Whats the difference between R160 & R180 diff?

AlpineRaven · Post by **AlpineRaven** » Tue Dec 08, 2009 9:14 pm

what is the difference between R160 and R180 rear diff?
I've always said "oh yeah they'll fit etc" But i wanna clarify whats the difference between these two.
Cheers
AP

rtcb65 · Post by **rtcb65** » Tue Dec 08, 2009 9:46 pm

I dont know if this is right or not, i found this and it said one was a r160 and one was a r180.

Tis is just a wild guess, the 4.44 gears wont fit in a r160, so with a wild guess, they made a bigger diff case to take them. Which is the r180. There is a better than good chance that i am wrong , so dont believe it. Wait for someone to back it up first.

AlpineRaven · Post by **AlpineRaven** » Tue Dec 08, 2009 9:57 pm

Ah okay,
Its because in my garage I have R160 (same as left side diff) with 4.44 final drive. The guy I bought it off he said its R180, but when I received it, it was normal R160 which I noticed.
Cheers
AP

tex · Post by **tex** » Tue Dec 08, 2009 10:24 pm

The datto forums might help too. But the impression I got was the mountings etc were very similar although looking at the size differences the cv length would be different. I hate to whore your thread but did you score an LSD. And do you know if any of the autos came out with an LSD in the front or centre diff.

GOD · Post by **GOD** » Tue Dec 08, 2009 11:55 pm

From my understanding, the number refers to the diameter of the crownwheel in mm.

Dane.

AndrewT · Post by **AndrewT** » Tue Dec 08, 2009 11:57 pm

I dont think any of the internals are interchangable. Generally everything is just bigger and beefier. You can get all the bits you need to make it bolt straight into an EJ subaru by stealing them from a donor STI if you find a model which came with R180 stock, bit expensive tho. Some guy was selling a conversion kit on rslibertyclub and I think he wanted around 1600. Need to swap shafts, hubs everything.

vincentvega · Post by **vincentvega** » Wed Dec 09, 2009 8:31 am

there are plenty of R160 4.44 diffs. my car has one

bigger, stronger, mor eexpensive pretty much covers it. Not necessary unless you are making big power and transferring a lot of torque to the rear wheels (VTD auto / DCCD manual)

AndrewT · Post by **AndrewT** » Wed Dec 09, 2009 10:12 am

vincentvega wrote:there are plenty of R160 4.44 diffs. my car has one

bigger, stronger, mor eexpensive pretty much covers it. Not necessary unless you are making big power and transferring a lot of torque to the rear wheels (VTD auto / DCCD manual)

u mean R180?

bluesteel · Post by **bluesteel** » Wed Dec 09, 2009 10:28 am

R160... 160mm Crownwheel Diameter, comes in all ratios and lsd's

R180... 180mm Crownwheel Diameter, comes in all ratios and lsd's

physically the same mounting points, but the R180 is a bigger casing, and the R180 used beefier outputs for the driveshafts too

no parts are interchangable between them (except i think the flange that goes to the tailshaft)

bobbyjimmy · Post by **bobbyjimmy** » Wed Dec 09, 2009 11:22 am

http://www.gotitrex.com.au/home/Blog/r1 ... rsion.html
Shows the physical differences and abit about the ratios etc.

vincentvega · Post by **vincentvega** » Wed Dec 09, 2009 12:21 pm

AndrewT wrote:u mean R180?

2 seperate points. could have been clearer

1. R160 4.44 exist

2. R180 bigger stronger etc

81GGR · Post by **81GGR** » Wed Dec 09, 2009 1:53 pm

if you are going to convert from an r160 rear diff to an r180 there are a few ways to do it. to do it properly you have to replace the diff, drive shafts and hubs, brake rotors and brake calipers (the handbrake assembly on the rear hub is a different size to the r160 set up and unless you have 2 pot brakes - the mounting points for the calipers on the hubs are different too.

the physical dimensions of the set ups (track width, the length of the diff, the mounting points etc) are all the same for r160 and r180 but the r180 diff is bigger and the driveshafts are thicker etc etc. (ie it is tuffer).

you can just replace the diff and shafts to convert to r180 if you change the splines on your existing hubs - but it is not a straighforward mod and your hubs might also need some machining so the dust rings on the shafts are effective.

also, where the tail shaft bolts on to the diff is a different stud pattern. but you can swap the one off your r160 onto the r180 to save getting a new tail shaft.

i have the r180 rear end in my forester (plated lsd) and it is a massive improvement over the r160, although i am using a 6 speed dccd box and front lsd too which adds even more handling improvement when your are really leaning on it.

YouTube · Post by **El_Freddo** » Thu Dec 10, 2009 6:16 pm

So from what I understand from this thread for the R180 diff:

1) Its the same width as the R160

2) Its larger in height to accommodate the larger crown gear

3) A change of the inner CV/cups will have the R180 fit into the back of your subi. Would this work for an L series?

