"The Swap"

[Reason]

Few of you know that I was toying with the idea of a WRX swap. Well after talking with Gator GT and James at East Coast Swappers for the past 2 month I will start getting parts. More so the parts that can be change with and motor I choose.

I'm writing this post to keep for my personal record and to share with everyone here. Opinions and suggestions are always appreciated. I will start with a list of parts I need and have. Then will mark progression as I go.

What I need before the swap

[ ]WRX motor
[X]Perrin pulley
[X]STi engine mounts
[X]STi pitch stop
[X]Crucial 160 degree T-stat

[ ]RS tranny
[ ]Kartboy short shifter
[X]STi tranny mount
[ ]Exedy clutch kit

What I want after it is done

[ ]Turbosmart BOV
[ ]STi top mount? Perrin top mount? turbo xs top mount?
[ ]Cobb or SPT intake

I want the largest top mount that will fit under my hood. I also not sure what Header I should go with :-?

[Wiscon_Mark]

RS tranny? Go with an 05+ WRX tranny.

The advantage: cryo treated gears. The RS tranny won't hold up long.

I voted Perrin TMIC, because some STi owners go with it as an upgrade. However, any will suit your needs, as it doesn't look like you're going crazy with the boost with this setup.

[Reason]

Well I was going with a WRX tranny but the RS has shorter gears. James at ECS has a WRX with a RS tranny. I'm talking to a few guys on WRX forums to see if anyone else runs the same set up.

As for boost I don't plan on adding more till sometime next summer.

[SlowLeg]

I've read that too about the RS tranny being faster with the WRX engine. Keep us updated on your progress. I want to learn as much as i can about doing this swap because a couple of years down the road i want to do this. You should keep a journal and picture record of the swap, im sure it would be a great additional resource in our forum.

[blackgtbeauty]

yeah 04 and up they used RA gears in the trannies (hardened and wider).

i thought that the RS and our stock 5 spds were the same?

(yeah post #100)

[Reason]

yeah 04 and up they used RA gears in the trannies (hardened and wider).

i thought that the RS and our stock 5 spds were the same?

(yeah post #100)

Yes but I have a 4EAT :roll:

I just got back from NH to meet Gator GT (cool guy by the way) and picked up some parts for the swap. This dude knows his stuff and helped me alot over the years.

Before I get more parts for the swap I'm doing all the tie rods, ball joints and wheel bearings. Parts under $200 from Subaru, I might have ECS do it while my car is apart to save myself money.

[Huffer]

You should just use an STi engine if you're going to all this trouble? I dunno.

The WRX engine is pretty good with a good tune (Cobb AP Street Tuner). Fella round my area runs a 20g w/ modified injectors, fuel pump and an APS TMIC, making 400whp on ras gas with a Cobb AP. 2004 WRX.

I would think, you may have some clearance issues with the bigger TMICs.

[Reason]

The STi swap will double the cost of the WRX swap. Also I'm not looking to get HUGE numbers, thats a whole new project when I get an H6 :twisted:

[Wiscon_Mark]

The STi swap will double the cost of the WRX swap. Also I'm not looking to get HUGE numbers, thats a whole new project when I get an H6 :twisted:

That's my eventual route :smile: (H6, that is)

[scottzg]

the rs tranny is not compatible with the wrx accessories, one is pull type, one is push type. Heck i think wrx's have hydraulic clutches. A good tune will give you a lot more power than a different topmount and an intake and headers. Ya need a new pedalbox. I remember there was some reason not to run iridium on a turbo motor or something, but i totally forgot the details. RS tranny has a lower first and a taller 5th than the L trans. I'm not sure that's a benefit in a turbo car.

Have fun!

[Reason]

the rs tranny is not compatible with the wrx accessories, one is pull type, one is push type. Heck i think wrx's have hydraulic clutches. A good tune will give you a lot more power than a different topmount and an intake and headers. Ya need a new pedalbox. I remember there was some reason not to run iridium on a turbo motor or something, but i totally forgot the details. RS tranny has a lower first and a taller 5th than the L trans. I'm not sure that's a benefit in a turbo car.

Have fun!

James at ECS has the same setup in his car. I have confidence in them that it will all come together. Once the swap is done it will be tuned by the same place where I did my dyno runs. It will be quick, that's what I'm looking for.

[Perdue]

I voted for the STi TMIC...I like bein able to look through a hood scoop and see the STi peeking out under there.

As far as the RS tranny, it's actually not bad. The case on the pre-wrx 5-speeds are actually stiffer. It seems a lot of the problem in using the stock 5 speed that comes in the WRX is that the case flexes under stress and misaligns stuff...that's bad. The RS tranny can't be beat for moderate power though (wouldn't stick 500hp to it or anything). The 4.11 gear ratio isn't bad either. I know there are a lot of shops doing swaps into RS's that recommend keeping the RS tranny.

I'm not so keen on cyro treated gears. IIRC, the RA gearsets are cyro treated and I've read on NASIOC of people blowing them out just as easy as the stock 5 speed, and having paid upwards of 2k for the gearset. Not cool. Best route for big power would be a dogbox IMO.

[Wiscon_Mark]

haha, you can ask BAC5.2 about his dogbox :twisted:

[Sarra]

RS and WRX... Well, WRX has a higher redline, so they used longer gears to bring the RS and WRX closer to shift points as speed goes.

I'd vote for STi RA gears in a WRX tranny casing, though if you can get the RS gears treated, then you should be okay to go anyway.

