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98 2.5RS ~ EJ257D Hybrid
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IMPORTANT, IF YOU DO NOT HAVE THE ABILITY OR UNDERSTANDING TO REMOVE AN ENGINE AND A TRANSMISSION, YOU WILL NOT BE HELPED BY THIS INFORMATION, THIS INFORMATION REGARDS PROBLEMS THAT WILL BE ENCOUNTERED DURING AN AUTO TO MANUAL SWAP

THE FOLLOWING WILL/MAY BE LOST DURRING A CONVERSION

CRUISE CONTROL
ABS (believed to be solved by retaining the TCU and using a resistor to give the TCU the illusion of being in neutral, this doesnt solve cruise control) read more here Legacy Central -- Transmission Conversion and here '98 RS 4EAT to 2000 RS 5MT w/ LSD - NASIOC

*CREDIT!* I recieved a large amount of technical and mechanical help From http://www.rs25.com/forums/members/12555-sleepysubie.htmlSleepySubie on my project, All credit goes to him, I provided the garage and the budget for this learning experience. *CREDIT!*


This covers an RS Transmission swap, more specifically a 98 RS Auto to a 2000 RS Manual,

Step 1: Parts collection (the following is specific to my situation, specifics may vary without notice)

Manual Transmission (including mounts)
Matching Shifter Linkage (includes bushings/nuts bolts ect.)
Matching Shifter (Ensure that you have ALL bushings and screws)
Matching Flywheel and Clutch/Pressure Plate
Matching Clutch (master and slave) and Pedals *NEED CONFIRMATION, on brake pedal engage switch*
Matching Manual Starter
Manual Drive shaft
Manual Rear differential (be sure to match gear ratios, consider this a great time to upgrade to LSD)
Manual ECU Not Required but fuel maps are different between the two. (Same year/trim as your vehicle RS gets RS, L gets L, WRX gets WRX)
your model/trim shifter trim and shift knob (Auto shifter trim offers enough clearance for proper shifting with a short shifter without modification)

We used the 98 RS Automatic CV Axels for both front and rear, if you check with any retailer of rebuilt or oem replacement parts they tend to use the same part number for both auto and manual variants, which could show either that these parts are the same or that these retailers dont care, I'm going with the first as the 2000 rs axels appeared identical to the 98's (in the rear, the fronts had the ABS ring on the axel vs on the hub no spline additions or extras aside from that) they will how ever charge extra for one or the other left or right on the LSD rear axels, but we couldnt order either to be sure since none of the retailers had any in stock or capable of being ordered.

!!!! If you collect a transmission from a year/model that is not of your own, such as in my case where I purchased a 2000 RS transmission for my 98, you MAY need to keep your speed sensor as the connector varies.

Step 2. Mechanical break down (Simple as dirt because this is covered in other DIY's in the forum)

remove the engine, trans, drive shaft and rear differential.

you will have to remove the shifter trim and seperate the automatic shifter from its arbetrary linkage, there will be a few bolts most likely stuck to some degree which you will need to seperate from the transmission, if you wish to sell it, you're gonna want to leave that sucker in tact. now, what you do with the shifter itself is up to you! As long as you leave the little clips with wires leading away from the shifter alone you will be fine.

Continue to split the Transmission from the engine if you didnt durring your original removal process.

At this point you can check your speed sensor on your transmission, if the replacement transmission has the same sensor you can keep it, if not, simply remove the old one from your automatic and put it in the manual trans.

If your automatic transmission is 98 or older, and your replacement transmission is 99 or newer you will notice that the transmission has 6 bolt locations wile your motor has 4.

This will cause no eminent threat to your project! it will cost you another 10-15 dollars. We had to tap a new hole into the starter and purchase a larger bolt to bolt the second end of the starter down, this also requires you to expand the hole on the 2000 MT5 Starter. This secures your starter properly and taping the whole larger doesnt hinder your future USDM WRX swap.

Obviously you will need to remove the torque converter and flex plate from your engine. and proceed to replace it with your matching clutch, pressure plate, and flywheel. You can now reattach your engine and transmission and put them back into the car. (If you haven't done this before, I suggest installing the starter after the engine/trans are securely in place, less to get caught on)

You will want to install the shifter linkage before you insert the drive shaft as its going to get in your way, kartboy bushings are great to do now rather than later. and since you're playing with it, go ahead and install the shifter. (leave the trim off till you're done)

Proceed to install the new rear differential and drive shaft, and reinsert the old axles (for the front, you may want to purchase new pins for the inner connection between the axles and transmission)

Step 3: Some assembly required

Now you're going to need to take apart the lower portion of your dash on the drivers side, and gain access to your ECU this will be under the passengers feet, covered by a metal kick plate.

