US Sti Swap?

[one wicked wrx]

well i just got a 2004 sti swap that came with the motor, trans, axles, driveshaft, wire harness, and dccd controls.

will i be able to just use the stock wrx wire harness to run the sti motor and get the kit to run the avcs that kingpin sells?
also will the axles just go into the wrx hubs?
and can i swap intake manifolds cause i have fuel rails on my wrx that i would like to use and dont care much about the red paint on the sti

* Registered users of the site do not see these ads.

[BGPKR]

Wrong Forum

[one wicked wrx]

tha helped

[import111]

Try the conversion section of the forum. You should be able to get some help in there.
Ryan

[Zephyr]

THROTLE BY WIRE!!!!!

You'll need to swap in the entire harness and the pedal box from the STi. You might run into some other issues too.

Z

[Homemade WRX]

Originally Posted by Zephyr250

THROTLE BY WIRE!!!!!

That was my first thought...I guess a lot of guys don't know about that nice little feature...good luck on the swap, I think there is one other brave soul out there braving the swap as well

[dwx]

There are a couple ways to approach this, and nothing is "plug and play".

The steps to using the motor while doing the least amount of work is the following:

Swap the cam position sensor off of your WRX and put it on the US STI head. You'll need to tap the boss that exists for it (the usdm sti does not use this sensor).

Swap the intake manifold, rails, and engine wiring harness off of your WRX onto the STI engine. This gets around the throttle by wire requirements. You will be using the WRX engine harness.

Use your WRX ECU to run the engine, get it retuned.

You are probably wondering, what about the AVCS? My advice, give up on it ever working. You aren't going to be able to make the AVCS system work without using the US STI ECU. In order to use that ECU, you are going to need a bulkhead harness out of a US STI and do a lot of wire splicing. It's as much or more work as putting a WRX motor into a 2.5RS. The US WRX and JDM 2L cars share the same wiring harnesses, engine harnesses, and ECU type. The USDM STI is completely different. So the AVCS kit from Kingpin will not work, it's meant to be used on a 2L JDM motor w/AVCS.

You can run the system with the AVCS disabled and while you won't get the benefits of it, the car will still run normally. Maybe while the engine is out invest in a set of Crower cams, which are $800 or so.

I suppose one way to make the AVCS system work would be to get a set of cams, sensors, JDM ECU, JDM engine harness, and the AVCS "kit". I believe the sensors on the USDM STI are in the same place as on the JDM 2L, but they aren't the same sensors. So you could fit the JDM sensors in there...

I say screw it and just get a set of Crower cams.

The 6MT installation is plug and play for the most part. The DCCD should work fine in manual mode but you are missing some parts to make the auto mode work. The front axles will fit the hubs, as long as it's not an 05 STI. You need a propshaft out of an automatic WRX or JDM 6MT car. The USDM Propshaft won't attach to the WRX rear diff.

[one wicked wrx]

thanks alot for the write up

i knew that it was fly by wire on the sti and thought i could just do like a jdm swap but guess not

and i have the sti rear end so i think it will all drop in

[Zephyr]

You'll need to upgrade your front brakes as well if you put in the STi rear end as the brake bias will be totally off. Things will get ugly really fast if you don't.

Z

[one wicked wrx]

i could also get the brakes but dont know if i just want to use aftermarket kit or use oem

[Zephyr]

If you can get some factory ones for cheap go with them. But you're going to have to go with either the USDM or V7 ones as the other's will not be sufficient.

Z

[one wicked wrx]

iam more worried right now is getting the car to even run! didnt think there was goin to be some many different things that need to be done