R31 Skyline and Pintara diff conversions

[70rolla]

im looking to do a diff in my ke i was going to just go a t series
but i am wondering about r31 diffs as i spoke to a friend who owns a diff
place and he told me too look into a pintara or 31 diff ? saying they are easy to get parts for there lsd and disk brake rear end he is currently looking into prices and what it would cost all up to do a 31 diff aswell as the t series


can anyone shed some light or there thoughts on this



cheers

[meadan]

I have an r31 diff sitting under my house.

The disc brakes dont look too fantastic, they dont have an internal drum so you would need a hydro handbrake for any kind of drifting.
I dont think good lsd's for them are cheap either, but with a locker I doubt youll ever snap an axle, theyre BIG mofo axles.

I ended up going t-series instead because of all the effort it would have taken to fit it. Its not really worth it unless you have big power which will break the t-series.

A few things which need doing to make it fit;
-weld new mounts on it
-get it shortened if you want to keep standard track (its only about 10mm wider)
-make something up to adapt the handbrake cables
-custom tailshaft

[70rolla]

yer ive heard there longer i think they are a borgwarner but the guy i spoke too is a mate of my dads over at diff technics in kogarah
he said that he would rather put somthing like this in but it does seem like a lot of effort

[meadan]

yeah pretty sure theyre a borg warner.

Really it depends what you need it for. It will probably end up costing the same as setting up a t-series to be in new condition, just depends whether theres a chance youll break it.

[Sam-Q]

yes Borg Warner or a bog warmer as their known. Cast housing, pressed drums, medium size disks and by memory 32mm wider per side.

The handbrake mechinism is nothing short of shocking and how they even passed the ADR rules at the time is a mystery.

The pintara diff has the better ratios however they have smaller diameter axles.

[matt99]

Sam's about on the money with the width.

Its rare to find LSD's factory (possibly silo's had them?), Mini-spools are only $100 delivered for them anyway. Terrible handbrakes due to discs, or you can directly upgrade to a VS commo caliper if you want. I run twin rear VS calipers on mine (one HB and one brake).

If you want to do it, shorted one side so that it runs two passenger side axles (one side is longer from factory), and you will also obviously swap mounts. Unless you have something a bit beefier than a 4AG its not worth it really.

Pintara- 25 spline axle. 4.11:1 ratio.
Manual Skyline- 28 spline axle. 3.7:1 ratio.
Auto Skyline- 28 spline axle. 3.9:1 ratio.

The crown wheels and pinions are interchangeable, so you can swap things to use 4.1 ratio and retain 28 spline axles if you wish.

And meadan, they still snap axles, it just takes more effort.

[meadan]

haha you know your doing well when you break them though, theyre huge compared to the t-series.

I didnt know about it having different length axles though, I never took a close look at mine.

PM me 70rolla and you can have it for free if you want. Also have a spare housing you can have the mounts off.

[matt99]

Yeah, 4th gear in a SR powered 86 does that. Haha.

Free 31 diff? Where you from?

[meadan]

haha yeah that'd do it.

And im in sydney, i had it for sale for $20 bucks for ages, noone wants it...

[matt99]

Haha, ill pay postage. Is it complete? Whats it out of, Auto Skyline?

All the "boys" down here take them/the centers for "da brakies" in the commo's.

[meadan]

Umm not sure what its out of, I got it with my car as spare.

Its pretty complete, but has been taken apart. I have the brakes, centre and axles in a box.

I can go count the splines tomorrow if you want, where are you at?

[matt99]

Melbourne.

Yeah, if you want to scheck if the axles are 25 or 28 spline that would be much apreciated. Depending how much freight will be and whatever you want for it, I would definatly be interested. Although you did offer it to 70rolla first, so if he still wants it, I dont mind. Otherwise, gimmie.

[Sam-Q]

from what I have been told the Silloette LSD is a cone design which wears out very quickly and doesn't lock very hard.

