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  #21  
Unread 31st December 2013, 05:41 AM
Bobam Bobam is offline
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Just my 10 c worth.
J's auto 01 foz gets 8.3 l/100k at 100kph-110kph @1.78 tons [weighbridge docket].
Towing 1.1ton [weighbridge again] pop top van @ 90-95kph it gets 16-18l/100k [very ouch].
The little 92kw 2.0lt motor just isn't really suited to towing this weight.
It is continually hunting between 4th and OD.
I thought maybe this box could remap itself after awhile but I was wrong.
Have achieved 7l/100k from my man 98 foz highway cruising at 90-95kph.
Roof racks kill fuel economy stone dead and are noisy.
Mine go off and on as required, which is never now as I can fit my rarely used mal in the back if I put the front pas seat all the way forward and a rag over the tail.
If doing lots of towing in lower powered cars/trucks etc we have run smaller diameter tyres. Same as adding a lower gear, naturally road speed is lower, although you will probably find if towing in hilly country the average road speed is actually higher.
regards
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  #22  
Unread 31st December 2013, 10:00 PM
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Gidday Bob

Happy New Year to you and yours, mate.

I reckon towing a 1.1 ton van behind a 2L SF would be stretching a friendship a bit far! My '93 Impreza would tow some incredible things at speed, but I don't know that I ever even looked at the fuel consumption - just assumed it would be terrible, and filled up as needed! Like the SF, with the EJ-18 donk in my Impreza it was just seriously underpowered.

SWMBO's 2.5L SH auto gets around 8.5L/100 kms with four adults on board and sitting on 100 to 110 kmh with the a/c and cruise control.

My SG with the 5MT/DR gets around 7.3L/100 kms with two adults up on the same road as the SH's measurement was done at the same mix of speeds and conditions. Roo2 has the aero roof bars permanently fitted. They aren't too noisy, and don't seem to add the drag/noise that the wire frame roof basket does.
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  #23  
Unread 1st January 2014, 12:58 AM
guzzla guzzla is offline
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Quote:
Originally Posted by Ratbag View Post
That's pretty impressive torque mate (225 Nm)! And at 3600 rpm. That's 400 rpm lower than the same torque figure from the EJ253 series II at 4000 rpm.
My relatively new Golf 90TSI 1.4L petrol engine has 200Nm of peak torque over a band from 1400rpm to 4000rpm. No stock 2.5L Forester can stay with it. It pulls like a diesel. It pulls up hills in 4th gear that is a bit taller than my Forester's in a way that the XT hasn't a hope in hell of doing. And I get down around 4.4L/100km fuel consumption under the same driving conditions as my 07 XT manual gives around mid 9's. It's amazing what the latest direct injection, variable valve lift & timing and turbo technology can do.
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  #24  
Unread 1st January 2014, 02:04 AM
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^ That's nice, Guzzla.

I guess the turbo 2.0L Forester donks are much the same.

One thing though ...

The EJ-253 has a more or less flat torque curve from around 1800 to over 6000 rpm.

How flat is the torque curve of your Golf engine?

According to this article, the torque band is 1500 to 3500 rpm. Is this the engine you are talking about?

Great fuel economy too. Nearly 20% better than the advertised figures ...

Of course, they are somewhat differently purposed cars, and that shape difference does add considerably to the fuel consumption of the larger car that's about 200 kgs heavier as well. However, under real life conditions, my MY06 N/A Fox has turned in 7.3L/100 kms. Not too bad for an old clunker that doesn't have a tiny turbo charged engine. Maybe that will help it remain in good condition for another couple of hundred thousand kms ... .

BTW, I can't understand why your 2007 XT has trouble going up hills in 4th.

Seems strange to me. My N/A 2006 5MT/DR has no difficulty at all in 5th on any hill I have yet encountered, let alone in 4th. Perhaps you could be just a little more specific so that we can all understand exactly what conditions you are talking about?

[EDIT]
I also note that the specs reckon your 2007 XT does 0-100 km/h in around 6 secs. This is just a tad faster than either the Golf or the N/A 2.5L Forester which are about the 9.5 sec mark ...

Perhaps we should add in the Abarth 2L V8 for comparison, at around 7 seconds 0-100 mph (IIRC) ... ?
Just while we are comparing horses, donkeys, asses and zebras ...
[end edit]

Last edited by Ratbag; 1st January 2014 at 03:01 AM. Reason: Obvious ...
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  #25  
Unread 1st January 2014, 05:09 AM
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No, not that engine. Mine is the latest generation of Golf engines released with the mk7 Golf. The specs sound the same as the mk6 - 90kW and 200Nm but the only thing the two engines share are the bore centres. The new one is a long stroke, alloy block with the fuel injection at the front and the exhaust manifold & turbo at the rear. VW have also gone back to belt drive for the cam shafts. It also has a wider peak torque band than the earlier engine - 1400rpm to 4000rpm and a wider peak power band from 5000rpm to 6000rpm. And it is more economical.