Start by replacing the ECU (same years/trims will clip right in)

Next we will go over to the Pedal box

the pedals you should have purchased need to match your clutch cylinder, from my findings on the 98 (I haven't had the privilege to search other auto or mt5 vehicles other than my own and the donor car)

You will notice the TCU dangling there or bolted onto the Auto brake pedal, this has to be removed, but according to what I've read this controls your ABS system, removing it kills automatic ABS, one simple solution is to get a fully manual wiring harness, manual abs unit and controller. but that isn't so practical (unless you're doing a WRX swap in which case you really don't need to be reading this) regardless there is information about this problem at the top of the page to refer to, as information is found I'll add it to the DIY

IF I am assuming correctly, the manual brake pedal and auto brake pedal are the same, or I'm wrong and the 98 was wired for both pre and post brake pedal boxes either way you should get lucky and the connectors match or you have both in there, the clutch side on the other hand you wont be so lucky, you don't have a clutch switch. there are two options here. you will run a 12 gauge wire directly from the ignition to the starter (yes the starter on the transmission) OR you will run a wire from the ignition to the clip on the clutch pedal (standard spade connectors fit snugly) and run a corresponding one out, all depends on how much you trust yourself to start the car in neutral or with the clutch depressed.

Now for some more wire housekeeping, now if you return to your shifter area you will notice your funny little shifter wiring, ** due to me have lost the pictures I'll be blunt and explain till I get the visuals up** here you have 4 wires on one clip and two on the other, the 2 others light up an indicator to help you figure out what mode you are in, when its dark, its useless. the other 4 have a great purpose, 2 control a locking motor to keep you from exiting park wile the car is off and the other two dictate that it IS indeed in park, (this allows two things, ONE it allows you to take your key out, and two, it turns the fuel pump on, which is kinda important!), the simple mans way of doing it would simply be to take the two that activate the switch (easily known as the ones that DON'T go to the locking motor) and splice them together and retain the clip and plug it into the shifter harness and toss the shifter.

Finally we return to the engine bay, the following you will have to find wiring pin outs on your own, I will post the RS ones when I post the pictures

you will need the reverse lights, there is also the neutral position switch (I haven't looked it up but we believe its for cruise control which you cannot use any more), both send a signal, so one goes to ground one goes to the reverse light pin. best way to do this is to locate the Auto wires per those pins and splice them into the transmission sensor wires as you wouldn't want some one hitting you because your reverse lights weren't on. and that's it for wiring!

In a way you could almost say that you're done! BUT for obvious reason you will want to check and double check that all of your exterior lights are working as they should. Between now and when you turn the car on, please ensure you have emptied out and refilled both your differential and transmission with new fluid and unless you're crazy and lifted the engine with the radiator you're going to need to refill that as well.

And as per any DIY ESPECIALLY THIS KIND

I AM NOT RESPONSIBLE FOR ANYTHING YOU BREAK/SHORT/DESTROY DURING THIS PROCESS, OR ANY FAILURE OF THE VEHICLE DURING NORMAL OPERATION, NOR AM I LIABLE FOR YOUR VEHICLE IF ANY BREAKING SYSTEM FAILS AND/OR CAUSES AN ACCIDENT WHICH LEADS TO YOUR INSURANCE COMPANY REFUSING TO PAY DUE TO UNANNOTATED MODIFICATION OF YOUR BREAKING SYSTEM

****** I TYPED THIS ALL IN ONE SITTING I'M PROOFREADING IT AS WE SPEAK Images will be uploaded soon for now, here's a video of sleepysubie starting my car with no exhaust *****

Impreza 2.5 RS No headers - YouTube
 

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99' Impreza wagon-red
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Do you have a total cost estimate on this project? I am thinking of doing the same and would like to get a general idea on how much it would cost to do this. Thanks, Dan
 

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98 2.5RS ~ EJ257D Hybrid
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864 Posts
Discussion Starter #7
Cost varies too much to give a firm response

I purchased my setup from a guy doing a complete WRX swap, so he sold me everything in one big kit.

If you shop around there's no way you'll ever pay more than 1000 on an RS or WRX complete setup but this can be done for 5-700 if you try hard enough. check part outs or try to find people relatively close to you doing swaps, buying it all at once will truly save you time and money.
 

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99' Impreza wagon-red
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Cost varies too much to give a firm response

I purchased my setup from a guy doing a complete WRX swap, so he sold me everything in one big kit.

If you shop around there's no way you'll ever pay more than 1000 on an RS or WRX complete setup but this can be done for 5-700 if you try hard enough. check part outs or try to find people relatively close to you doing swaps, buying it all at once will truly save you time and money.
Thanks, that helps. I found a 93 impreza wagon locally for only $800 that I am thinking of buying but it is an auto which I hate, so we will see. Great writeup BTW
 

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2000 impreza, red, auto...
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hey...i have a 2000 impreza L looking to switch to manual....would it be the same for a L for somewhat similar or bettter yet know anyone seeling a coupe? 2.5 or L manual? for not alot? say something around 4500?

thanks
 

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98 2.5RS ~ EJ257D Hybrid
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864 Posts
Discussion Starter #10
Its the same process, consider the MT5 L's and outbacks use cable clutches, this guide is for hydraulic clutches so WRX and RS transmissions, you're spending the money to do this you'd be better off going hydro.