One axle is indeed longer than the other but it is a very bad idea to run two short axles and shorten the housing the 50mm or so to make up for it. This is because the short axle is in the long axle tube, yes I know it's confusing but it's due to the shape of the cast center. The diff pinion is already offset to side by about 30mm. By running two short axles this makes the center around 80mm off to one side which is a lot and apart from potential clearence issues you have the uni-joints running at an angle. The more proffesional way to shorten the axle tube that has the short axle in it. Now due to the shape the axle is you can not shorten an axle any less than 50mm as there is no material there to cut a spline into. So most likely for many of the people here they either flare their gaurds or they shorten the long tube with the shorter axle.

For people who want it narrower again you can put the short axle in the long side and shortened that and then get another short alxe and get it reduced by the minimum 50mm for the other side. This will give you a 1370mm diff which happens to be ideal for a TA22 and probably also pre ke70 corollas. It also sits the tailshaft and housing in an ideal location.

The breather hole also needs to be relocated as it ends up under the spring seat.

Now the god-aweful handbrake- it's not necessarily because it has disks, it's just a shocking design. To set the handbrake pad pre-load the piston is wound in and out much like an ae82 twinky, nothing out of the ordinary there. Here is the where the usual dumn nissan engineering comes in, the caliper piston has only one slot going down it. This means the adjustment of the handbrake has to be done in 180 degree intervals. So lets say the pads can be just short of fitting over the disk, you wind it in another half rotation and then most of the actuators travel is to just take up the gap between the pad and the disk. On the very small bright side it's easy to adapt unmodded S series cables with a tube spacer to the nissan calipers.

Now some other things:

- Nissan studs use a 1.25mm pitch unlike the 1.5mm toyota standard

- It's a bloody heavy thing as it has the crude cast center with welded tube deisng instead of the full fabricated housing.

- the AE/KE S-series diff pinion fits onto the r31 diff!! I would of beleived it had I not done it myself, comes straight off and swaps as it's the same spine coming both from Borg Warner.

[70rolla]

sounds like a complete fuck up to me and i wasnt all that pleased with the idea in the first place but he seem addament on looking into it

i think its a complete waste of time as a toyota diff would be far easyer to put back into a toyota no cutting down and shit but anyways ill se what he comes back to me with in the way of
a $$ figure


im not liking the idea

[ke_70]

whats the cost like to shorten a diff?

[matt99]

Sam, I see what your saying. As usual your theory is correct and as usual I do things anyway and as... sometimes(?) it works. Haha.

I use a 31 diff in my 86, shortened one side, tailshaft on a dog of an angle and its still fine, uni's are still loving life and there replaceable anyway. I plan on doing exactly the same thing again with my next 31 diff. It goes without saying though, you are right, its propbably putting strain on the uni's in all the wrong ways. I think if your pushing big power out of a corolla, a hilux ( G ) diff is probably more suited as its stronger again, centered and is shorter to begin with. I just preffer the 31 diffs for ease of "mini-spoolisation" my handbrake set up, and availiblity (sometimes).

Clay, theres a guy down here with a jig who shortens them and swaps corolla mounts onto them for around $500-$550 I THINK. Mine was done by someone else, so im not 100% sure on that price.

[Sam-Q]

sounds like a complete fuck up to me and i wasnt all that pleased with the idea in the first place but he seem addament on looking into it

i think its a complete waste of time as a toyota diff would be far easyer to put back into a toyota no cutting down and shit but anyways ill se what he comes back to me with in the way of
a $$ figure


im not liking the idea

well depends on what you want to end up with. How much strength do you need?


Ke_70: to shorten and respline an axle is around $150. I had no difficulty shortening a housing on both sides myself and there are plenty people more skilled out there than me

[Sam-Q]

Sam, I see what your saying. As usual your theory is correct and as usual I do things anyway and as... sometimes(?) it works. Haha.

