I want LSD!!! (and I aint trippin')

Post by **IvanAE86** » 11 Jun 2007 08:53 pm

I'd say the Dana-30 differential would probably be the cheapest way to get LSD on a 300, but there are different carriers for higher and lower ring and pinion ratios, so which one would the 300 need? Sadly, the most you can find for a dana 30 are locker diffs, which are a bit agricultural to say the least, would probably work for a driftcar though, and for a lot more cash you could get a torsen LSD. The torsen is great for a trackcar in theory, but it sucks for drifting. What a fun car it would be if it came with a clutch-type lsd from factory (got that covered with my other car though).

Post by **Carl** » 11 Jun 2007 09:06 pm

Well my XR4x4 certainly managed to lock up ok, as did my mates 325i. Although not really being a drifter or driven a car with a completely locked diff I suppose I cant really comment on how they compare. But if you wanted a car purely for drifting surely the best option would just be to weld the diff anyway. I'd want the LSD for a quick road car/track car/rally car where, as you say, drifting ability is not essential.

My girlfriends old MX5 had the torsen diff and it seemed to work ok. A couple of mates have got the nutty versions (V Spec or something) but I think they still have the torsen diff and both are very slidable (if thats a word). I've got a vid somewhere of one of them doing an autotest and there's no problem at all with it holiding a drift.

What's the difference between a locker and an LSD then? Someone enlighten me.

Post by MJ » 11 Jun 2007 09:13 pm

I'm guessing that a diff lock is either open, or locks the diff together, like a welded diff, but is controlled electronically or mechanically by the driver. Great for 4x4's where you don't want spinning wheels so you want full lockage, and then you can unlock for road use/better conditions. A limited slip diff, obviously can automatically slip a bit when needs be to give optimum grip.

Post by **foggyjames** » 12 Jun 2007 12:34 am

A locker is pretty much on/off, while an LSD is clutched, for more gradual action.

Ali makes a good point - many of the 940 '1041' lockers don't seem to work properly any more, presumably because of their age.

cheers

James

Post by **Carl** » 12 Jun 2007 07:52 am

So when does it lock/unlock? On a proper off road 4x4 they'll be a diff lock lever (or button), surely a 2/7/900 doesn't just have one of these?

Post by **jtbo** » 12 Jun 2007 01:13 pm

You can set locking when making one, usually if wheels try to spin even a litte at different speed locker just locks (so when trying to park a car it makes lot of banging as it locks and releases), there are bit different lockers, but some make loud noise when they lock others does not. I don't know english terms for them, räikkälukko and palalukko are finnish terms, lot of use, I know

First one operates bit like socket wrench and other is more agricultural and it works with hole and stick method, hard to explain when missing needed words

Then there is many limited slip types, mechanical and electromechanical, viscous coupling is maybe bit like hydraulic, but it is mechanical usually too.
Torsen is simple thing that works opposite to open diff (more power to wheel that has more grip), however it needed bit of grip to both tires so it can operate.

Isn't sierra's differential similar to 300 so that it is attached to body?

But maybe easiest option is still to get 1030 axle internals and dana 30 locker or lsd and work those into 300 series diff. At least that would not mess too much with suspension setup etc.

Post by **Chris_C** » 12 Jun 2007 04:13 pm

I'm guessing one of the words your looking for is rachet Jani! Grand descriptions though, I knew exactly what you ment!

Post by **Carl** » 12 Jun 2007 05:19 pm

Nice on Jani, that makes a bit more sense know!

Post by **volvorsport** » 12 Jun 2007 06:34 pm

the dana diff is huge with std locker , wont fit in there .

Post by **foggyjames** » 12 Jun 2007 07:03 pm

The locking mechanism is usually actuated by a centrifuge, of sorts. The 940 '1041' units lock up automatically when excessive wheelspin is detected (i.e. no locking under normal driving), but won't lock above 25mph (unless modified

)

cheers

James

Post by **IvanAE86** » 13 Jun 2007 09:14 pm

volvorsport wrote:the dana diff is huge with std locker , wont fit in there .

Which dana diff would that be? The dana 30 is the second smallest they make AFAIK, and is the same as the volvo 1030? diff, on which the 360's 1041 diff is based. Furthermore, most of the simple locker-mechanisms are situated inside the carrier, where you're planetery gears would be.

It's a shame you dont find many american cars around here, otherwise I would just pick up a jeep diff and find out for myself.

Post by **foggyjames** » 14 Jun 2007 01:45 am

I've never heard the 300 series diff referred to by the 1030/1031 and 1041 notation usually applied to the 2/7/900 series diffs. IIRC, the IRS diff for 760s and 960s is a "1065". Where have you got the reference to 1030 and 1041 in a 300 from? This is interesting. As far as I have been able to work out, the "10" notation is simply a Volvo code. A 1030, for example, is a Dana 30. A 1031 is an updated version of the same unit with a Dana 30 differential inside, and a 1041 is a locking diff unit based again around a Dana 30.

I've heard of 300 series casings needing to be modified to accept a 240's Dana 30....however if that were more a case of bearing layout, etc, and the diff unit itself is the same, there could be cheap drop-in options courtesy (for example) of the Jeep scene in the US.

cheers

James

Post by **shimon340** » 14 Jun 2007 02:54 pm

just to drop in here but I am aware volvo made locking diffs for the 300 series. never seen one but when I started mechanics my 340 loving teacher told me about them

maybe ask in volvo 300 club holland or daf club since they have access to knowledge of 300s just as they do dafs...

Post by **IvanAE86** » 14 Jun 2007 05:09 pm

From what I've gathered around the few v300 forums around the world, the v300 diff uses 1031 (or 1041? I forget) ring and pinion gears. So unless volvo had lost their minds and designed yet another type of diff, then the diff should be the same size as the 240's 1031. The 1031 is basically a dana30 with volvo's own beefier ring and pinion setup.

This is all just speculation though, cause I've never seen anybody really doing this to their v300. I have seen photo's of cut and modified v240 rear axle casings modified to fit the v300, but that's a bit over the top for me.

From what I've seen on the few pictures of v300 diffs I have, the carrier casing seems to be a tad on the short side compared to the dana 30.. but you wont know until you put the two next to eachother and compare.

Post by **volvorsport** » 14 Jun 2007 05:54 pm

having two 1041 diffs in front of me , and peeping inside james chamber - oo er , i mean diff casing with the diff in it - the 300 carrier is about half the width - so its a big ask i think .

the 300 series was made by daf before volvo , so i wouldnt be too sure on where the diff was sourced from , if they kept the same supplier relationship .

i can bring the diff to james , for some photographic evidence , at this houswarmin/pre BKV / ryan supplies the beer party at the weekend .