If you purchase a complete WRX or 2.5RS clutch master and slave cylinder/pedal box/transmission/drive shaft/rear differential/associated mounts/ GC shift linkage you'll be fine it all bolts right (for you at least, 93-97 cars may have a different plug for the brake light, I've never looked into it though)
 

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2000 impreza, red, auto...
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kool thanks i will be doin it in the near future maybe in the next 2 months :) thanks again for the info really appreciate it
 

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1994 Aegean L, 1998 Panda!
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Lovely writeup.

Just to confirm.

You cannot use your A/T drive shaft or front-rear CV half shafts?

You CAN use your A/T ECU but you must remember to take the car out of gear before you start it?

You need a M/T ECU for the reverse lights to work?

So basically, I can bolt in a M/T, flywheel, drive shaft, rear diff, rear CV shafts, clutch master and slave cylinder, pedal assymbly, and clutch-flywheel and have a solid setup?

I'd rather not go through swapping my ECU at the moment. Is the only reason for an M/T ECU only to keep the ABS, cruise control, and reverse lights?
 

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98 2.5RS ~ EJ257D Hybrid
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Discussion Starter #13
1. You cant use the AT Drive Shaft (because its 3 inches shorter than the MT5) But, you CAN use the CV Axels I used all of my 98 Auto CV axels and everything worked out fine

2. You can run full time with the Auto ECU there have been discussions on how to modifty it to get the ABS to work but its a slight hack job and I dont feel its a safe/reliable soltuion as it could become hazardous.

3. The MT5 ECU is needed only if you want to switch to an MT5 ABS pump and have proper ABS (although this hasnt been 100% confirmed as I've never seen any one do this) Reverse lights are simply wired in from the MT5 transmision wires no ECU requirement.

As long as you have all of the mechanical parts you can almost do a plug and play on your car, you have to bridge a few pieces of the Auto Harness to trick it into neutral and enable the fuel pump. You also need to bypass tha Automatic ignition switch. a simple way is just running straight from the ignition to the starter, you can also use spade connectors to clip in at the clutch switch (I recomend it if you're used to driving autos)

Unless you Swap a complete Manual Wiring harness you cannot have cruise control wile using an MT5 Transmission.
 

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1994 Aegean L, 1998 Panda!
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you have to bridge a few pieces of the Auto Harness to trick it into neutral and enable the fuel pump. You also need to bypass tha Automatic ignition switch. a simple way is just running straight from the ignition to the starter
Any idea where I'd get the wiring info from?

I don't have ABS or cruise control anyhow so I wont miss anything. I'm also used to driving manuals so I can't wait!

Thanks for the help.
 

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Wow thanks for a write up, I always ask these questions and this might answer it!
I've never seen a faq about this.

How much money we talking here:
-Hire someone or
-DIY?
 

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2000 STM 2.5RS
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759 Posts
Letze, I used a good part of you DIY to do my auto to manual, and would just like to thank you for your help! I did it over thanksgiving weekend and everything went smoothly! Love It. Only thing I am still trying to figure out is how to get my ABS back. Thats the only thing not working, we thought we had it wired to work correctly, but failed hah. Anyone thinkin about doin the swap, it is very well worth it!
 

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98 2.5RS ~ EJ257D Hybrid
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864 Posts
Discussion Starter #17
Glad everything worked for you. From what I'm told it requires a manual ABS pump to resolve this, I'm switching to non abs brakes as ABS has really caused me some grief in the past so I unfortunately wont be sitting around trying to figure it out. If my 2.5 motor wasn't toast before we did that video I might be more inclined but its already been torn down waiting in a bag to go to the machine shop

Cost is something that can differ heavily. I have sunk around 3800 or so in my car including purchase, I got extremely luck on a great deal of things, one being the car and then when SleepySubie hooked me up with a friend of his to get the 2000 RS motor, Trans, ect..

After the sale of the motor I have about 850 in the swap and that includes the kartboy stuff I ordered and the shifter bushings that got lost some how (like 30 bucks from the stealership), The engine is back out now because the clutch that came with it has about 80k on it and it was original. Which would throw the price up a bit. Another thing to keep in mind is I purchased mine locally and I picked it up with my truck, but if it has to be shipped something weighing that much gets to 200+ from freight companies usually more

You can ask around to the different shops for prices but labor is a premium its up to you if you can afford the luxury of having some one do the work for you.
 

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98 2.5RS ~ EJ257D Hybrid
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Discussion Starter #19
I need to get them from sleepy... I keep forgetting I'm gonna bother him again soon, and get them up car is currently ripped apart and stuffed full of parts during the winter otherwise I'd be getting them from the complete job
 

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2.5rs 2000 STM
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I need to get them from sleepy... I keep forgetting I'm gonna bother him again soon, and get them up car is currently ripped apart and stuffed full of parts during the winter otherwise I'd be getting them from the complete job
cool cool good info non the less
 
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