I use a 31 diff in my 86, shortened one side, tailshaft on a dog of an angle and its still fine, uni's are still loving life and there replaceable anyway. I plan on doing exactly the same thing again with my next 31 diff. It goes without saying though, you are right, its propbably putting strain on the uni's in all the wrong ways. I think if your pushing big power out of a corolla, a hilux ( G ) diff is probably more suited as its stronger again, centered and is shorter to begin with. I just preffer the 31 diffs for ease of "mini-spoolisation" my handbrake set up, and availiblity (sometimes).

Clay, theres a guy down here with a jig who shortens them and swaps corolla mounts onto them for around $500-$550 I THINK. Mine was done by someone else, so im not 100% sure on that price.

I see what your saying and fair enough. So no floor clearence problems? I suggest getting an axle shortened next time as for the money it's really quite cheap to fix things up.

[maxhag]

In my 86, I Have a R31 (28 spline), shortend, with a Kaaz 2 way LSD centre. As mentioned, the tailshaft is on a slight angle, hasn't been a problem..... I am happy with the setup, but the R31 brakes are shit. They wont lock the wheels for shit. It cost i$1500 to get the diff housing supplied,shortend, mounts relocated.....

[Sam-Q]

$1500 is a bit steep, did they do the tailshaft, adapt the brake lines and handbrake cables?

[70rolla]

theres absolutely positively no way that i will be paying 1500 id rather go t series ill let you no how much it will cost when he gets back to me tommorow with the price

[matt99]

No floor clearance issue until it was on its guts, then I just had the same issues as I did with a T series, nose hits under load. Fixed with adjustable trailling arms.

$1500 seems WWAAYY out, unless that includes an aftermarket LSD.

[70rolla]

My quote was way over $2000. With kaaz 2 way

[drift kid]

i know im opening an oldd thread, but im keen to put an R31 diff into my ae86 as i will be doing an SR20det conversion too so thats the reason i wont be going t series, id just like to have a guide as to how to shorten the diff properly, ive read here that one axle is shorter than the other so if i was to put one of these into the other side and shorten the housing to suit i would assume that it would be good, but Sam-Q has been talking about it not being a good way to do it due to the centre being offset i think, that is what i have gotten from the prior discussion, can someone please try and clear it up, maybe a diagram? sorry to be difficult guys but this seems like a pretty cheap/easy way to get arround snapping axles lol, and im not worried about the braking problem, i can sort that out and the mounts too.
Cheers for any help :)

[Sam-Q]

no diagrams but this describes in detail what you need to do:

http://s-86.com//s-articles-r31diffs.html

for you buy a long axle, shorten the short diff tube 50mm and get the axle cut and resplined to suit

[drift kid]

thank you very much for that and i is very helpful, but the one thing thats still confusing me is where you say:
"the diff pinion is already offset to the direction of the longer axle by 30mm" if it is offset to that side then wouldnt this make the 'longer' side the shorter side? if that makes sense to you

[Sam-Q]

well that's what you would think but not the case due to the shape of the diff center, I wish I had a picture of one

[drift kid]

ohkay, well i thinkkkkkk that ive gotten my head arround it, do you think that a 28spline diff would handle a 200-250kw SR20det?

[Sam-Q]

I don't see why not, those axles are damn huge. Heavy diff though

[ke70+ae92]

just a question on the handbrake, as the handbrake is crap in he r31 has anyone tryed to adapt a rear brake setup on the r31 diff with a convensional type of handbrake inside the rotor like maybe a commo setup

[Sam-Q]

I have made a dual VS Holder caliper bracket once, one for normal brakes one for the hyraulic handbrake- does that count?

[matt99]

ohkay, well i thinkkkkkk that ive gotten my head arround it, do you think that a 28spline diff would handle a 200-250kw SR20det?

I snap axles everynow and then with my 165rwkw SR86, that being said, I am still using a R31 diff with my new 250kw 86 as well, should be fine, I give them a bit of a thrashing. Mind you, I havnt broken one in a while (touch wood).

This is the reason that I have not shortened my diff the way SamQ has said, the cost of a shortened and resplined axle every time I broke one isnt worth it. Hence, im using two passenger side axles in my diff (drivers side shortened to suit) so yes, my diff is off-center, its no big deal.

