high RPM range to use any of that power, so it is likely you won't really see much of anything.

 

correct, he'll see nothing form the money he spends on power parts.

 

As for whether it's worth it... well that's up to the OP.

The OP is asking for suggestions on things he can do, not whether we think it's worth it or not. Notice nowhere in his original post does he ask "Is it worth it?"

 

And im saying that there is not much he can do. all he will do is maybe increase throttle response alittle (the 4eat trans will negate that), and make the car louder.

 

I always feel like it's better to give information and let the OP decide whether it's worth it or not.

 

Its best to be truthfull. i dont like to get people hopes up saying that if you do all this stuff you will see gains. Ive been downs the 4cyl N/A route before. I used to read all this stuff about how a cold air intake and exhaust and other bolt-ons would give you x amount of horsepower..ect. and when i bought all the stuff, it was such a let down, and i had a 5spd manual. Im trying to save the OP money, because ive been down his road before. power mods on the 2.5i N/A motor are not worth it, because they get you little or no gain.

[DarkOblivion000]

yeah, you wish. not even half that. It certianly does not make HP.

 

The lightweight pulley primarily makes throttle response better. But it should also decrease the amount of power lost through the drivetrain.

 

alot less than you think. in some cases, like exhuast parts, it will make the car slower. N/A need some back preassure to make low end torque. a exhaust upgrade on the wrong diameter pipe will actually sacrifice low end. ANd all of it is moot with out a tune, which last time i checked, was not available.

 

To the OP: This is true, the stock N/A exhaust is big enough to handle whatever is going to come out of the engine, so exhaust mods are a waste. And all mods are moot without a tune, also true.

 

The amount of money spent to just tune the ECU is probably not worth whatever effects the mods are going to give you... Simply said, the 2.5i is probably the worst kind of car to modify with a high compression N/A engine.

 

But many possible mods are listed in this thread. Pick a part, do your research, and then decide for yourself whether it's worth it or not. Most people with N/A Legacies go for suspension upgrades, as those see the most performance increases in our cars.

[Pawlwawl06]

Not inexpensive - but if you really want to be unique, go with the rallitek turbo kit (when available)

[whitetiger]

The lightweight pulley primarily makes throttle response better. But it should also decrease the amount of power lost through the drivetrain.

 

 

remember, he's got an automatic. no such thing as throttle response on the 4eat, and the drive train loss due to the trq converter is more than any pulley will ever fix. the pulley will do nothing for him. on a 5mt there may be some noticeable difference, but not on the 4eat. the OP has to understand that hes got the worst possible platform to start from. even the gearing is against him.

[Pawlwawl06]

remember, he's got an automatic. no such thing as throttle response on the 4eat, and the drive train loss due to the trq converter is more than any pulley will ever fix. the pulley will do nothing for him. on a 5mt there may be some noticeable difference, but not on the 4eat. the OP has to understand that hes got the worst possible platform to start from. even the gearing is against him.

 

I did notice a bit of increase in torque with my Group A lightweight pulley with my 5MT, but its mainly in the lower to mid RPMs.

[THE RZA]

yeah I say go with suspension mods on the car then you can have some real fun on some windy roads and hills. do sway bars, strut bar if you want its really useless but its available to do, springs are probably worth it more so than coilovers for 2.5i, if you can find someone with an LGT thats upgrading their brakes buy their stock ones off them it makes stopping much easier, hawk HPS pads as well. or do some visual things like clear your headlights, lip spoiler, tint the tails, tint your windows if you want. other than that just enjoy your extremely good looking above average midsize sedan.

[CTSnowdog]

I appreciate all the advice. By all means, I like the car (even with all the rattles, but that's another thread!). It's comfortable, it handles great, and it looks good. Great ride, awesome AWD, and it was a great value. 87 octane was the primary reason for skipping the turbo, and in some cases i'm kicking myself for not splurging. In some cases I miss the power of my former V6 Accord, but all-in-all my slow 2.5i is fun to drive. I'd just be happier with a little more torque. Actually, another gear would probably make a difference too (wonder what that 2010 CVT will be like).

 

So, what do you think... will changing gears at 4,500-5,000 rpms every now and then kill the engine?

[THE RZA]

i have 4EAT as well i always use either manual mode or sport mode, haven't had any problems, it shouldn't cause problems since it was designed for it, if you were doing manual mode and redlining every gear that may cause problems down the road

[DarkOblivion000]

remember, he's got an automatic. no such thing as throttle response on the 4eat, and the drive train loss due to the trq converter is more than any pulley will ever fix. the pulley will do nothing for him. on a 5mt there may be some noticeable difference, but not on the 4eat. the OP has to understand that hes got the worst possible platform to start from. even the gearing is against him.

 

Ah, I guess I underestimated the effect of the EAT on the power loss in the drivetrain.

 

So, what do you think... will changing gears at 4,500-5,000 rpms every now and then kill the engine?

