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SI drive- Not as advanced as it seems?

PostPosted: Thu Nov 19, 2009 5:56 pm
by Jaz
I was told today that SI drive is nothing more than a reduction in the drive-by-wire settings giving reduced throttle for a given input, and there is in fact only one ECU map, that there is no difference in boost or timing between the different settings from Econo to Sport to sport#.

Has anyone had a look at the maps themselves?

Re: SI drive- Not as advanced as it seems?

PostPosted: Thu Nov 19, 2009 6:33 pm
by overl0ad
there are 4 maps.

base
I
S
S#

each has it's own setting for injector duty, timing, blah blah blah. just that subaru didn't set it up aggressively.

the only thing that i wished it also controlled was the amount of boost.

Re: SI drive- Not as advanced as it seems?

PostPosted: Thu Nov 19, 2009 8:05 pm
by Boxer
overl0ad wrote:there are 4 maps.

base
I
S
S#

each has it's own setting for injector duty, timing, blah blah blah. just that subaru didn't set it up aggressively.

the only thing that i wished it also controlled was the amount of boost.

That's not true,

There are many 'maps' in the ECU but not as you describe.

The SI drive is exactly as above - its nothing more than a throttle vs requested torque relationship. In other words it adjusts the response from the accelerator to the drive by wire throttle.

It is merely because each map references to each other that boost is restricted in I mode. Its done by limiting throttle to say 60% which is the max boost the ecu has set in the map vs throttle

SI drive in a manual is a marketing ploy not much more - do a search its been covered heaps. It can be made more useful in aftermarket tunes by having throttle sensitivty differences but it is still only a dbw map

Re: SI drive- Not as advanced as it seems?

PostPosted: Thu Nov 19, 2009 9:49 pm
by overl0ad
ok.

i'm gonna leave it as that as i've seen the maps.

Re: SI drive- Not as advanced as it seems?

PostPosted: Sat Nov 21, 2009 8:30 am
by Std08GTB
Don't forget that the gearbox mappings change too. It holds the gears longer in s# mode.

Re: SI drive- Not as advanced as it seems?

PostPosted: Sat Nov 21, 2009 10:14 am
by Jaz
Std08GTB wrote:Don't forget that the gearbox mappings change too. It holds the gears longer in s# mode.



Not when you get the 6 speed man. :D

Re: SI drive- Not as advanced as it seems?

PostPosted: Sun Nov 22, 2009 9:47 pm
by parso_rex
As boxer rightly points out, there are three maps not four.
Its not quite as simple as a throttle position change either because boost is referenced off those tables so it does actually affect boost but its hard to explain.

Really you could get a single DBW map setup nicely and not need all three. This is what I\one would do with the pre 07's . In my 08 I pretty much leave it in my modified S mode anyway, its sort of somewhere between the original S and S#. I do use I mode when I'm really tired for some reason

One thing you could do is set it up so You have one normal map then another where the throttle works in reverse in one of the modes and maybe have a second that works in reverse for half the map and then correctly after that, can't do that without SI drive. :good:

Re: SI drive- Not as advanced as it seems?

PostPosted: Mon Nov 23, 2009 9:19 am
by coyote
overl0ad wrote:ok.

i'm gonna leave it as that as i've seen the maps.


Seeing them and understanding them are two different things.

I've seen them too and while I do not profess to be an expert, what you have described is incorrect.

There's actually nowhere near enough space to store what you've described.

Re: SI drive- Not as advanced as it seems?

PostPosted: Tue Nov 24, 2009 11:32 am
by overl0ad
i think it would be funny, if someone managed to get hold of a demo car...

and made ALL the maps identical

and watch the dealer's face when there's no difference.