I drive my XT and Golf (the wife thinks it's hers but we all know differently don't we? As I tell her, I paid for it and she had better not rub those lovely alloys up against the kerb!) a lot every day. We have done 25,000km in the Golf in 6 months (we're taking it down to the Blue Mts for a 5 day break tomorrow). It's fascinating comparing the two vehicles and their different approaches to motoring.

My Forester has had the secondary airpump delete that affected all 2.5 turbo Subarus from 06-07 and the ECU retuned by Chip-Torque at the Gold Coast to get rid of the resultant code and on the dyno the peak power went up from 126kW to 142kW atw and torque from 320Nm to 370Nm atw. So more power especially above 3000rpm and over time I've noticed better economy around town but the same on the h'way. So it goes really well with what must be now around 190kW at the flywheel instead of the standard 169kW. But what still has me completely stumped is how competitive that 90kW Golf is. You are in the peak torque band almost as soon as that clutch is released and it just surges forward riding this peak torque band that must be as flat as the Nullarbor. I'm still not used to it. It's performance is very close to what our V6 Camry did.

There is a back road up the Toowoomba Range that not many people know about and one steep part requires coming out of a bend after a tricky spoon drain creek crossing and doing about 60km/h. In 4th gear at around 2000rpm in all vehicles (though the Camry had to cope with the tallest gearing and the Forester has the advantage of the shortest gearing) the Camry & Forester struggle to get up the hill. In fact I'd call it abusive to ask the Forester to do it. The Camry could go down to ridiculous revs and stay smooth. That's the lovely smooth V6 for you. The Golf just surges up that hill easy as anything, accelerating away and feels like there's a magic hand pushing you up. It left me shocked the first time it happened. Now if it was a faster corner at the bottom - say around 80km/h the Forester would have the revs and would be away. And here's another proof of torque. That 200Nm of flat torque gets the Golf up the Toowoomba Range easily in 6th gear which is a 46km/h per 1000rpm gear. It does it easier than the Forester can in its 40km/h per 1000rpm 5th or the Camry in its 41km/h per 1000rpm 5th gear. (Actually that's indicated - the real speed is 37km/h for the Forester and 45km/h for the Golf, the Camry had an accurate speedo).

While I really do love my Forester and intend keeping it for many years time has really moved on. The Golf has a lot more passenger room than the Forester (its 110mm longer wheelbase and extra 50mm of width see to that), it has 380L of luggage room compared with the Forester's 387L, it's ride and handling are just in another world as is its silence and the brakes are just not in another world they are from another universe. I have been is some highly modified Foresters but even their special Brembo set ups don't come near this.

You mentioned the Subaru performance claim of 6sec 0-100 for the XT. Wheels tested it at 6.6sec back in 2005. And yes, VW claim 9.3sec for 0-100 for my Golf. But Wheels in Dec 2013 just tested the auto version of it with the same claimed time at 8.4sec. But as you know in the real world driving it's useable torque that really plays a significant part in how we feel the performance of the car. But yes, really get up them and the XT Forester is in another performance league. Some passengers have been known to scream.

Fuel economy? Subaru claim a combined average for a 2007 XT manual Forester of 11.4L/100km. In the 248,000km of ownership I've averaged 9.3L/100km. I do plenty of h'way driving. VW claim 5.7L/100km combined for my Golf (the worst of any of the 1.4 petrol and 2.0 diesel versions) and 4.9L/100km in the extra urban cycle. Up to 25,000km I have averaged 5.3L/100km but nearly always get in the 4's on the h'way - in fact leave Toowoomba and 20km later at Helidon it is indicating an average of 3.7L/100km and that's from a cold start!. For example yesterday I visited my elderly parents at Redcliffe, north of Brisbane. The 351km return trip involved going through peak hour traffic in Brisbane both ways and about 30km of driving around Redcliffe itself. The Golf averaged 4.4L/100km. When I got home last night the MFD (multi function display) showed that I had done 351km & that it still had a remaining range of (get this!) 850km. And all this on a 50L tank! The other day I did fill it up with 50L when it was telling me that it still had a range of 65km so it obviously holds more. One guy on one of the two Golf forums I tend to follow now claims to have fitted 55.7L in his and it was still running. But for me 1200km is theoretically possible on a single 50L tank. I have done over a 1000km a couple of times. And this is a petrol, not a diesel. Even the mk5 & mk6 diesel Golf fanatics are a bit stunned by the results some of this new generation of Golf petrols are achieving.

