[Still Learning] SI Drive, which mode to use??

[Flyboy1218]

Hey guys!

Thanks for those who replied on my previous thread!

About Si Drive, normally I use:

- Intelligent Mode when driving on a 50k road

- Sport Mode when driving on a highway

- Sport # for fun or when someones being smart.

Correct?

Cheers~

[KiwiJoe]

All it does is change the throttle response (and shift points for autos), so use which ever you feel like. It's just a gimmick that has no impact on engine performance. Before I got custom tunes for each of them, I always found Intelligent too slow to react and Sport Sharp too touchy for stop start traffic, so usually used Sport 90% of the time.

Edited June 6, 2015 by KiwiJoe

[Zenki]

SI Drive defaults to Sport when you start the car, so it's probably the normal tune.

Outbacks don't have SI Drive but I suspect they just run in the equivalent of Sport mode all the time.

[Kiwi_Fozze]

[video=youtube_share;QRhKUBX7l8M]

I flip between i and s#... cant say i've ever purpously driven in s.

I is good for warmup, fuel eco etc. S# for funtimes go fast

Edited June 7, 2015 by Joker
[video] tgs & Http - s

[pharnos]

I've just been looking in to this too. Here's the only differences in the ECU relating to Si-Drive (note this doesn't take into account the TCU).

This is the stock ECU for a JDM 2007 Subaru Legacy Si-Cruise (so it has Si-Drive and radar cruise control). Interestingly there's also a few different tables specifically for when in cruise.

Anyway...

http://i.imgur.com/Fuvyt3m.jpg

Edited June 7, 2015 by pharnos

[Guest]

What does it actually change just pedal response? Dbw setup isnt it?

[Andy_Mac]

In stock form it just changes the requested torque/pedal position vs throttle opening % mapping. But limits max throttle opening in I mode so can be pretty dangerous when tou need to accelerate hard but no matter how hard you try the power isn't there.

Individual boost maps for each mode when tuned is probably the coolest part about it.

Edited June 7, 2015 by Andy_Mac

[pharnos]

Found this which helps explain it further...

http://www.romraider.com/forum/viewtopic.php?f=15&t=8652

So there's a separate table for each mode (as in this screenshot http://i.imgur.com/Fuvyt3m.jpg) which sets a "Requested Torque" value based on the "Engine Speed RPM" and the "Accelerator Pedal Angle %"

These Requested Torque values are used in the Target Boost and Wastegate Duty Cycle tables.

The guy in the link at the top has altered the column break-points (whatever you'd call them) for the Target Boost table to coincide with the Si-Drive mode DriveByWire Requested Torque table...

e.g. The maximum Requested Torque in his Intelligent mode table is 350/360:

His Target Boost table's value for a Requested Torque value of 350 is 18psi and 360 is 19.99psi, so when in Intelligent mode his boost is set to 18psi (matches what he says in his post, maybe missed the RT values of 360? Not sure, might be a way of tuning?)

Then he has Sport mode set at a maximum RT of 400 and Sport Sharp set to a maximum 430. The 400 relates to 22psi and the 430 at 25psi in the Target Boost table.

The wastegate duty tables have also been tweaked:

Is that how a tune on a dyno would be done to get the 3 different "max boost" settings. There's only one Target Boost table but depending on the requested torque value, the ecu will pull values from higher up in the table?

Edited June 7, 2015 by Joker

[Kiwi_Fozze]

F**k me, turbo dynamics will be fair s**ting themselves to get the target boost... dont agree with that setup at all imho.... messy. But yeah good description :-)

[pharnos]

He does say he is running a different turbo - "my car has an atp3076 so boosting 25 psi is not a problem"

http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Product_Code=ATP-SUB-002&Category_Code=BCS

[Kiwi_Fozze]

Its more the target boost thats an eye opener... targeting 25 psi at 1000 rpm... thats where the td will be going mental because of the boost error. Target boost map should be scaled to take in to account boost threshold....

[Ramjet]

I run my Legacy in Sport for around town and sport # for cruse control (i-sight) on the Motorway or when i need to get away from the lights a bit quicker. I use to just run in Sport, but found sport # giving me smother uphill acceleration. Economy is about the same. Didn't buy the Legacy turbo for its fuel economy :-)

I love I-sight. It took a while to get use the the car stopping and starting without me doing anything, be hard to live without it now.

[pharnos]

 kwi_fozze said:

Its more the target boost thats an eye opener... targeting 25 psi at 1000 rpm... thats where the td will be going mental because of the boost error. Target boost map should be scaled to take in to account boost threshold....

True, although would it ever target 25psi at 1000rpm? Looking at the Target Boost table it'd only target 25psi at 1000rpm if the requested torque value is 425+

The most aggressive RequestedTorque table (Sport#) has a RequestedTorque value of 425+ at the RPM of 2800+ with an Accelerator Pedal Angle of 80%+

So going by that it'd only attempt to target 25psi if RPM is 2800+ and pedal angle is 80%+?

It does seem a bit basic to me, gotta be more to it to tune the 3 Si-Drive modes better?

[Kiwi_Fozze]

Aaaaahh yeah, i forget theres the requested torque map in the mix too... if it was one of the earlier cable throttle cars the td would be going nuts

[Guest]

Fark me i can see why people go to links...

[Kiwi_Fozze]

Link is no where near as complex.... i like the challenge lol

[Guest]

I like things that make sense. Let the ecu be complicated not the tuning process. Would be good if someone in auck could tune opensource well. Raijin why you so busy.

[Flyboy1218]

Those diagrams are confusing man haha

i guess ill stick to sport mode normally and eco moe when cruising.

Guess shouldnt be thinking about fuel economy if you bought a turbo eh..