SI Drive thoughts

[Boxer]

Guys,

I'm looking for collective feedback on how SI drive really operates. Obviously due to the drive by wire system it would adjust the amount of throttle opening relationship to the accelerator pedal position in each mode.

I am actually wondering if this is all it does? It would be possible to restrict the max power output in 'I' mode by use of part throttle, and 'S' mode gives full power but at a lower ramp angle. So perhaps this is all it really does.

Its a good illusion as you car feel sooo much more powerful in s# when you only use part throttle on the pedal - but floor it and it shows just how much the drive by wire is masking things


Oh and introductions - Sorry - I'm Boxer, picked up the last 07 GT by STI in Black 6MT wagon last week

[EJ25]

welcome mate... congrats on the purchase.. no sure bout SI dirve though.lol

[viriix]

welcome as well.

experiment a bit and see what you think

[I] just sux.. you'd never want to use it. I use it as a valet mode when I get my car valet'd.

[S] is ok, no power restrictions just no as touchy as [S#] but i drive everywhere in [S#] nowadays, no difference in fuel economy imo.

If you drive hard in [S] or [S#] it's going to drink a bit.

[adam]

my wife uses more pertol (pertol, what the hell is pertol?) in [s] accelerating at normal rates than i do in[s#] kicking it in the guts at every given oppourtunity.... go figure. i think that the [i] mode is as much about driving style as it is power reduction imo.

[viriix]

Hehe.. but [I] mode is just a pig, it's great for sunday driving if you want to slowly accelerate and just cruise around.. don't even try to think about overtaking.. even if you downshift.. a few times.. lol

Probably good for learning how to drive ie. L platers... where you don't want such power/throttle accessible in the car.. hence it's great for Valet mode.

Because it's guaranteed that any car you sit in, you have to re-adjust to the throttle, braking, and even clutch etc the actualy physics and dimensions too.. mirrors.. whatever.. lol

So.. with [I] it minimises it to be simple to drive :]

[coyote]

Hello Goxer!

[Boxer]

Hello Goxer!

Greetings SUBOOOOOOO

[Roddez]

I was talking to the service rep at Bankstown Subaru about he SI drive system.

He suggested that it changed the engine management mapping in a number of areas:

Turbo waste Gate which = boost pressure
Spark timing
Throttle response (Amount the butterfly valve opens and how far)
Valve timing - This one I am questionable about because I didn't think the MY07 GT-B had variable valve timing.

Given the amount of technology in cars these days, it is quite possible to regulate all these things to change the output of cars. Heck, they have been doing it in the aviation industry for years. The same PT-6 engine can produce as little as 200SHP and over 1000SHP just by tweaking the engine management systems.

I tend to use either I or S#. I use I when I am in a bad mood, or when the car is cold. I will also use it when just tooling about the place. Then when I want something to happen, just press that S# button on the steering wheel and smile.[/list]

[viriix]

lol tooling around..

i do that in s#.. tap the throttle to stop the person getting infront.. tap the brake to make them stop tailgating.. :]

you could say i'm just a tool in general :p im sure jimmy would agree..

[EJ25]

lol tooling around..

i do that in s#.. tap the throttle to stop the person getting infront.. tap the brake to make them stop tailgating.. :]

you could say i'm just a tool in general :p im sure jimmy would agree..

lol.. i was going to agree b4 u mentioned me..

[viriix]

xD

dude.. when the hell did your posts hit 300+? :p

jeez..

anyways..

back to topic.. im surprised that i get around in [S] sometimes and look down and go oh.. [S] no wonder it felt a bit less punchy :p

[Mo_GT]

Its a good illusion as you car feel sooo much more powerful in s# when you only use part throttle on the pedal - but floor it and it shows just how much the drive by wire is masking things

Thats correct. But in addition, even on S#, you don't get full throttle.

[MY07GT]

I was talking to the service rep at Bankstown Subaru about he SI drive system.

He suggested that it changed the engine management mapping in a number of areas:

Turbo waste Gate which = boost pressure
Spark timing
Throttle response (Amount the butterfly valve opens and how far)
Valve timing - This one I am questionable about because I didn't think the MY07 GT-B had variable valve timing.

I spoke to Dave who is a mechanic at Subaru who told us it has nothing to do wif boost pressure.

Phil.

[Mo_GT]

I was talking to the service rep at Bankstown Subaru about he SI drive system.

He suggested that it changed the engine management mapping in a number of areas:

Turbo waste Gate which = boost pressure
Spark timing
Throttle response (Amount the butterfly valve opens and how far)
Valve timing - This one I am questionable about because I didn't think the MY07 GT-B had variable valve timing.

I spoke to Dave who is a mechanic at Subaru who told us it has nothing to do wif boost pressure.

Phil.

Hmmm...in a broader sense, Roddez might be right Phil. While it doesn't have anything to do with wastegate control, the SI drive does alter boost - easy way stick a boost gauge and see what max boost you hit on a certain gear in I, S and S#.

[Mo_GT]

Oh and Roddez, the 07 GT Spec B does have AVCS.