2011 Legacy GT - Advice Please

Hi All,

I have a 2011 spec Legacy GT and am experiencing very high fuel consumption with this car. I have taken it back to Subaru dealer a few times and they kept the car for almost a month to test but cannot resolve my issue. They keep stating that Subaru turbo model cars do have high fuel consumption. I am getting around 320km to a 54lt tankfill (95RON). Thats pretty lame I would say. I am NOT driving this car hard at all and seldom use the S#. I recently did a long trip test (about 200km) and only managed to bring it down to 10.6l/100km. I was driving very conservatively.

I have been researching for the last 3-4 months and came across some interesting reads on this car. I was hoping that some expert on this forum would be able to confirm/explain my conclusions I found:

1. Subaru has adopted a new design for the turbo location where it now placed at the centre front. This now means the header lengths are equal. (Not much scooby rumble).
2. The turbo on this model is similar to that of the WRX (if not the same)
3. With that said, it would then force Subaru marketting to de-tune this car as it would not look lucrative in the market to have the power output equal to that of its sports models. This would mean the ECU is programmed to limit this car's performance.
4. The exhaust system including the downpipe is restrictive thereby force creating the turbo lag we notice.

I have had this car for a year now (bought in Oct 2010 - but its a 2011 spec with the b/t handsfree and folding mirrors) and have to make a decision regarding going forward. Here in SA Subaru have become extremely paranoid wrt to warranty. If any mods are done on the car, they invalidate the warranty in completeness - which means not even the regular services are covered!!

Can any1 share some light in this matter? It would be highly appreciative.

Thanks in advance
Naseem
(Naseem.Ismail@telkomsa.net)

References:
www.mrtperformance.au

Originally Posted by Naseem

Hi All,

I have a 2011 spec Legacy GT and am experiencing very high fuel consumption with this car. I have taken it back to Subaru dealer a few times and they kept the car for almost a month to test but cannot resolve my issue. They keep stating that Subaru turbo model cars do have high fuel consumption. I am getting around 320km to a 54lt tankfill (95RON). Thats pretty lame I would say. I am NOT driving this car hard at all and seldom use the S#. I recently did a long trip test (about 200km) and only managed to bring it down to 10.6l/100km. I was driving very conservatively.

I have been researching for the last 3-4 months and came across some interesting reads on this car. I was hoping that some expert on this forum would be able to confirm/explain my conclusions I found:

1. Subaru has adopted a new design for the turbo location where it now placed at the centre front. This now means the header lengths are equal. (Not much scooby rumble). true
2. The turbo on this model is similar to that of the WRX (if not the same) i think so, but not 100%
3. With that said, it would then force Subaru marketting to de-tune this car as it would not look lucrative in the market to have the power output equal to that of its sports models. This would mean the ECU is programmed to limit this car's performance. the ecu is programmed to reduce power in 1st and 2nd gears. If anything, I think Subaru under-rated this car. You have people putting down 219-258 HP stock.
4. The exhaust system including the downpipe is restrictive thereby force creating the turbo lag we notice. I don't notice much turbo lag, but I don't have a whole lot of experience with turbos.

I have had this car for a year now (bought in Oct 2010 - but its a 2011 spec with the b/t handsfree and folding mirrors) and have to make a decision regarding going forward. Here in SA Subaru have become extremely paranoid wrt to warranty. If any mods are done on the car, they invalidate the warranty in completeness - which means not even the regular services are covered!!

Can any1 share some light in this matter? It would be highly appreciative.

Thanks in advance
Naseem
(Naseem.Ismail@telkomsa.net)

References:
www.mrtperformance.au

I'm not sure what your #'s convert to in mpg, so I can't comment on if they seem normal or not. FWIW, I reset my trip computer almost exactly 350 miles ago, and the avg MPG, computed by the car, is 17.1, 100% city driving.

Quick math says less than 14mpg

Originally Posted by Naseem

1. Subaru has adopted a new design for the turbo location where it now placed at the centre front. This now means the header lengths are equal. (Not much scooby rumble).

Correct. If you look at some of the downpipe install threads on this forum you can see some pictures of the whole exhaust system in various stages of disassembly. The trade off for the noise with those equal length headers is more power. The new turbo location gives us that power earlier.

2. The turbo on this model is similar to that of the WRX (if not the same)

Similar. It's a VF54. A bit smaller.

