02 thru 07 Impreza ---What to choose?

[dougkirkbride]

I am reletively New to kit car world, so tons of questions already. Project 818S. i have been researching donar vehicles and am trying to determine what year to focus on and what model, WRX or std. obviously i am going to get the most stock H.P. from an 06 or 07 WRX.......but so expensive. to start this off with one question, is the suspension on a WRX the same as the std 2.5 SOHC impreza? or does the WRX have more sport tuned suspension parts? just wondering where Subaru drew the line on the upgrades: any help is appreciated.

[Xusia]

I'm a cheapskate, so I've researched a lot of options. Like you, I considered a NA build. What I've found is that *IF* you really want more power than the stock NA engine provides, a WRX is the path of least resistance - both in terms of cost and ease of build. I'm not saying don't go NA. What I am saying is don't do that and plan on adding a turbo, or upgrading the engine later. Both of which can be done, but will likely be more cost and headache in the long run. There are plenty of experts on here who can articulate why.

That said, there's nothing wrong an older WRX with the 2.0L engine. As I understand it, with about $1000 worth of bolt on parts, and a custom tune, the 2.0L engine can make near the power of the stock 2.5L engine. I've been told - don't know if it's true, but it does sound reasonable - the the 2.0L is more bullet proof because of the thicker cylinder walls. Lastly, because it's been around longer, there are LOADS of aftermarket parts of the 2.0L engines.

For me, the 2.0L engine has a bit more appeal for it's lower torque compared to the 2.5L. Torque is what breaks the tires loose, and I prefer that not happen too easily. With the low weight of the 818, and no electronic safety nets, going with slightly less torque seems prudent to me. I don't need to have the fastest car to have fun.

[metalmaker12]

Find a clean one for a good price

[RM1SepEx]

The 06 is "best" for single donor... due to the Aluminum LCAs and 2.5 motor.

I found they go for a premium so my 05 rollover w 70K was a good deal. The 2.0 wrx with a header and tune will have very nice power.

The N/A is pricy vs a low mileage wrx donor and the add'l power it brings... but I expect you could do an N?A for zero donor cost pretty easy by parting out what you don't need.

I picked up a set of the AL LCA for 250 and sold my lone undamaged steel one for $53. you give up 30 + HP vs the 2.5 but at quite a savings donor wise. I'm told that I should see 230-240 RWHP with my 2.0 and a tune. After selling off unused parts I'll have only $2000 or so in my donor before my performance upgrades of header/up pipe, lightened flywheel, new clutch, quaife lsd, new hawk pads and drilled/slotted rotors, adjustable rear transverse links. (approx $3000)

I think the key is a low mileage donor, you can avoid having to rebuild everything!

[SixStar]

IMO you want a 02-05 WRX. It's only a 2.0 BUT I make 22/260 to the wheels at a mile high with mine and I'll tell you for sure that it's a ton of fun in a 3100lb car, so it would be a rocket in a 2k car.

FFF is in LOVE with the 06 because of the transmission ratio, 2.5L bottom end and aluminum LCS. BUT what I'm not positive people are realizing is that the wiring on an 06-07 is vastly more complicated for two reasons, they have AVIC and they have imobilizers. For that reason alone I just don't agree with the 06-07 donor. It would be much easier to make a 2.5 hybrid with 2.0 heads, no AVIC and no imobilizer.

[philly15]

get an 03-05 wrx ive hit the 300 whp mark on my last wrx on a well setup vf39 turbo i like the 2.0 motors just because in my opinion drive by cable is better than by wire and i feel overall the 2.0 is much more smooth the only reason im using an 06 wrx is i got it in running condition for $3500 oh and the only reason i say 03-05 is the late model 02's and up had the cryo treated gears in the tranny not like it makes a whole lot of difference but just food for thought

[metalmaker12]

Just to clear it up cause I am a Subie nerd. Its called "AVCS" (active valve control system) and it is not super complicated, plus it adds gobs of torque. The key fab immobiliser will bother some, but it two is no biggy. There is plenty of resources out there to figure it all out. If you had a choice on either donors say 02 or 06, I would get the 02. You can always get lca's and the newer tranny. plus if you want to run a Avcs motor with the 02 harness it is nothing more than repining and adding some wires. A Hybrids can be cool, but if you got a running motor, why touch it. (A nice Hybrid would be a ej257 with jdm version 8 heads, or spec c version 7 heads hint hint). I am running an DBC version 8 ej207 vf37. I agree the ej205 2.0 seems to be slightly more balanced, but the 2.5 has much better low end torque, catch 22. I like the rev of the ej207 and with the right tune is really sings to 8650rpms. The newer the tranny's the stronger they got.

[bromikl]

... it is not super complicated, ... it two is no biggy. ... nothing more than repining and adding some wires.