I know I'd sure as hell never put more than stock power through my legacy's stock gearbox, it's having trouble holding up to stock power!

[Reason]

This is just a simple swap so I don't get even more bored with my car. By no means am I building a monster. I talked to a few people that run this set up. One guy had 2 WRX motors and a STi on the same RS tranny.

[sheepdog]

If you put RA gears in anything I have an empty 2.5rs tranny case.

As for a wrx engine, James should have a hookup for that, tell him to give you Frank's number.

I'll also check on getting you a deal on one of the old Speed Factor topmounts, we might still have a few laying around, and are better or equal to any of those topmounts you listed.

[blackgtbeauty]

what about finding a 05+ LGT tranny? i mean by the time you get the ra gearset and the donor tranny... $$$

[Reason]

All the parts I need are at my finger tips. All I need is more money. Does anyone want to donate to my swap?

[Reason]

Well my engine is acting up so I have to push the date closer to get this done :grin: Still don't have a date yet but will know when I get the rest of the parts for the tranny and exhaust.

[badbasser98]

Does anyone want to donate to my swap?
sure at 20% interest :twisted:

[Huffer]

What condition is your stock exhaust in? I'd be interested in that!

[Reason]

What condition is your stock exhaust in? I'd be interested in that!

The mid pipe and muffler is gone. Not sure how the cat and header is. ECS keeps everything from my stock setup to keep cost down.

[Huffer]

Damnation. See if you can get it back, I'd be interested in it.

[Reason]

Damnation. See if you can get it back, I'd be interested in it.

I threw the old exhaust away. I had a chance to get rid of it so I did. I might sell my SPT axle-back. I bought Gator GT's Borla axle back which I love. The SPT is nice too but the piping is stock size.

[Huffer]

I might sell my SPT axle-back. I bought Gator GT's Borla axle back which I love. The SPT is nice too but the piping is stock size.

Fair enough - let me know about the SPT if you decide to sell. :)

[xcntrk75]

I have an 05’ WRX 5MT forsale if you’re interested. Comes stock from Subaru with the stronger RA-width 1-5 gears, dual cone syncro’s, and more favorable clutch setup. It’s the wrx 3.9 FD with the 1.1:1 center, meaning you’d need a WRX lsd rear diff. Let me know if you’re interested.

Also, is ECS supplying the harness, ecu, fp controller, and all necessary components to address the wiring? Also, you’ll need a harness which includes the tranny cords intact since you’re moving from an AT platform. Also don’t forget about the pedal box, master/slave cyclinders, neutral safety switch, cruise switch, and starter interlock relay (MT). Lastly, if ECS has any problems getting your ABS to work with the tranny swap, tell them to keep the TCU. Even though it’s not managing anything while plugged in, it seems to be the only way to keep the ABS happy and functioning. Took me over a year to figure that one out :lol:

[Reason]

Besides aftermarket parts, ECS will supply me everything I need. I don't use my ABS anymore, so I'll make sure it won't work when they are done.

[BAC5.2]

It's all about what you want to get out of the swap.

Ideally, Anthony has the best setup I can think of. He finally has a tranny, and the car is beautifully put together.

We have a LOT of experience with transmission setups, gear ratios, and all kinds of transmission info.

One thing I can tell you is the myth of RA gears. They aren't hardened, and they aren't anything really special. What you ARE getting is an OEM gearset that was never designed to handle more than 276bhp.

The 05 OE WRX gears are not cryo-treated or anything special. They are no different than the 03.5+ gears (being 1mm wider than the 02 gears).

Here's the real deal from everything I've seen. For a stock WRX turbo, the change to a shorter gear ratio isn't going to hurt very much. But the second (and I mean the second) you use a larger turbo, you will notice an increase in turbo lag from the shorter gear ratios. You'll also notice that you might not make full boost. You will ALSO be shifting like a friggin maniac going down the track because top-speed in each gear is significantly reduced. You'll hear a LOT of people disagree with me, but I've got a TON of customers who agree. In fact, I've flipped people from RA gears onto PPG setups, and they immediately see the light. I have never had any customers regret a PPG setup.

I've even tested final drive changes, gear ratio changes, and trans type changes in my own car. When I was RWD, my final drive was 4.29:1. It sucked. Turbo lag like crazy (though it was kind cool to break loose at the top of 2nd). Then I went back to AWD, and a 3.90 final drive. PPG Straight Cut Syncro box. Same gear ratios as when I was RWD. Turbo lag dropped back, and the car was noticeably faster. Then I went to a dogbox, still AWD and 3.90FD. There is simply no comparison for a dogbox. It's the ultimate driving tool if you can man up and deal with it.

I have lots of customer testimonials about the benefits of longer gear ratios too. Specifically 2 customers with nearly identical setups. They each were playing with 400+whp STi's (other customers of ours), and each of them only made 320ish whp. Both hit it from a roll, and in one case was dead even with the STi (315whp wrx, 430whp sti). The other spanked him (320whp wrx, 400whp sti). It was all gear ratios that won the races. While the STi's were shifting into 6th gear, the WRX's with PPG transmissions were just reaching the top of 4th gear.

Transmission is all up to you. If you feel my advice is worth anything, I'd suggest a stock WRX transmission for now, and an upgrade to a PPG syncro set when you want more power.

This is just an FYI post. I've learned more about transmissions, and drivetrains in general than I can remember all at once. If you have a question, I've probably got an answer.

Phil