3. With that said, it would then force Subaru marketting to de-tune this car as it would not look lucrative in the market to have the power output equal to that of its sports models. This would mean the ECU is programmed to limit this car's performance.

Probably. It is dramatically detuned. Changing the tune while adding no hardware will give you a HUGE increase in low end torque. Search this forum for "dyno" and you'll get an idea for what can be gained. We can only speculate on Subaru's reasons for tuning various cars the way they do. Your guess is a common one, I'm inclined to agree.

4. The exhaust system including the downpipe is restrictive thereby force creating the turbo lag we notice.

1/2 right. The stock catback is very restrictive. The exhaust is the first major bottle neck to performance tuning once you start going down that route. I don't think you're quite right on the turbo lag. For starters, we don't really have turbo lag. We hit peak boost very early, in both stock and tuned form.

I have had this car for a year now (bought in Oct 2010 - but its a 2011 spec with the b/t handsfree and folding mirrors) and have to make a decision regarding going forward. Here in SA Subaru have become extremely paranoid wrt to warranty. If any mods are done on the car, they invalidate the warranty in completeness - which means not even the regular services are covered!!

Well... if you really don't like the car and you don't want to mod it such that you'll actually like it for whatever reason, it's hard to make an argument to stay in it (other than financial).

Also, 14mpg is pretty low. I'd have to seriously romp on my car to get that kind of mileage. Average for me is in the low 20 mpg's.

Also, also... did you say "spec"? As in spec b?

Originally Posted by Slider

Quick math says less than 14mpg

Ouch

Daily driving I get 22mpg; went to the beach this summer I got 32mpg (Highways). I would say my driving style is "spirited".

Take it for what it is worth in your research

When I'm staying off my turbo I can manage about 20 mpg city. When I'm boosting around every corner like I usually am I am at 13 mpg at worst. Stage 2 protune 93 oct.

Hi guys. Many thanks for the replies and info. I really do appreciate it.
I'm getting abt 6.5kpl which is about 15.3mpg (according to the conversion formular)
Howmany miles do u guys normally get to a tank? I'm sure what I am getting isnt normal. My current avg kpl reading on the car is 18.0. You guys seem to me getting much better than me with the lower 93 RON fuel.

Thanks for the technical tips, Surly. I will do some research on the forum articles. I am very convinced that my car can perform much much better with just a few corrective mods. And that not being drastic mods. But alas any mods here in SA makes the agents behave like cry babies. Yet they wont offer any worthwhile extras to their vehicles. (I've had to import my bootlip spoiler, USB kit and Homelink compass mirror from the USA). I dont know what u mean when u say "it's hard to make an argument to stay in it (other than financial)". Are u suggesting that I trade the car in? I actually do like this car's looks and features. I may just have a badly tuned vehicle. I almost at making a decision to tell SubaruSA to stuff their warranty up their a@!$ and do a complete turbo back 3" exhaust and a chip remap. Thats all I feel this car needs to start behaving properly.

I am not sure what "spec b" entails but the only diff with the 2010 and 2011 is the folding mirrors and bluetooth telephone kit, which is what I got. Other than that I think the cars are the same.

Thanks again guys.

Naseem

Originally Posted by SuberManGT

When I'm staying off my turbo I can manage about 20 mpg city. When I'm boosting around every corner like I usually am I am at 13 mpg at worst. Stage 2 protune 93 oct.

WTF??? I drive my car like I stole it and I get 17mpg in town. Stage 2. I can't imagine getting 13 unless I was competing at the local SCCA meet AND only competing

Originally Posted by Naseem

You guys seem to me getting much better than me with the lower 93 RON fuel.

95 RON = 91 US octane. 98 RON = 93 US octane.

http://hondaswap.com/reference-mater...ratings-59435/

Hmmm I didnt know that abt US fuel. Perhaps its the fuel then - but I seriously doubt that!!

Any ideas what I could ask the agents to check for?

I consistently get 22-23 MPG and I drive 99.8% city. I've never driven mine to sputtering empty but when I get 350 miles on the trip ODO or see the fuel light I usually fill up.

Good luck with your issue. Might want to take a journey to stage 1 or 2 and have a protune, the tuners might be able to find an issue?

Do you guys use the on board computer to gauge your mileage or you calculate by hand?

Hey Nas, do you know if your petroleum is imported pre or post refinery?

Man, everyone seems to get really low average here.

I get 24.6 MPG average, city/highway and on the weekends I tear up the canyons at 4-6K RPM and 15PSI boost.