Apologies for all these ranting on a Subaru forum, but I'm also still a Subaru fanatic too (especially SG Foresters - mine looks better than my Golf and who would ever think anyone would be praising the looks of a Subaru lol)

One last thing, I was a little concerned going back European, especially after the mk1 Golf I owned for 165,000km back in the late 70's (talk about crap Aussie assembly) but this new Golf I've got has been the most perfect car I've ever owned. Superb finish and build quality, NO rattles or buzzes and not one complaint. I hope that lasts.
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  #26  
Unread 6th October 2014, 08:04 PM
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Quote:
Originally Posted by Ratbag View Post
Speaking of the EJ-253, I discovered today that the inlet manifold in SWMBO's SH EJ-253 is about 1-2 inches higher than the one in Roo2. Interesting. The longer the inlet manifold, the higher the low down torque (in particular).
Heh Ratbag, do you have any info on how Subaru increased the power of the SG engine from 121kW to the 126kW on the SH? Torque went up a bit too. Subaru rated this engine at 127kW in the Liberty when it was introduced earlier but I assume it is the same engine. Are they both called the EJ-253? And if so, what was the EJ-252 (assuming there was one)?
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  #27  
Unread 7th October 2014, 12:04 AM
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Gidday Guzzla

Quote:
Heh Ratbag, do you have any info on how Subaru increased the power of the SG engine from 121kW to the 126kW on the SH? Torque went up a bit too. Subaru rated this engine at 127kW in the Liberty when it was introduced earlier but I assume it is the same engine.
Check out the Wikipedia article here:

http://en.wikipedia.org/wiki/Subaru_EJ_engine#EJ253

"I-Active valves (VVL intake side) on 06+ models which have ISO 173 hp (129 kW) @ 5600 rpm, 166 ftlbf (225 Nm) torque @ 4000 rpm. Compression ratio 10,0:1"

Keep in mind that all these figures are for the USA market. The engines they got are slightly different from the ones we got for any given model. e.g. the US market Forester apparently didn't get the EJ-253 until the year after we got it. Oz was a big beta test site, perhaps?

ALL of the Owner's Manuals I have downloaded are for US market vehicles. The OM for other markets do not appear to be available electronically. In major practical terms, this means that the term "dual range" never appears in the US market OMs ...

As for how Subaru changed the EJ-251 performance specs into those of the EJ-253, the answer is simple at an obvious level - i.e. the physical changes. Probably a good deal more complex at the ECU tune level.

Physical changes & Effects:

1) the heads and camshafts are different (the two inlet valves can follow either the same - or similar? - cam lobes, or one of them can be changed to follow a cam lobe with a different lift and profile by the ECU, instead of being identical at all rpm);

2) the valve trains are different (VVLT) - controlled by the ECU. Each of the two inlet valves can have a different valve lift (and presumably valve timing) at break points that are varied by the ECU dependent on engine speed, gear, engine load, etc

3) the inlet manifolds are different. The EJ-253 uses a MAF sensor instead of a MAP sensor, and this allows better control of the fuel:air mixture ratio under all conditions. It also has tumbler valves in the inlet manifolds, giving better swirl characteristics at low rpm, and therefore better and more efficient combustion. The EJ-253 in our SH has longer intake manifolds than the ones on my SG EJ-253. This will increase the torque and engine responsiveness a little.

For a description of the Subaru I-Active Valve Lift System (VVL{ift}T), see here:

http://drive2.subaru.com/Spring07_whatmakes.htm

The turbo engines use Subaru's VVCS (VVT{iming}T), described here:

http://drive2.subaru.com/Win05_WhatsInside.htm

Some manufacturers engines employ both of these in either turbo and/or N/A engines.

All the above physical changes allow the EJ-253 engine to have its torque characteristics optimised for both low revs and high revs simultaneously compared to the EJ-251. Mid-range revs are always "optimised" by default. The EJ-251 torque curve is much more like a classic inverted ski jump shape. The torque curve of the EJ-253 is pretty flat from 1,200 to 6,300 rpm.

What this means in practical terms is that the EJ-253 is getting around 80% of its maximum torque by about 1,200 rpm, and 90% by about 1,800 rpm. This difference is very noticeable in everyday driving situations. The EJ-253 torque curve stays above 90% until it hits its red line at about 6,300 rpm.

