Donor Requirements

[memphisraines]

I know it has been said the STI can not be used as a donor, but as someone who would want STI levels of power, can anyone help me understand why. Sorry if this has been posted before, just wondering if the STi trans is too big or if not using the STI as a donor is simple because of suspension points not matching or something. Basically what can or couldn't be used off of an STI.

Thanks in advance

[Mechie3]

Trans is too big. Sti power levels can be had with an 06/07 wrx and the stock turbo.

[memphisraines]

Too big how? STI trans is the better unit and I'd be worried about wrx engine reliability

[Niburu]

its too long

do a little searching, this topic has been beaten to death............. repeatedly

[jham]

The STI transmission is longer and won't fit in the space allocated for the transmission in the rear of the car. I seem to recall some posts about the suspension parts being different too, so if what you're looking for is STI power, you could use an STI engine with the standard 5 speed and suspension bits.

[shim2]

I believe the 818 can use STI suspension parts. They are different but I don't think the mounting points are different.

[Mechie3]

Too big how? STI trans is the better unit and I'd be worried about wrx engine reliability

Trans is stronger yes, but for RWD applications, the wheels will break free much more easily than in AWD mode thus putting less stress on it.

Also, the 2.5L WRX (06/07) and STI motors are almost identical. The shortblocks are the same (minus piston dome shape). Same casting, same crank, same bearings, same rods, etc. The heads are different, but the cams are the same for 06/07. The 06/07 D25 casting heads are actually better than than the STI heads.

I believe the 818 can use STI suspension parts. They are different but I don't think the mounting points are different.

Front knuckles won't work.

do a little searching, this topic has been beaten to death............. repeatedly

We should beat it again......

[Niburu]

do a little searching, this topic has been beaten to death............. repeatedly

We should beat it again......

until it is actually dead?

[NonProfit]

Outbacks qualify as single donors, no?

[Silvertop]

Outbacks qualify as single donors, no?

The smaller Outback Sport does for sure -- It is based on the Impreza chassis. I'm not so sure about the full-sized Outback, which (I think) is based on the Legacy.

My donor is an Outback Sport.

[ScottKoschwitz]

I am now looking for donors and trying to sort out the different models. Like Silvertop, I am leaning towards the 2.5 NA, which would lead me to an Impreza RS and perhaps other models. I remember reading a while back that wagon variants may have a different track than the sedan. Also, I am wondering about gearing. From the specs I've seen., the 5-speed from an RS has a shorter final ratio, which might be better for acceleration in an NA car, but I want to explore the 6-speeds as well.

This leads me to my question: can anyone steer me towards a good resource (online or otherwise) that would provide detailed specs such as front and rear track width, gearing of the different transmissions, and unique specs relevant to an 818 build (aluminum suspension components, etc.)? I've looked through www.RS25.com and a little of NASIOC, but you have to sort through a lot of crap to find any useful information, and I still have found the information I'm looking for.

[wallace18]

search the 818 forum. I remember someone posting all the trans data.

[Mechie3]

I am leaning towards the 2.5 NA, which would lead me to an Impreza RS.

In 06 they renamed it the 2.5i so make sure you include that in your search. There was also a 2.5TS at one point (wagon).

[Evan78]

I am now looking for donors and trying to sort out the different models. Like Silvertop, I am leaning towards the 2.5 NA, which would lead me to an Impreza RS and perhaps other models. I remember reading a while back that wagon variants may have a different track than the sedan. Also, I am wondering about gearing. From the specs I've seen., the 5-speed from an RS has a shorter final ratio, which might be better for acceleration in an NA car, but I want to explore the 6-speeds as well.

This leads me to my question: can anyone steer me towards a good resource (online or otherwise) that would provide detailed specs such as front and rear track width, gearing of the different transmissions, and unique specs relevant to an 818 build (aluminum suspension components, etc.)? I've looked through www.RS25.com and a little of NASIOC, but you have to sort through a lot of crap to find any useful information, and I still have found the information I'm looking for.

Check out cars101.com if you haven't already. Great Subaru resource of OEM data and year by year changes.