Jeff - 2008 Subaru Liberty 2.5i NA 5MT ADM - Tuning

2008+ Subaru Legacy/Outback
west_minist
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Jeff - 2008 Subaru Liberty 2.5i NA 5MT ADM - Tuning

Post by west_minist »

Info
Owner: Jeff - Australia
Rom: E2TB102M
Tyres: 215/45-17
Car Weight: 1365kg
Driver Weight: 105kg
Total Weight: 1470kg

Mods
NA

Transmission
1st: 3.454
2nd: 2.062
3rd: 1.448
4th: 1.088
5th: 0.780
Final Gear: 3.9

BP Ultimate 98 octane

All dyno'es are based on RPM.
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Stock Performance

Post by west_minist »

Stock Criticals.png
Stock Criticals.png (181.23 KiB) Viewed 16542 times
Stock 3rd Gear Dyno-rpm IAT=19C.png
Stock 3rd Gear Dyno-rpm IAT=19C.png (18 KiB) Viewed 16512 times
Stock times.png
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Customer Feedback on First Rom

Post by west_minist »

The car is definitely pulling better giving me a lack of "lag" on the throttle, being more responsive in general, and there it feels as though there is virtually no effort in climbing hills. I had to remind myself about the difference by quickly flashing back the original ROM to compare.

While the car is overall much more driveable with much smoother gear changes, I'm having a little trouble doing slow stop-start driving in traffic in 1st gear without using copious amounts of clutch to compensate for me accidentally over-revving the car as I'm used to putting more throttle in with the original ROM. Over the day of testing, however, I managed to handle this a lot better so I know there will be a period of personal adjustment as we go through each version as I found myself almost stalling the car late in the day when I went back to the original ROM to compare against.
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v0a

Post by west_minist »

New Dyno'es being ran.
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Re: Jeff - 2008 Subaru Liberty 2.5i NA 5MT ADM - Tuning

Post by west_minist »

http://forum.liberty.asn.au/viewtopic.p ... 88#p182359
HyRax wrote:The importance of consistency!

As you can see, all my runs are all over the shop. I've been doing my runs on a highway which means a rolling start and never an exact starting point due to making sure no other traffic is around me.

You really do need to find a quiet, flat static road that you can start from the exact same point every time so that the road incline and direction never changes halfway through your run.

Anyway, while I continue to search for that quiet, safe road that doesn't require me to travel an hour to get out to, Edward has done well to make do with what I've given him and I've gone through three ROM's already. Edward is so good, that even before I had a chance to apply v0 to my car, he'd already given me v0a! I am now up to v1 and continuing testing.

With the v0a ROM already, I'm finding the car has much greater driveability - the car feels "lighter" to drive. When comparing against the original ROM, the throttle felt extremely laggy on the original and light and feathery on the v0a ROM. It is just a starting point, but it's very easy to over-rev the engine in start-stop traffic and I've had to adjust my foot application as a result. Edward's v1 ROM seems to have addressed this by reducing the "friskiness" of the throttle from standstill a bit, but I'll probably get Edward to tweak it up a little more again to make it feel a little more in line with the higher revs as I'm now getting used to it and prefer it now.

Where the car could bog down easily from standstill if you didn't apply enough throttle before releasing the clutch, the car now easily and effortlessly moves away from standstill. Where the was a small lurch in gear changes, the majority of up changes under v0a are smooth as silk under normal or hard acceleration.

Driving up a hill is easier as well - where you might have applied a certain percentage of throttle to climb before, it feels as though you only have to apply half that throttle and you are achieving the same power, if not more power, to climb instead. The engine does not appear to be revving any harder for the task.

From a noise perspective, the engine sounds gruntier and I even flashed back to the stock ROM to compare - you can instantly feel the large differences already despite being so early in the tune. Kudos to Edward for that.

The v1 ROM is designed to introduce tweaks to power/torque into the tuning regime and I'll be testing that properly tonight. So far the drive this morning on v1 felt really good in back streets, but due to overall traffic volume I haven't really been able to put my foot down. The car should feel faster than before on this ROM.

Edward has proven to be great to work with - he's always available on IM or email and in fact he's been badgering me for new logs a lot - I almost feel I'm letting him down with not being able to get the data soon enough! ;) I entered into tuning with XRT with the aim of increasing driveability of the car and increase fuel efficiency, but I am confident that I will see some power/torque bonuses by the end of it as well. I don't expect improvement percentages to be as great as you would have on a 3.0 or GT, but I still think this is money very well spent. I'm learning a lot about the fine art of tuning, and Edward is more than happy to answer any questions I have, and encourages me to ask them as well.
HyRax wrote:v1 ROM update

Tonight I did some formal lead-foot tests of the v1 ROM.

