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Rear Discs, size of coupe rotors?


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Where as the General has the facts down to a science.

 

Well - I don't know that I would say that.... upon closer inspection it appears that (as usual) things are a lot more complex than a simple yes or no....

 

From my parts manual quick reference (1985-1998) the specifications are thusly:

 

Rotors are listed as all the same: #25431GA180

Pads are listed as all the same (kit): #25191GAf32

 

Calipers are the difference:

 

(RH = Right Hand, LH = Left Hand)

 

RH(25110GA180) LH(25190GA010): 12/1986 - 3D 4WD, RX; SW GL, GL10, 4WD

RH(25110GA182) LH(25110GA381): 1/1987 - 3D GL, RX, RS; SW DL, GL, GL10, 4WD

RH(25110GA372) LH(25110GA382): 3D GL; 4D; 3D DL, RX; SW DL, GL, GL10

 

So not only is it a model thing, but also a year thing. But it does appear that the Sedan (listed as 4D) only got the smaller ones.... but so did 2WD's.... heh - they list a 2WD RX:rolleyes:..

 

So I guess you can say that the Sedan, and ALL 2WD's got the smaller calipers. Not that anyone gives a hoot about 2WD rear discs, but I figured I would look. What do ya know - learn something every day!

 

Also interesting to note that the only difference in 2WD vs. 4WD disc assembly's is the hub, and possibly the backing plate, but I think that's only different because you need the 2WD calipers to go with em, which are the same as the 4WD sedan calipers, so assuming you get an entire set from a 2WD, and replace the hub with a 4WD disc hub it *should* fit. At least that's my theory...

 

GD

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Btw, this 3 door at the junkyard is an interesting fellow. Its a 4WD Turbo, but doesn't have a designation like GL or DL. It just says Subaru. Plus, its got a 3.7 part time D/R in it. And looking in the owners manual that was in the glove box, its got the same crappy low range that the RXs have, 1.2. NOT the 1.5 found on the 3.9 D/R box.

 

I'm not saying where its at, cuz the LSD on it is mine. You heard me, MINE. After Saturday, it'll no longer have an LSD on it, cuz it will be making its way onto the XT.

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and if the calipers are smaller but the pads are the same, then the difference must lie in how much pressure the calipers exert.

 

That would seem to be the difference - but wouldn't it have been easier for Subaru to just change the proportioning valve? hhhmmmm - still a bit of a mystery really.

 

You sure that thing isn't a 90 Loyale RS?

 

GD

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Its an 86. Prod date of like 10/85 I beleive. Its a strange bugger.

 

What's strangest to me was the 3.7 d/r part time 4wd transmission. If it didn't have the crappy low range, I considered making my wagon 3.7 for better gas milage.

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Its an 86. Prod date of like 10/85 I beleive. Its a strange bugger.

 

What's strangest to me was the 3.7 d/r part time 4wd transmission. If it didn't have the crappy low range, I considered making my wagon 3.7 for better gas milage.

 

Standard equipment for an 85/86 RX - they didn't become FT4WD till 87. It proabably is one of the few "not-RX's" out there. Not labled per-se, but still has all the features.

 

GD

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l have one of the 3.7 part time 4wd d/r boxes from an RX sitting in my shed awaiting fitting. From what l could gather these were available on 85/6 RX's here in Aus and run the bigger Turbo cv's as opposed to the standard type 5 speed dr 4wd.

So, getting back to the subject at hand, where does the vortex/xt rear disc set-up slot in?

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So, getting back to the subject at hand, where does the vortex/xt rear disc set-up slot in?

My 4WD XT Turbo is the larger size. I'd assume it follows the same as GD says, and that the 2WD would have the smaller calipers, and the 4WD have the larger. Just like everything else except the sedan.

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