JDM driveline swap - Page 3

oab_au · #31 08-30-2012, 06:09 PM

Quote:

Originally Posted by 'E'

my bad its an oil temp sensor for the dccd system.

this link explains everything pretty well

http://www.igotasti.com/vBforum/show...-info-and-FAQs

That is a big write-up, but they still don't understand how the torque is altered by the LSC or when turning a cornor.

As they say.

"Subaru tries to tell us that by selecting different settings within the manual mode we are changing the torque split, this info is incorrect. When adjusting the manual settings you are adjusting the amount of center differential lock-up."

Subaru is correct.

Harvey.

longassname · #32 09-10-2012, 02:28 PM

And back to the original topic....actually there isn't much to post about it. I got the few little bits from the dealer I would have needed to install everything but haven't gotten a chance to do it.

The jdm transmission didn't come with axle stubs. I had ordered and gotten new axle stubs from the dealer a long time ago. I could swear when I've ordered them before they came with circlips on them but this time they didn't; anyway, I got the circlips and installed the axle stubs into the transmission. I needed a new rear differential cover gasket since I opened up the differential to check the gear ratio. I got that and a set of svx mounting studs so I don't have to pull them off of my svx rear end--so the rear end is closed up and ready to go in too.

There's no chance I can do the install this week but maybe I'll get a day next week.

Darren · #33 09-26-2012, 10:02 AM

Something that might be of use to some of you...the JDM type R and type RA Impreza and the later JDM 6 speed motorsport derived Impreza's use a manual DCCD controller so you have to adjust the rear to front bias totally manually with no auto control or setting.

icingdeath88 · #34 09-26-2012, 10:14 AM

Quote:

Originally Posted by Darren

Something that might be of use to some of you...the JDM type R and type RA Impreza and the later JDM 6 speed motorsport derived Impreza's use a manual DCCD controller so you have to adjust the rear to front bias totally manually with no auto control or setting.

Ok, people keep posting stuff like this and I really think it needs some clearing up. The way that DCCD works is not by adjusting the front to rear bias. It adjusts the amount of lockup of the center diff. The front to rear bias when unlocked, acting as an open diff is the 40/60 front/rear or whatever split, and when locked is not changed, it's just locked, so that the front and rear wheels have to move at the same speed. Now, it effectively changes the handling characteristics of the car in a way that can seem like the bias is adjusted, but that's not what's actually going on.

longassname · #35 10-09-2012, 02:05 PM

And back to the original topic...

I've installed the engine, transmission, and differential.

On the engine during the install I had to switch the hose barb for the brake booster from the right injector stack to the left injector stack which was easy enough but had escaped my attention before.

I had hoped the SVX axles would fit the 06 wrx rear differntial since both it and the svx units are vlsd r160 rear ends but they didn't. After they didn't pop in I looked up the vlsd carrier and see they are different part numbers. I ordered a set of 06 wrx sedan rear axles which should show up any minute now. I could have swapped the svx vlsd carrier into the wrx rear (and re-set up the gears and pre-load) but I'd rather change axles than take the differenital back out and set it up with the other carrier.

longassname · #36 10-14-2012, 05:46 PM

I think my 06 wrx sedan rear axles will be delivered tomorrow so I went ahead and pulled the svx rear axles out of my car to get it 100% ready for the new axles to go in.

I also went ahead and swapped the case bottoms from my us svx ecu and tcu with my JDM FA TCU and 9A ECU. I've already chipped my JDM TCU but have the stock firmware on the installed ROM to start with. The JDM ECU board doesn't have a socket pre-installed in it like the US board does so I would have to socket it in order to modify its firmware. I don't see any reason why JDM firmware won't work on a US ECU though so after everything is test driven and proven I will swap my US ECU circuit board back in and load it with the ECUtune JDM Stage1av1.

So the car is all full of fluids just waiting for rear axles to be able to drop it to the floor and drive it off.

Tireiron · #37 10-14-2012, 08:27 PM

Good luck with the rear axles, but I'm worried they may not fit... The SVX uses the larger 190 rear parking brake with the larger rear bearing. I believe the WRX, even with the FHI brakes, still used the 170 rear parking brake with the smaller bearing. That is the reason the 05 to 07 STi rear axles bolt in when swapping to a R180. For your sake I hope I am wrong and it will work for you.

longassname · #38 10-14-2012, 09:54 PM

Well, I know nothing about Imprezas and it sounds like you do so I'm guessing I'll run into the problem you are expecting me to. Sounds like I may have to swap the SVX carrier into the WRX rear end.

Quote:

Originally Posted by Tireiron

Good luck with the rear axles, but I'm worried they may not fit... The SVX uses the larger 190 rear parking brake with the larger rear bearing. I believe the WRX, even with the FHI brakes, still used the 170 rear parking brake with the smaller bearing. That is the reason the 05 to 07 STi rear axles bolt in when swapping to a R180. For your sake I hope I am wrong and it will work for you.

Tireiron · #39 10-14-2012, 11:24 PM

Well the SVX VLSD is a much better unit than the WRX one if that matters to you. Does the left side SVX shaft fit into the WRX diff? I know the right side should have the extra neck down spline section so there is no way it would fit. If the left side fits into the WRX carrier you may be able to get away with using 2 left side SVX shafts with the WRX R160.

So you may have to pull it out and swap the SVX carrier into the diff with the correct gears (at least you shouldn't have to mess with the pinion gear, just the ring gear and backlash).

SVX axleshafts for reference, which I'm sure you have seen in person now. The longer one is the right side.