Hoooo-ly crap...! The car is on fire! Who'd have thought there was so much untapped power in the 2.5i?? With NO MODS???

The car actively pulls and powers on and on and on, all the way to redline with only a slight softening of puff as you pass 5,000rpm. Under 4,000rpm, the car was still perky from the v0a ROM, but v1 really took this to the next level above 4000rpm with the tweaks in timing and fuel.

I finally found myself a good, safe road to do pulls on that wasn't a highway, so I re-did my stock and v0a pulls to maintain consistency between each ROM release. Again, when I went back to the stock ROM after being tantalised with v1, it felt downright horrible. It was so laggy I felt as though I was driving an untuned WRX with a monster aftermarket turbo. I couldn't believe just how much extra throttle I was putting in to compensate for the lag under the stock ROM - all without realising!

While the car felt awesome, there was some pinging which was the result of Edward exploring the upper limits of changes. The next ROM, v2, will go back to the more conservative v0a timing and introduce some changes to the bottom end as Edward is not happy with what he saw there in my v1 pulls tonight from a fuel perspective.

And true to form, Edward prepped v2 very quickly - ready to rock in my InBox within minutes of posting him the new logs! Will flash and run new logs tomorrow.
HyRax

Re: Jeff - 2008 Subaru Liberty 2.5i NA 5MT ADM - Tuning

Post by HyRax »

The v1 ROM was amazing fun, Edward. Shame about my low-quality fuel causing some pinging, but once I change stations hopefully this problem will work itself out. Thanks to your work, I'd have never known that my local BP was supplying low-quality fuel. Once I test and confirm another BP station is supplying better fuel, I'll write into BP to complain about the first station.

Results should now be more consistent with a new set road to do my dynos on too. Re-did all my dynos on stock, v0a and v1 ROMs for Edward last night. Edward tells me that v2 will return to more conservative timing for now to start examining other areas for improvement.

I'm really hoping we can return to maintaining those levels of power by the end of all the tuning, though, because that was fun! :)

It just goes to show that Edward can perform magic even with a lowly 2.5i. He's been worth every dollar spent!
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v1 Stats

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v1_v0a_stock 3rd Gear Dynoes-rpm.png
v1_v0a_stock 3rd Gear Dynoes-rpm.png (27.63 KiB) Viewed 16518 times
v1 Dyno Runs IAT=18.5C - Pulls1_2_4.png
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v3 Stats

Post by west_minist »

v3 3rd Gear Dyno-rpm IAT=19-20.5C.png
v3 3rd Gear Dyno-rpm IAT=19-20.5C.png (21.09 KiB) Viewed 16512 times
v3 times.png
v3 times.png (1.91 KiB) Viewed 16512 times
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Customer Feedback on v2

Post by west_minist »

http://forum.liberty.asn.au/viewtopic.p ... 24#p182673
HyRax wrote:v2 ROM update

This release saw a return to v0a timing but with some bottom end changes that Edward made, so I wasn't expecting the car to be as exciting as v1 was, but I was wrong. The car, while not quite as "brutal" feeling as v1 was, was still a lot of fun and it still felt like an "angry" car. I found second gear to be very deep and powerful and gear changes were still fairly smooth except for 1st to 2nd in hard driving acceleration only which seemed to lurch a little, but not by much. Normal driving acceleration in all gears felt smooth, however.

I found third gear to be very linear in its pull again like v1, and 1st gear also pulled off the line very nicely.

I found flat-footing in 1st gear to exhibit a small stop-start jump, but that was probably me applying too much throttle too early and not letting the clutch slip enough before the car could get physically moving properly.

Interestingly I found reverse gear going up into someone's driveway to do a three-point turn to be very nice! You never think about reverse until you are doing it up a hill, and I found it effortless to get up this incline to turn myself around.

One thing I found with second gear while doing some, er... evaluative hooning, was that when I deliberately changed at 5,000rpm, the car consistently revved up about another 500rpm which felt as though the car was still accelerating by itself - I could see this was the normal auto-rev that occurs in normal gear changes, but it gave me a momentary spook as I thought the car had decided to go off and do its own thing with a stuck throttle.

Overall am I finding the car to be very responsive with an apparent increase in torque in second gear. Acceleration is linear, particularly in third, and when the car is on song above 3,000rpm, that is when it feels the most meaty, so I found myself deliberately changing gears quite high to keep the next gear above 3,000.

Another interesting thing I observed was my fuel economy meter. Under the stock ROM, if I hooned around, the meter's estimated distance to empty very
quickly diminished - we're talking fill up with an estimated distance-to-empty of about 600kms very quickly dropping to 300kms within a few hours of lead-foot action. This time around, despite this current tank being hooned on a lot more than driven normally by a factor of about 3:1, the estimated distance-to-empty is remaining quite high for a change - currently reading 400kms with 130kms burned off on this tank already. Since I am deliberately trying to burn off this tank in a bid to refill it with quality BP Ultimate from another servo, it will be interesting to see what my final kilometre tally will be for this tank.