 

I'm pretty sure the point of an automatic transmission is to stop you from hurting your engine by changing gears at the inappropriate times. So unless you pull the handbrake and hit the gas to try and launch or something I doubt you'd hurt anything. ECU's are not stupid; they're not going to self destruct on you.

[Imrac]

So, what do you think... will changing gears at 4,500-5,000 rpms every now and then kill the engine?

 

Well if you put your foot to the floor, the ECU should tell the engine to downshift and it will go all the way up to 6.3kish before shifting up (If you are really nailing it). My suggestion is just get use to the "manual" mode and get a feel for when the car would normally shift. When I first started using it, I would downshift to late and would sometimes drop 2 gears, going 25 and dropping into first is not great for you drive train.

 

Also I get improved gas millage. I average 1-3 mpg more then I do in standard drive mode, even when I am driving spiritedly. When on the free way I find 3rd gear more than enough omph for passing.

[DJ Wolf]

When I first started using it, I would downshift to late and would sometimes drop 2 gears, going 25 and dropping into first is not great for you drive train.

 

This seems to happen for me too when I try to downshift it coming to stops. I notice the car autodownshifts for you if you slow down to much such as coming to a stop. So lately if I use it, I just use it to control my upshifts and let the car downshift itself when coming to stops. Does this seem right?

[Ryouske]

Get a hybrid intake, pulley, throttle body spacer, and a few other small things and accel should increase. Your probably not going to gain any HP but your car should respond better.

[hadvw]

Was supposed to be "quick" summary: Sorry, man, unless you want to buy some snake oil, you're pretty much SOL. Your repeated concern about engine wear and warranty makes me want to say that you really don't want to do ANYTHING to your car. Enjoy it for what it is, or sell it for something else. The only thing that would make a noticeable difference would be a turbo/supercharger kit or NOS. All of which will DEFINITELY void your warranty, and DEFINITELY increase engine wear. A LOT.

 

K&N filters are great if you want to save on filter replacement costs, but it's long past the time when OEM air filters were a SIGNIFICANT restriction (similarly with exhausts, exhaust manifolds, etc). Look at the guys making 300+ hp with the stock airbox.

 

I know in the 80s, you could get maybe 30-40% improvement from an 81 hp VW Fox just by getting a different exhaust manifold, removing an exhaust ring restrictor, putting in a high-flow exhaust, K&N filter, a cam from a different VW and maybe a crank pulley. If you happened to have most of these parts lying around, it was a great upgrade. Of course, totally destroying all warranty in the process. Engines are MUCH more optimized today. They have to be to meet emissions and mpg standards. If they don't, they'll get crushed by the competition.

 

Long version:

note: I have an '05 5EAT LGT. Wife and I met up with sister + husband in Mesquite, NV in 2006 for road trip to Grand Canyon. They got an Outback 2.5i from the rental agency. Aside from the comfort issues (non-limited manual seats don't adjust as far as the power leather seats. I had trouble at 6'1". My b-in-law at 6'4" was much worse, even though he's skinny as rails), it was ok on level roads. We decided to use THEIR car for the trip to the GC, since it was the rental.

 

Once we got to the GC, we noticed the real problem: with 4 people in the car, there was no way to get any kind of decent oomph to pass a delivery truck on a large uphill road. We were literally scared to try it. And my sister drives a '96 2.0l Jetta (5MT, though) which won't set any records for power. We were stuck going 35-45 behind the truck. All this to say: WOW, the 2.5i is a gutless wonder in the legacy/outback with 4EAT! Heck, I could hit 115 mph in my '84 Jetta GLI with headers (maybe 95-100 hp) and 5MT with 4 people in the car. Yeah, I've probably been subject to the "gradual" increase of horsepower in the average car (and my cars *), so I've forgotten just how slow the GLI would feel today. But, I wonder if the 2.5i could even get to 115-120 mph with 4 people?

 

Also, let me chime in with the other posters here: I've been down the 4-cyl, NA route. The aforementioned '84 Jetta GLI, and a '90 GTi 16v. Heck, even my '94 Corrado VR6 (not a 4-cyl, but same idea). After all the chips, cold-air intakes, higher-flow exhaust, headers, etc.. it was way more pain/$$$ than it was worth. Chips (aka tune for the 2.5i) in the 16v and VR6 did a little but in turn required 92 octane - something you want to avoid. Cold air intake did almost nothing.

 

Unless you're willing to live with jet-engine noise, messing with the exhaust won't help. With help, I made my own exhaust for the 16v, and when it was REALLY open, it felt like the car got up to 150-155 hp, especially top end. But, I got headaches going across town. Had to quiet it down, and that took most of the extra power back.

 

The only thing that helped with the Corrado was the supercharger. And that was unreliable as heck. And of course, there were no warranties to speak of on any of these cars.

 

* all my cars:

-84 Jetta GLI (headers, maybe 95-100 hp?)

-90 GTi 16v (chip, exhaust, air intake - maybe 140-145 hp?)

-94 Corrado VR6 (supercharger around 8-9 psi, lots of other mods, maybe 240-260 hp?)

-05 Legacy GT (TDC stage 2, maybe 300 hp?)