The WRX uses matching shafts left and right, so no tapered extra spline section. If the outer end of the 06 WRX shafts is too small to fit the hub of the SVX your only options will be to use the SVX shafts and the SVX VLSD carrier OR get the custom made aftermarket shafts for the R160 diff with the large hub brembo swap for the WRX guys that want to put on brembos by swapping outer knuckles but don't go to R180 diffs.

longassname · #40 10-15-2012, 07:50 AM

Do you by chance have a link to a digital copy of a factory service manual section on the axles for an 06 wrx sedan?

Why do you say the svx vlsd carrier is better than the wrx vlsd carrier?

Tapani · #41 10-16-2012, 10:47 AM

Quote:

Originally Posted by Tireiron

Does the left side SVX shaft fit into the WRX diff?

It might not.

I do not have all the details, but the "more recent" inner CVs (from an open diff) I have seen and tried were identical LH/RH ,had a longer splined sections and the C-clip groove is axially at a different location.

The Quaife Torsen I have has two sets of grooves - one for the "more current" (open diff) half shafts and one for SVX type VLSD shafts with the extra bit cut off. Also, the grooves are of different cross section - the RH SVX side needs the C-clip to into the carrier and the LH side stays on the shaft. The grooves are chamfered a bit differently. I trust the "more recent" stay on the shaft on both sides.

Tapani

Tireiron · #42 10-16-2012, 02:03 PM

Yea the newer symmetrical axleshafts have the c-clips stay inside the differential.

The SVX carrier and shafts are very similar if not the same inner as the old JDM mechanical LSD carriers.

I don't currently have a FSM for the 06 WRX, just the bugeye 02-03 (including the supplement for the JDM spec-c bugeye 01-02) and of course the SVX and the 2nd gen Legacy.

I've had lots of experience with the WRX rear diffs compared to my SVX rear diff and the lockup of the SVX when warm is much more pronounced and noticeable. The WRX VLSD is almost no better than an open diff. Any of the WRX owners who really need the traction of a LSD swap to some form of mechanical LSD such as the R180 STi or the old JDM mechanical if they can be found (cheaper to get a R180).

Hopefully if the weather is nice Saturday I will be swapping my R180 and whiteline lateral links and trailing arm bushings in along with the STi R180 rear axleshafts. All in preparation for the 6MT soon to be in with the supercharged motor...

longassname · #43 10-16-2012, 03:16 PM

Trusting Tireirons info about the hub bearings to be correct I arranged to return the wrx axles without opening them and picked up another dif cover gasket from the dealership. It looks like the info about the SVX vlsd being superior to the wrx vlsd is most likely correct so I'm happy with the decision to use the svx vlsd. It obviously has MANY more plates than the wrx unit.

I installed the 3.7 ring gear onto the svx vlsd and installed it into the wrx case with the svx bearing retainers and shims. Since A and B were both zero for both cases this guaranteed the bearing pre-load would be correct and the backlash and contact pattern on the gears should also come out right. I used GM bright yellow gear matching compound to check and the contact pattern and backlash looked great. I didn't actually measure the backlash but you can get a good reading on backlash by where the contact pattern is and how it moves as you apply a load to the gear.

I installed the axles into the diff on my work bench and lifted the whole rear end assembly into place with a transmission jack.

There are no transmisison or engine error codes and it runs and drives without any issues. The car definitely feels different with the rear bias of the vtd.

Tireiron · #44 10-16-2012, 05:30 PM

Yea I can't wait to get my JDM 6MT in there with the DCCD bias in it. We swapped a US 6MT into my friends bugeye without a DCCD controller and you can really feel both LSDs (front and rear, cant wait for mine) and the DCCD being locked up in parking lots on tight turns. It really makes the car feel different on long tight curves like exit ramps too. Tightens things up and makes it more oversteer prone, which is nice in a car that has WAY too much understeer.

That 3.70 that you have is an awesome ratio for the SVX and highway RPMs. I hope you really enjoy it, I'm out of luck with a 3.90 final drive and one of the shortest 6th gear ratios ever used. It will at least keep me slowed down some on the highway I guess. Gotta stay out of boost while cruising or I will empty the water/meth tank too fast.

Keep us posted on if you find any differences once you get into things with the JDM motor and electronics more. I don't expect much of a difference in the motor at all but the ECU may be a world apart once you start playing around with it.

icingdeath88 · #45 10-16-2012, 05:46 PM

Quote:

Originally Posted by longassname

Trusting Tireirons info about the hub bearings to be correct I arranged to return the wrx axles without opening them and picked up another dif cover gasket from the dealership. It looks like the info about the SVX vlsd being superior to the wrx vlsd is most likely correct so I'm happy with the decision to use the svx vlsd. It obviously has MANY more plates than the wrx unit.

I installed the 3.7 ring gear onto the svx vlsd and installed it into the wrx case with the svx bearing retainers and shims. Since A and B were both zero for both cases this guaranteed the bearing pre-load would be correct and the backlash and contact pattern on the gears should also come out right. I used GM bright yellow gear matching compound to check and the contact pattern and backlash looked great. I didn't actually measure the backlash but you can get a good reading on backlash by where the contact pattern is and how it moves as you apply a load to the gear.

I installed the axles into the diff on my work bench and lifted the whole rear end assembly into place with a transmission jack.

There are no transmisison or engine error codes and it runs and drives without any issues. The car definitely feels different with the rear bias of the vtd.

Very cool, glad someone finally did this without any gigantic issues. I like how methodical you are with everything, and thanks for sharing, I've learned a ton from you over the years.

Quote:

Originally Posted by Tireiron

That 3.70 that you have is an awesome ratio for the SVX and highway RPMs. I hope you really enjoy it, I'm out of luck with a 3.90 final drive and one of the shortest 6th gear ratios ever used. It will at least keep me slowed down some on the highway I guess. Gotta stay out of boost while cruising or I will empty the water/meth tank too fast.

You will love the 6mt. And you will go real slow on the highway. Uses a lot of gas too.