The guy asking about the brakes, its a lot easier to convert to a twin caliper rear set up and use two sets of VS commy rear calipers, one on a dedicated hydro handbrake.

[Sam-Q]

I guess that begs the question how critical is the tailshaft angle really?

I am amazed you can break those axles though, do you have a race clutch or something?

[matt99]

Hope, just a heavy duty, organic plated exceedy.

My tailshaft angles hasnt seemed to have stuffed my uni's yet. Its loving life, haha.

[Skylar]

Man, stop putting stock axles back in and get strong ones made. My machinist says he can make a 28 spline axle to hold 1500hp in a drag car and run 7's.
Isn't it worth spending a little extra for peace of mind?

[matt99]

Man, stop putting stock axles back in and get strong ones made. My machinist says he can make a 28 spline axle to hold 1500hp in a drag car and run 7's.
Isn't it worth spending a little extra for peace of mind?

He say's that or he's DONE that?

Its not too hard to change an axle, so it depends how much it costs to get some axles spun up? He got a price?

[Skylar]

He's DONE that. Phil's skyline never made it to a 7 but ran 8.02 or something with enough trap to crack a 7 he says. Dyno said like 1350hp but they calc'ed closer to 1500 moroso-hp. Another car that his axles are in has gone 7.78.

I never asked about a price for his live-axle stuff but a pair of shafts to suit front of a WRX/STi were 600.

You want his details?

[Sam-Q]

so $300 for a wrx axle? sound pretty cheap to me. Getting that diff to do a 8 flat in a skyline is amazing, I commend him

[drift kid]

so samQ what diff would you recommend then? :/ as the R31 diff is so heavy and hard to make the brakes work well swell as well as find a LSD's for it, is there a better and similar cost effective diff in your opinion for a 200kw+ Sr20det powered hachi? cause im at a loss of ideas now

[Sam-Q]

if it's for drifting it's fine, cheap and easy. Handbrake sucks so bad though.

[matt99]

He's DONE that. Phil's skyline never made it to a 7 but ran 8.02 or something with enough trap to crack a 7 he says. Dyno said like 1350hp but they calc'ed closer to 1500 moroso-hp. Another car that his axles are in has gone 7.78.

I never asked about a price for his live-axle stuff but a pair of shafts to suit front of a WRX/STi were 600.

You want his details?

Sounds good. I have a machinist here that can do it, but ill grab his details anyway if you want to PM them to me ad ill grab a price off him.

[lolwat]

Or dont run duek caliper just use vs calipers and have a latch on your hydro, there isnt going to be a light stronge cheap diff solution

[Skylar]

The machinist told me a story.

A guy I know, rally guy, goes around the country and stuff competing, went to 'the best' machinist mob in Melbourne and got some axles made for the WRX because the stock ones wouldn't cut it. "Yeah, no prob, we'll make some up and they'll last", blah blah. shit didn't last. Then he tried a another mob in Adelaide, same shit, axles broke. The machinist went up to him and offered him some axles and the rally guy said bullshit, your axles are gonna snap, I tried the best places already, how are you going to do any better? Machinist offered the axles to rally guy for material cost and they haven't broken in 8 (at last count) rallies.

Along with that car and the 2 other 7 sec cars, I wouldn't trust anyone else for axles.

I'll send you a PM in a sec.

[ke_70]

im going off topic i know but if these so called axels were put into a t series i wonder how they would put up?

[Skylar]

Axles would probably rule, but the crownwheel and pinions would start to break.

Driftworks use to sell a "t-series" upgrade that consisted of spool that took 30 spline axles but the weakness of the 6.7" final drive still remained, so drivetrain issues still remain, just shifted to the next weakest thing.

[lolwat]

T series TRD 2 way, 92kw small port
http://www.ae86drivingclub.com.au/dcimages/521274.jpg

[70rolla]

92kdubbs bum bow not hating

[Sprinter Freak]

Digging this thread up, does anyone know if 13" wheels fit over r31 rear brakes?