Easy for you to say! I have never worked on an engine other than a tune-up. Although I once did a (successful) motor swap to an identical engine. (All I had to do was make it look like it did before. No understanding necessary.)

I agree, Subies must be the easiest car to work on, but to the uninitiated they're still a big scary box of stuff we mortals don't understand.

[Mechie3]

There are no big jobs, just lots of little jobs!

Honestly, IMO, Subarus have one (some) of the largest most comprehensive forum(s) in intarweb space. Everything I learned about Subarus came from necessity. Prior to my WRX, I did oil changes and riveted sheet metal to a rusted out fender and painted it black to kinda match the car. I didnt even know how to change brakes.

Then...
bougth a catback, figured out how to change it
clutch went out, followed how to on NASIOC to change that
Bot a new intake manifold, learned how to swap that
Spun a rod bearing, figured out how to swap 1 motor for another
Had a bad motor, followed a how to to learn how to take it apart
Had spare parts, got a FSM and learned how to build a motor

Lots and lots of Subaru resources, and mostly nice people to help. I've seen some forums that are just horrendous and I'm glad Subaru forums weren't like that.

[BrandonDrums]

There are no big jobs, just lots of little jobs!

Honestly, IMO, Subarus have one (some) of the largest most comprehensive forum(s) in intarweb space. Everything I learned about Subarus came from necessity. Prior to my WRX, I did oil changes and riveted sheet metal to a rusted out fender and painted it black to kinda match the car. I didnt even know how to change brakes.

Then...
bougth a catback, figured out how to change it
clutch went out, followed how to on NASIOC to change that
Bot a new intake manifold, learned how to swap that
Spun a rod bearing, figured out how to swap 1 motor for another
Had a bad motor, followed a how to to learn how to take it apart
Had spare parts, got a FSM and learned how to build a motor

Lots and lots of Subaru resources, and mostly nice people to help. I've seen some forums that are just horrendous and I'm glad Subaru forums weren't like that.

Not just your opinion, NASIOC is the 4th largest car forum community on the web. Also one of the oldest and we all know there are several other large subaru communities alongside NASIOC making a solid argument that Subaru could have the most active online community period.

Just like you, before my WRX I only had a little wrenching knowledge. I helped my dad with stuff on our old Hondas here and there. Then I got my WRX and started learning how to mod and maintain. Now I just finished swapping the engine on my own and am about to start rebuilding the old one after a spun rod bearing. Sounds like I'm living your life in a lag.

I think instead of re-wiring an 02 ECU harness, you can simply to a TGV (tumble generator valve) delete, get a JDM Version 7 STI ECU and simply swap 4, add 4 and move 4 wires, a total of 12 wiring changes to the entire harness. That can be done with the harness still in the car.

To the OP: IMO, for the 818 you can't go wrong with an 02-07 wrx donor. Just get a donor with the least abuse for the money and you'll be good. The 2.0L engine probably is a little more ideal for the 818 because of a more linear torque delivery, better engine geometry making it a tad more durable under high revs. However, if you're shooting for just a specific horsepower number, the 2.5L needs less boost to make the same numbers which means less stress on the engine. Weighing that in, any WRX is going to net you a pretty sweet setup so I'd just consider the condition of the car over which model it is.

[SixStar]

Just to clear it up cause I am a Subie nerd. Its called "AVCS" (active valve control system) and it is not super complicated, plus it adds gobs of torque. The key fab immobiliser will bother some, but it two is no biggy. There is plenty of resources out there to figure it all out. If you had a choice on either donors say 02 or 06, I would get the 02. You can always get lca's and the newer tranny. plus if you want to run a Avcs motor with the 02 harness it is nothing more than repining and adding some wires. A Hybrids can be cool, but if you got a running motor, why touch it. (A nice Hybrid would be a ej257 with jdm version 8 heads, or spec c version 7 heads hint hint). I am running an DBC version 8 ej207 vf37. I agree the ej205 2.0 seems to be slightly more balanced, but the 2.5 has much better low end torque, catch 22. I like the rev of the ej207 and with the right tune is really sings to 8650rpms. The newer the tranny's the stronger they got.

We're going to be friends, I can tell.

[PhyrraM]

'02-'05 2.0 WRX. Cheaper, better revs, arguably more "sporty" feeling.

'06-'07 2.5 WRX. More sought after means higher price. More displacement means more potential. Fly by wire throttle means slightly easier build.

[Mechie3]

What do you mean by more sporty? Honest question.

[wleehendrick]

Also not mentioned, the '06-'07 have much better brakes. Sure that's an easy swap, but for someone like me who's doing a straight-forward single donor build utilizing as much as possible from the donor it's a big plus. I'm sure the '02-'05 brakes would suffice for a street driven 818, but they will look a bit anemic behind nice rims and may not be adequate for track use. As Wayne attested to, the '06-'07 11" 4/2 pots are plenty for the 818 on the track, so no need for a pricey Wilwood or Brembo BBK.

