[griffmac]

Anyone seen any Dyno numbers on the 2.5L? Should we expect any increase in low-end power over the WRX. More displacement but a bigger turbo so will we see still significant turbo lag. I know it has 300lb-ft at 4000rpm, any know how much at 2500 or 3000.

A lot of the STi (2.0) vs Evo VII comparisons in England mention the wider powerband of the Evo. I notice the US spec Evo produces 270lb-ft at 3000rpm. I'm not trying to compare the US Evo to the STi because that thing is a pig at 3300lbs.

 

[CloNeGTS]

I don't think anyone has received a US Spec STi to drive...test...anything yet.

 

[miked801]

when they do they'll have to find a 4-wheel chassis dyno, right? or does the wrx have an awd fuse you can pull or something like the skyline?

 

[jbhebert]

The AWD system on the STi is primarily mechanical. No matter what, some power is always going to the front and rear wheels. The Skyline uses clutches and servos to distribute power. When the infamous fuse is pulled, it kills power to the front drive system and makes it RWD only. SO, short answer, yes, they'll need to find an AWD dyno or temporarily convert the car to FWD by removing the rear driveshaft and plugging the rear of the tranny.

 

[91TB78]

won't plugging the rear drive-shaft be bad for the clutch?

 

[murley]

Hey there guys! Your Subaru Gu-Ru salesman is here to help dispell your quarell! EVERY current model year Subie does in fact have a 2WD fuse in the engine compartment fuse box. Simply plug ANY spare fuse into the receptor and VOILA--- 2WD! Simple as that. I do suppose that the 04MY's will also have this feature for towing protection!


Jason Murley
Lujack Subaru
Iowa/Illinois
800-373-1160 X-236

 

[miked801]

now that you mention it i seem to rmember something about that in the user's manual for my 1999 outback wagon...

 

[darwood]

Simply plug ANY spare fuse into the receptor and VOILA--- 2WD! Simple as that. \

This might work for the automatics since I don't know anything about their awd system, but the manual transmission WRX's have viscous coupling center differentials. Viscous couplings are always on since it's a mechanical coupling that is kinda like a torque converter (but not quite). You have to have a flat bed to tow a WRX.

 

[CloNeGTS]

Yeah...I was gunna say...how do you shut down the center diff? I can't imagine there is an electronic control in the tranny to 'switch off' sending power out the back.

 

[darwood]

Yeah, I can't think of how you would "turn off" a center diff other than using some sort of clutch, which seems like too much effort just for towing. The automatic WRX's have the adaptive awd system which I don't know enough about. I know normal viscous couplings can't be turned off.

As far as the DCCD goes, I don't know enough about this system to say wether or not you can uncouple it. I'm going to say no, but really don't know for sure.

 

[91TB78]

Murley might be right on a WRX, but the STi has the center diff...cannot do that.

 

[darwood]

Here is what I was able to find off the Subaru website:

Manual transmission models have a viscous-coupling locking center differential. Automatic transmission models have Variable Torque Distribution (VTD). VTD utilizes a planetary center differential in conjunction with an electronically managed continuously variable transfer clutch.

I think this answers some questions. It looks like the manual transmission WRX's have mechanical viscous-coupling center differentials so disengaging this with a fuse seems very unlikely. The VTD in the automatics mentions a continuously variable clutch which goes along with the fuse disengagement requiring a clutch of some sort. So it appears it all depends on the transmission.

So yay, everyone is right

Now about the DCCD system I don't know. 91TB78 I'll take your word on it. :wink:

 

[jbhebert]

won't plugging the rear drive-shaft be bad for the clutch?

What I meant to say is plugging the whole in the back of the transmission where the rear driveshaft was so the fluid didn't leak out.

 

[91TB78]

gotcha!

 

[murley]

Hey there guys! I just got done looking under the hood of a new 2003 5spd WRX and it also has the FWD fuse. Although I did however read the owners manual and it states that the FWD fuse will only activate the FWD on an automatic tranny that doesn't include the turbo. Sorry for not doing my homework in advance... (