Cheers

Bennie

YouTube · Post by **El_Freddo** » Wed Dec 16, 2009 3:39 pm

So no one can confirm the above??

Bennie

discopotato03 · Post by **discopotato03** » Wed Dec 16, 2009 4:28 pm

Those long nose R series differentials are based on Nissan/Datsun diffs , ask Coxy here as he's more Nissan or Vulcan than human and knows heaps about R160/180/190/200 differentials .

From memory differentials are measured on the ID of the crownwheel where it fits over the register on the hemisphere .

As a side note a larger and heavier differential than is necessary achieves absolutely NOTHING for you . IMO if you're not breaking R160's use those .

A .

GOD · Post by **GOD** » Wed Dec 16, 2009 6:50 pm

discopotato03 wrote: As a side note a larger and heavier differential than is necessary achieves absolutely NOTHING for you .

Except that there are lockers available for R200s, and possibly R180s too. Handy for the off-roaders among us.

Dane.

YouTube · Post by **El_Freddo** » Thu Dec 17, 2009 5:05 pm

Yep that's it GOD. I checked out the ARB listings and they don't do one for the R180 or R200

I did find someone to make a vacuum locker but it still looks like its not going to happen either

Cheers

Bennie

discopotato03 · Post by **discopotato03** » Thu Dec 17, 2009 5:55 pm

Maybe what you should be doing is asking around in Datsun Rally circles about plate LSD's with lots of pre load and maybe altered ramp angles .

You can make a plate LSD more agressive and if it wasn't being driven ie part time 4WD that probably wouldn't matter .

It sounds like a lot of work to graft an R180 or R200 into an L Series and it would cost a bit dependand on tailshafts and half shafts . THEN you have to mod the hemisphere .

Still a pitty these cars didn't have the park brake at the back , um hydraulic rear handbrake and poor mans traction control ?

Cheers A .

YouTube · Post by **El_Freddo** » Thu Dec 17, 2009 6:02 pm

Yeah Disco, the high preload LSD would be ok, but after having the welded rear diff off the black top and aiming to have an AWD box (also sick of pulling over and getting out to put the shaft in to lock the rear), an air or vacuum locker would be the go, it can be done on the fly too which is what the subaru has been designed to do as well

Just got to think outside the square...

Cheers

Bennie

discopotato03 · Post by **discopotato03** » Fri Dec 18, 2009 7:49 am

I went through this years ago with the turbo FJ powered Bluebird I had .
At the time Nismo plate LSD's were very expensive so managed to track down a Detroit Locker for the H190 diff it had at that time . Brilliant traction but they are either locked or unlocked and go from one mode to the other without warning at times .
I eventually got hold of a plated up H190 LSD center and it was good though it did want to bind up taking off in low gears around courners - uphill corners .

All ways to eliminate spin have compromises . The trouble with locked centers , no matter how you achieve it , is that it can transmit all the torque from the tailshaft to one wheel/hub/driveshaft and they don't always like it . It also puts major loads on suspension and locating points , my Bluebird was opening up the rear body seams and trying to break the suspension links at the body ends .

I know I'm sounding negative but these are potentially some of the things you find in vehicles with a unibody rather than a chassis like a Rover or Tojo has .
The other thing is that where an LSD tries to limit slip the locker is either open or locked and nothing inbetween .

I've never had a Torson diff but they are supposed to be one of the best compromises and I think someone here in Oz has or was making then for custom applications . It may have been Modena in Victoria and the ask may have been 1300ish .

It gets really interesting with AWD cars because at times the three diffs want to fight each other and that can lead to all sorts of unpredictable handling issues . This is often why the manufacturers use VLSD's and they are reasonably gentle in their operation . They absorb transmission backlash and gently place a slight LSD action which is all your average need to be seen as a SUV pilot wally wants .

I could go into use a better tool for the job but thats not what the Subaru brigade wants to hear .
No doubt you have been into "trail repairs" to get where you want to go .
May sound silly but I reckon people could do worse than to make long lightweight ramps and carry them on roof racks . Maybe with some sort of link system so they could be extended if necessary - more sections in back of wagon ? Tirfor type winches are great recovery gear and possibly made small and light enough for an L Series . With a high lift jack and some trenching tools and a mattock you get most sane places with a bit of work .
The trouble with Subarus is they are designed to be road cars or softroaders meaning short suspension links and limited ground clearance . I don't think any road based unibody car ever made a good off roader without a lot of money thrown at it and then there are still compromises .

Cheaper and easier to improve the path and or drag it through with a winch I reckon . Skid plates required underneath too .

A with the flack jacket donned ...