My understanding is that the EJ-251 has usable torque by about 2,200 rpm and the torque curve seriously drops away after about 5,000 rpm.

There are differences in the exhaust systems between the series I SG and series II SG, and again between the series II SG and series I SH which also uses the EJ-253 until the middle of 2010.

Quote:
Are they both called the EJ-253? And if so, what was the EJ-252 (assuming there was one)?
There was apparently an EJ-252 in the US market. See the Wikipedia article. I don't know if this engine was ever in any Oz DM car.

Yes, both are marked EJ-253 on the compliance plates, but with different engine suffixes. The engine block only has "EJ-25" cast into it, but again, the casting is different between the SG and the SH. I understand that the block is the same part number for the EJ-251 and EJ-253, which means that all the modifications are to the heads, cams, valve train, inlet and exhaust systems - and the ECU programming, of course. But if this is so, why are the block castings different between our two EJ-253 engines?

Taza is running an EJ-251 block and heads with an EJ-20 ECU running a piggy-back ECU which has been tuned for the EJ-251 IIRC. Even though his engine is N/A, it requires an ECU tune to fix the incompatibilities between the EJ-20 ECU and the EJ-251 motor. Doing this would also allow shifting the torque curve around a bit, and maybe altering its shape and extent by a little.

However, the things that allow for the ECU programming changes between the EJ-251 and the EJ-253 are all fairly major mechanical changes to the design of the inlet manifold system, the valve gear and camshafts, and probably the exhaust system. I don't know if the changes to the inlet valve lift has caused there to be changes to the exhaust valve timing and overall lift and cam profile parameters. It may have, is all I can say.
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  #28  
Unread 7th October 2014, 07:09 AM
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Quote:
Originally Posted by Ratbag View Post
"I-Active valves (VVL intake side) on 06+ models which have ISO 173 hp (129 kW) @ 5600 rpm, 166 ftlbf (225 Nm) torque @ 4000 rpm. Compression ratio 10,0:1"

Keep in mind that all these figures are for the USA market. The engines they got are slightly different from the ones we got for any given model. e.g. the US market Forester apparently didn't get the EJ-253 until the year after we got it. Oz was a big beta test site, perhaps?

ALL of the Owner's Manuals I have downloaded are for US market vehicles. The OM for other markets do not appear to be available electronically. In major practical terms, this means that the term "dual range" never appears in the US market OMs ...
Thanks Ratbag for the usual detailed information.

Yes, we can be almost certain that there are differences in tuning between the US and Aust market cars.

Information I have from Subaru Aust brochures, motor mags and web sites quote the series 1 SG at 112kW/223Nm (the Liberty/Outback got the same torque but 115kW from the same engine), the series 2 SG has 121kW/226Nm (Liberty/Outback the same) the series 1 SH has 126kW/229Nm (the Liberty/Outback had 127kW/226Nm and the new twin cam, chain drive FB engine in the series 2 SH and SJ has 126kW/235Nm (but only 123kW/229Nm in the Liberty/Outback).

I do remember that when the SH Forester was released I found a special release brochure from Subaru Australia that explained the many changes in quite a lot of detail, including just what was done to the engine (inlet manifold was one of them from memory) and comparative power and torque graphs. Unfortunately I later threw it out in one of my cleanouts.
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  #29  
Unread 7th October 2014, 07:48 AM
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Quote:
Originally Posted by guzzla View Post
Thanks Ratbag for the usual detailed information.
You're welcome, mate. I try to comprehend all this stuff, then try to communicate it to others. Sometimes more successfully at both than at other times ... .

Quote:
I do remember that when the SH Forester was released I found a special release brochure from Subaru Australia that explained the many changes in quite a lot of detail, including just what was done to the engine (inlet manifold was one of them from memory) and comparative power and torque graphs. Unfortunately I later threw it out in one of my cleanouts.
A very bad habit that. I never throw anything like that away. Drives my wife nuts ...

Kevin sent me a PDF containing that stuff about the changes between the series II SF and the series I SG (about 30-40 pages). Makes for very interesting reading, and explains many of the details of the design concepts I have tried to analyse in my previous post/s.

Interestingly, the 2.0L turbo SF is only slightly faster over a standing quarter mile than the N/A series II SG. Something like 0.4s, IIRC - not a given at this time of night ... . Not that this is any great indicator of how tractable a car is to drive, just an observation.
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  #30  
Unread 16th January 2015, 04:36 AM
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Oldish thread but im new

I dont think anyone has mentioned that the series 2 sg also has fly by wire throttle body as well as a different shaped manifold if im not mistaken. Also pretty sure it uses a different ecu altogether
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