Now i have many problems concerning getting an LSD for my NA VL. After a recent weekend drag racing, I'm very hooked the NA performed bloody well, beating some surprising cars, VN, VR, R32 GTS-t, HK Monaro etc. Most of these cars were quicker, but i won due to the track being 1/8th mile, and very low and consistant reatction times. How ever, single wheel burnouts are lame, and traction was nearly non existant. Now deciding i want an LSD, they are rare as rocking horse **** in the 2 pinion 25 spine NA diff. I've found some turbo LSD's but they are going for $1000 or so, mainly because of the 28 spine axles, and 4 pinion centers. So doing some research, i've discovered that R31 silhoette skylines also run the same Borg Warner 78series diffs, and are LSD, great i thought, until i discover that they too are 28 spine, makeing them a very expensive donor car. A bit more searching, and XF falcons have BW 78series diffs too. and are also 2 pinion 25 spine, and LSD is more common. So my questions bassically revolve around, making up a NA vl diff, using a variety of sources. The centres are apparently interchangeable, is it as simple as bolting in the falcon centre? but I'd like to keep my 3.45 ratios, so could i bolt my gears to the LSD centre, using my axles, and housing to make a 25 spline 2 pinion VL NA LSD ??? Or the other route would be get a silhoutte center, and v8 axles or similar, and bolt them in the housing i have now. or buy a v8 diff, and fit the silhoutte center in it.. again is this possible? Thanks for the help.. if any one knows a NA LSD, let me know will save me a heap of stuffing around.

i have heaps of experience with diffs lately owing to the fact that i ran a spool in a 25 spline diff, and ended up snapping two axles in two days. i have 235's tho. i recommend you go the 4 pinion 28spline lsd and get some new 28 spline axles. heaps stronger. also you are correct about the ford centers. i recently put my old 3.45 gearing into an xg ute. go the 3.9 or 4.11 gears from a pintara and you will get heaps better acceleration. i spent bugger all on parts and my car felt a lot better. but now ive been bitten by the turbo bug so im getting rid of my na goodluck with the diff Some original photos have not been recovered yet.

I have a 25 spline LSD in a VL, i got it built up too, the diff is called a BTR 78 Series, if you can get parts from a 78 Series diff they will fit.

Quote: Originally Posted by boostedvl i have heaps of experience with diffs lately owing to the fact that i ran a spool in a 25 spline diff, and ended up snapping two axles in two days. i have 235's tho. i recommend you go the 4 pinion 28spline lsd and get some new 28 spline axles. heaps stronger. also you are correct about the ford centers. i recently put my old 3.45 gearing into an xg ute. go the 3.9 or 4.11 gears from a pintara and you will get heaps better acceleration. i spent bugger all on parts and my car felt a lot better. but now ive been bitten by the turbo bug so im getting rid of my na goodluck with the diff So your saying a ford center (if i find an LSD) will bolt into a VL housing (if they are all the 78 series diffs), I'd probably go skyline 3.7 while i'm at it I want to get mid to low 9's on the 1/8 mile which i've been told can't be done on a non turbo vl.. i ran 10.18 as it is with wheel spin. Some original photos have not been recovered yet.

I am looking around for an LSD centre at the moment through different forums,what I am looking for is a 4 pinion LSD setup for the 78 series differential which the Falcon,VL-VS Commodores and R31 Skyline Silhouettes have,which means they can be interchanged from either make of car. Does anyone know the price and availability of these diff parts new and used and where is the best place to pick them up from,I mean like does an auto parts store sell them or only a differential specialist? Also I have heard that the VL sized axles are hard to get,I have heard they are around $500 a pair brand new,does this sound right?

i picked up a 78 series diff, with a tight lsd ,out of an xd ford from the tradingpost for $250

That diff would be a 25 spline job as found in the Fairmont Ghias and Fairlane, LTD's. They are all interchangeable Valiant's included they ran 25 spline as well. 25 Spline LSD's are easy and cheap to find, but the 28 spline LSD's are hard and expensive to find, well they are around but the outrageous prices people want for them astounds me. Go a spool if you want a cheap but unreliable double spiner.

im not ashamed to say that when it comes to running mid 9's im way out of my depth. talk to a good diff company. i imagine if your going to go that fast get a full spool.