The idle rpm has been raised from the factory 750rpm up to 800rpm, and this has surprisingly helped moving from standstill more effectively than I imagined - getting off the line, especially if it's a deliberate slow start such as crawling in stop-start traffic, is easier than before.

The v3 ROM which Edward has posted me today will be a longer-term test. I'll be running it for a handful of days to see what learning the ECU will do in that time. As a challenge, Edward isn't telling me what has changed until I've run v3 for awhile, so I'll have to give him a seat-of-the-pants review over the next 24-96 hours! :D

I continue to be amazed at the noticeable differences between each ROM release. Edward truly is a master of his art. Careful and methodical, he really gets results!

Looking forward to flashing v3 tonight!
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Customer Feedback on v3

Post by west_minist »

http://forum.liberty.asn.au/viewtopic.p ... 15#p182786
HyRax wrote:v3 ROM update

This was a very nice update. It was up to me to determine what Edward had changed in this ROM and one thing stuck out very quickly - the bottom-end is much stronger now. Fuel comes on very early and I attain quite high acceleration on very little throttle.

As a typical example, let's say you were high-geared and low rpm, eg: 4th gear at 2000rpm. On the stock ROM if you put your foot down flat to the floor, the tach very slowly starts to raise but the speedo doesn't really budge for another 3-5 seconds. Now I can put in less than 50% throttle and the car will pick up 5kph in about 2.5 seconds in 4th gear from 2000rpm. Useful in day to day traffic? Of course not, but it's a good indicator of how much more responsive the engine is at the bottom end.

In sensible gearing, the car picks up very quickly now. It's easy to hoon around and get to 100kph without even getting close to getting flat to the floor. of course power-runs will still require you to go flat-foot, but the majority of the power is delivered at the top of the pedal now, and I like it. Flat-footing it barely adds anything to the acceleration force you've already got.

1st is very strong now making it a doddle to get off the line as before, 2nd gear feels a bit stronger than it did in v2 and remains my favourite gear, but now that third is a lot stronger than before, I can easily take more corners in third without feeling like the car is about to lag and require a drop to second. The new bottom end allows the car to build up from low rpm quicker than before and get back into the meaty sweetspot of rpm nirvana. In a typical long left sweeper, the car just felt magical powering through it in third.

Where power used to come on at about 3,000rpm, getting meaty at 3,500-4,000rpm, the car now starts to come onto power at 2,600-2,700rpm and is in the sweetspot from 3,000rpm. The car powers onto 5,000rpm where it starts to lighten up a bit but it still gets to the redline pretty quickly.

One of the little differences I found in this release was the fact that I could actually feel myself being pushed back into the seat a bit for a change. Before you just more or less floated in your seat with a depressive force here and there, but now you can actively feel yourself being pushed back into the seat instead of it just being a comfortable, but laggy affair under the stock ROM.

In casual driving, 1st to 2nd gear changes were still a touch lurchy, but all other gears were fine. In hard accleration, all gears were silky smooth. In slow stop-start traffic, I found 1st gear still touchy, but more controllable and I did not need to rely on extra clutch action to control the extra throttle like before. As a side note here, when the car is cold, the car is lurchy in all gears, but once the car has warmed up, things are fine after that. I usually drive no harder than 3,000rpm for the first 10 minutes of driving to warm the car up anyway.

In high revs, gearing down actually felt and sounded more sympathetic to the car - it doesn't sound like it's simply revving its guts out anymore - it sounds much "cleaner" now, so now coming down from 3rd to 2nd is easier, but as I said before now I don't even need to take 2nd - third will climb back sufficiently now. Even letting the revs get down low enough that if you did take second, the traditional bogging down is near-eliminated because the car can quickly get itself back into power territory.

On the economy side, I've now racked up just over 200kms on this tank and the estimated distance-to-empty still only says 380kms! That's great considering how much hard driving I've done on this tank in a short time.

As you can see from the logs in Edward's post above me, compared to stock, he has manage to extract an extra 10kw of power and 15nm of torque overall. Remember that my car has had zero modifications of any sort in the engine department. It may not sound like much, but a 2.5 litre N/A engine, I think that's pretty good.

I was supposed to run the v3 ROM for a few days to see how the learning component of the car goes, but Edward has already sent me v4 already, so I've got that on the car and again will do more testing tonight, and presumably over the next couple of days. The v4 ROM now features some ignition changes so we'll see what difference that makes.
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