Plus, I lucked out on getting a good deal on a fairly low mileage, clean, unmodified '06 WRX... rear-ended CA car, perfect donor! Just a little Simple Green, some routing maintenance items (maybe a little bling) and I'm be good to go.

[PhyrraM]

What do you mean by more sporty? Honest question.

Subjective, but the higher RPM range and the higher and more distinct boost threshhold can be more fun - even if theoretically "slower". You know...When the VTEC kicks in.

[flynntuna]

Also not mentioned, the '06-'07 have much better brakes. Sure that's an easy swap, but for someone like me who's doing a straight-forward single donor build utilizing as much as possible from the donor it's a big plus. I'm sure the '02-'05 brakes would suffice for a street driven 818, but they will look a bit anemic behind nice rims and may not be adequate for track use. As Wayne attested to, the '06-'07 11" 4/2 pots are plenty for the 818 on the track, so no need for a pricey Wilwood or Brembo BBK.

Plus, I lucked out on getting a good deal on a fairly low mileage, clean, unmodified '06 WRX... rear-ended CA car, perfect donor! Just a little Simple Green, some routing maintenance items (maybe a little bling) and I'm be good to go.

Where did you fine your donor?

[wleehendrick]

Where did you fine your donor?

I bought the one Jeff Awender had for sale in San Carlos. He bought it to be an 818 donor, but put that on hold. He may still build an 818, but needed to make space for his current project (Ferrari P4 replica ).

I hauled it down from the Bay Area two weeks ago.

[Tim@ajwperformance]

Funny I just finished this blog up:

http://818donors.com/general/2002-20...2006-2007-wrx/

Kind of a somewhat brief overview, but Im happy to discuss with my friends on TheFactoryFiveForum!

[flynntuna]

congrats, I was looking at that too. The timing was not right, I won't be ready to build for a year or two.

[Nuul]

Subjective, but the higher RPM range and the higher and more distinct boost threshhold can be more fun - even if theoretically "slower". You know...When the VTEC kicks in.

Depending on your tune that can be waaaaaay up in the RPM range for the 2.0L though. Craig was demonstrating this to me last weekend in his winter beater. Anemic before 5K but she likes to go after you hit that threshold.

[wleehendrick]

congrats, I was looking at that too. The timing was not right, I won't be ready to build for a year or two.

Thanks! Since it was a wagon, it doesn't have the Al LCAs, but I'm happy to have a solid platform to work with.

[Mechie3]

Depending on your tune that can be waaaaaay up in the RPM range for the 2.0L though. Craig was demonstrating this to me last weekend in his winter beater. Anemic before 5K but she likes to go after you hit that threshold.

Yup. It's an OTS VF39 tune for an 02WRX. A protune would help, but i'm not about to put money into a car I bought for $3k as a winter car if I don't have to. That threshold is a little lower depending on gear (maybe 4k in second?) but you have to want to accelerate. My 06 would accelerate whether you wanted to or not. It was pretty sweet. :lol:

[BrandonDrums]

A 2.0L shouldn't take all the way to 4k on a VF 39. Tune that sucka! Sounds like whoever set it up just turned down the max wastegate duty cycle across the map to avoid overboost and boost oscillation in high gears. There's far more to tuning boost than that.

I might recommend looking into Hybrid Boost Control to speed up the spool time. It's far easier to implement and tune for since you'll simply use a knob to set the max boost.

Anyway, sorry about the thread de-rail.

[Mechie3]

It's a Cobb OTS tune. 4k is where it hits 18psi (max boost). Not putting any money into it. Bought it in August (sight unseen) for $3k to use as a winter car since my 06 got wrecked. It gets me to/from work in some amount of fun, style, and safety. Overall, I liked my 06 better with the bigger motor/small turbo combination.

[BipDBo]

http://tampa.craigslist.org/pnl/cto/3659676728.html
$4,000
Tarpon springs, FL
2007 Subaru WRX 100,xxx miles
Front-End Damage, Runs & Drives
Stage 2 Mods
Clean Interior
Good Tires

I wish that this was a good time for me to start this project because this looks like a great donor.

[Mechie3]

BS on that running and driving.

Intercooler core is likely full of holes and I can clearly see at least 2 couplers that aren't attached. Even if it was in perfect condition, it would run rough (vacuum leak anyone?). Unplugging the maf, it can run in a default mode, but it'd still run rough and you wouldn't get anywhere.

[BipDBo]

It probably wouldn't go far. You would surely still want to tow it home anyway. That's irrelevant though because it looks to have a lot of valuable parts on it. Depending on the condition of the engine and transaxle, this may be very donor. It's cheap for a 2007. You would definately need to replace the intercooler and radiator at minimum.