I'm not interested in having a spooled differential as I want a differential which is going to be cheap in the long run and to not have to replace broken axle shafts,etc all the time,also I heard these spooled diffs make the car difficult to drive,particularly around my area where in town it is filled with roundabouts. I know an LSD unit up to a VS Commodore will fit which is a 28 spline unit in both V6 and V8 models,I just need the cost on the parts needed,I know I have already heard $450 NZD when paying someone else to fit an LSD centre into my differential and an extra $500 for a pair of 28 spine axle shafts (new). I just need to know the cost of the pinion gears,cones,etc for a 4 pinion 28 spline LSD unit,I am aware the ones in the NA cars are only a 2 pinion 25 spline unit.

Quote: Originally Posted by Red RB30 Jet 25 Spline LSD's are easy and cheap to find, but the 28 spline LSD's are hard and expensive to find, well they are around but the outrageous prices people want for them astounds me. Where is a good spot to look? Did many falcons come with LSD's? I'm going to the wreckers to look for some. any other sources worth while looking?

FOUND ONE! Its in an XD Fairmont Ghia. So if I buy the diff, the centres change over fairly easy? it's a 2.92:1 so i'll definatly be changing the final ratio, either 3.45 or hopefully 3.7 from a skyline. How hard is it to swap the centres around? Also the tag on the diff says "Spin Resistant Diff Use recomended oil only" thats another name for LSD in my books, who agrees?

swapping the centres is easy its the alignment of the gears thats the problem. your going to have to unbolt your ring gear/crown wheel from your open centered carrier and then put it onto the lsd center. if this has slightly different spacing to your original center then you are going to have trouble. the tolerances NEED to be right.

yep.. or crunch crunch hehe if it swaps over and lines up at least. im sure u could then get it to a diff shop to have it shimmed up perfectly etc. but i dont know alot about diffs, so if it were myself. id prolly take the parts u have sourced to a diff shop along with ur car and have them fit it for you.. or at least ask their advice. Goodluck with it man.. good to see ur goin the lsd over a locker.. not that lockers are bad. but they are an easy alternative. and illegal. Some original photos have not been recovered yet.

Quote: Originally Posted by hornet FOUND ONE! Its in an XD Fairmont Ghia. So if I buy the diff, the centres change over fairly easy? it's a 2.92:1 so i'll definatly be changing the final ratio, either 3.45 or hopefully 3.7 from a skyline. How hard is it to swap the centres around? Also the tag on the diff says "Spin Resistant Diff Use recomended oil only" thats another name for LSD in my books, who agrees? That sure is a factory 25 spline limo, and they will either have a 2.92 or 2.77 ratio unless it's from a commercial then it may have 3.5 or 3.7's. As the other guy's said the actual lapping in of the gears is a little tricky if you don't know what your doing. No harm in giveing it a go though especially since it's a second hand diff and probably cost you stuff all.

the xd diff i got had 2.77.1 , and was 28 spline $250

In the VN Commodore manual we have it mentions the LSD and non LSD centres for the Borg Warner differentials use the same gear oil in the non IRS differential whereas the IRS units in the VN's use a synthetic fluid in the V8 models whereas the V6 models use a non synthetic oil,its something to do with the special seals in the V8 unit. I don't see how lapping the gears in can be too hard,the only thing which would make it hard would be shim selection but the Max Ellery manual says to go up in small increments when shimming,say when you add a shim to one side one has to come out of the other. The pinion also can be shimmed up to give the correct tooth pattern and the car manuals such as the Gregory's and Max Ellery manuals give you a chart of tooth contact patterns.

Quote: Originally Posted by vl2boot the xd diff i got had 2.77.1 , and was 28 spline $250 All 6 cylinder X-Series Falcons had 25 spline axels including Cortinas, Valiants, etc. Only the 9-inch had 28 spline axels in passenger vechiles and 31 splines in commercials such as F100's. You are right about the price though you woud'nt pay anything more than $250 for a 25 spline lsd.

it xd 351 ,toploader,28 spline lsd....i pulled the axles and center out of it to day .......just after i cut up the huge tree branch that fell on my calais .. need new bonnet and gards ....spewin no insurance

351's run the 4 pinion 28 spline same as the turbos and 5.0l's. spewing about your calais!!!

Your right I forgot about the XD-XE 351's the 9-inch was'nt availble they too used the Borg Warner, Although I can imagine finding a genuine 351 XD-E or LTD, Fairlane diff to be quite a rareity these days most were 6 cylinders. The 6 cylinder lsd's are a dime a dozen at the wreckers.