02 wrx trans hydraulic conversion

Flywheel, Clutch, Transmission, Axles, etc...

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91Legacyresto
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02 wrx trans hydraulic conversion

Post by 91Legacyresto » Wed Mar 27, 2019 8:43 pm

Finally I have finished my trans swap. This is just a small write up of how involved it was to install the hydraulic clutch n trans without the factory holes in the firewall. I couldnt find much info on this so I'm hoping this might help somebody else trying to do the same thing.

We all know most ej transmissions bolt right up to any ej engine. There wasnt any issues connecting the transmission, bolting the crossmembers, rear diff, and axles were all the easy part.

The more difficult part was getting the correct alignment for the hydraulic clutch. What I ended up doing is using a donor or "firends" car so I could trace the body lines on the fire wall and mark out the holes. Took me about 3 to 4 time of tracing to get my template just about perfect. All ibused was a piece of paper to start then transferred that over to some cardboard. Held the cardboard up inside of my car and maked out the holes with a sharpie. Took a drill and drilled out the holes to proper size. Luckily I did it right the first time and got my holes to be in the perfect position just like factory.

Another small modification I had to make was the wiring harness on the inside of the cabin under the dash. Being an automatic from factory, theres a white plastic piece holding it up but exactly in the way for the pedal assembly to mount. So I had to cut and break the plastic far back enough so I could tuck the wiring up above the pedals and not in the way. Wasnt too bad, and I only copped one wire in half while doing it, that wasnt real easy to solder. So try not cut anything lmao.

The wrx clutch reservoir bolts up nicely but the pressure lines have to sit ontop of the trans and theres nowhere else to mount them. It sits still and doesnt move around. All in all the clutch system works way better than expected and the trans isnt all beat up like most wrx trans are. If you have any questions then go ahead and ask away. Hope my pictures are well enough layed out for you all.

Clutch I used was a stage 2 clutch, I can pull it up if anyone's interested which one I went with. The pressure plate was a little heavy for the first 2 shifts, after that I got use to it while driving. Cant believe how much of a difference it makes going from a cable to a hydraulic clutch.ImageImageImageImageImageImageImageImageImageImageImage

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91 LS Turbo Project

mike-tracy
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Re: 02 wrx trans hydraulic conversion

Post by mike-tracy » Thu Mar 28, 2019 3:30 pm

Thanks for the write-up and pics! I had a clutch fork crack on my 98 OBS, and I used the opportunity to switch to Hydraulic. I agree with you, it's so much smoother and nicer engagement now
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote:
Mon Jan 14, 2002 10:23 am
Wait....I'm confused now.

Legacy777
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Re: 02 wrx trans hydraulic conversion

Post by Legacy777 » Thu Mar 28, 2019 5:50 pm

Thanks for sharing and posting the pictures.

For yours and others reference I made a template for this exact purpose when I did my AWD & 5spd swap.

I have the template in AutoCad, PDF, & JPEG. You can access them at the bottom of the link below.

https://www.surrealmirage.com/subaru/sw ... drivetrain
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

91Legacyresto
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Re: 02 wrx trans hydraulic conversion

Post by 91Legacyresto » Thu Mar 28, 2019 6:36 pm

I'm happy to help out this community in any way I can as I've gathered tons of info and help from others on here over the years. Anything to keep these old cars alive

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Urabus93ss
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Re: 02 wrx trans hydraulic conversion

Post by Urabus93ss » Mon Nov 11, 2019 8:24 am

What did you use for the clutch pedal assembly? How did you go about the speed sensor in the wrx trans?

mike-tracy
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Re: 02 wrx trans hydraulic conversion

Post by mike-tracy » Mon Nov 11, 2019 6:53 pm

The mechanical speed sensor screws right in where the electronic one goes.

As for pedals, a perfect fit of course would be from a 91-94 SS. You can get most of the bolts to line up from other 1990s cars with hydro pedals, such as the 98-01 impreza RS, 97-99 Outback and Legacy GT, or 1st gen Forester.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote:
Mon Jan 14, 2002 10:23 am
Wait....I'm confused now.

Legacy777
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Re: 02 wrx trans hydraulic conversion

Post by Legacy777 » Mon Nov 11, 2019 6:55 pm

Welcome to the BBS.

You should be able to use any hydraulic clutch pedal assembly from a modern Subaru. You remove the speed sensor and install an adapter that hooks up to the speedometer cable. I'm pretty sure that adapter and part number are floating around if you need the part number.

EDIT: Looks like Mike beat me to the post :P
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

Urabus93ss
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Re: 02 wrx trans hydraulic conversion

Post by Urabus93ss » Sun Dec 08, 2019 3:47 am

Mkay, thank you for the info! My 93 ss is already manual swapped, but its cable operated and have been planning the wrx trans swap to keep it 5x100. I'll try and find that part number for the adapter, i just want to keep the dash gauges working

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