I'm currently on the search to replace my 7inch open diif for LSD. Car will be used 90% trackdays and a little road use.

Budget is a factor so trying to weigh up the pros and cons with the options I have. I read the standard LSD can be a problem in regards to being harsh but I don't really get what is meant.

Roughly £1200 to have one of these supplied and fitted into my diff
http://www.motorsport-tools.com/3j-driveline-7-ford-sierra-nxg-lsd-differential-limited-slip-diff.html


Roughly £1000 to have one of these supplied and fitted into my diff
http://shop.quaife.co.uk/caterham-de-dion-quaife-atb-helical-lsd-differential

Roughly £500 to buy a recon LSD and a set of flanged drive shafts
FORD SIERRA 4X4 REAR DRIVE SHAFTS 100MM KITCAR CATERHAM LOCOSTHAYNES

FORD SIERRA 7 INCH 3.62 LSD DIFF 100MM BOLT ON SHAFTS KIT CAR ?


Cheers
Paul

I have used both a Trans X plate LSD and a Quaife ATB. If the plate LSD is set up correctly with the right pre load and ramp angles for the weight of the car and what you are using it for they work very well, although in my opinion a little crude. I am currently using an ATB. I have to say I am very impressed, so far the car handles a dream and comes off the line in a straight line.

I think its worth considering maintenance costs into the equation as well, I don't think the Quaife ATB's require rebuilds and they come with a solid guarantee, also they don't require ramp angle adjustments

Also has anyone ever managed to break one? I've never ever heard of it happening.

I bought a second hand Freelander fit ATB from a well used Westfield Megablade and have run it on trackdays and sprints for 2 years now and it requires no attention.

Sure is looking like the ATB is the way forwards.

Just wish they came up second hand from time to time.. Been looking for a while now.

I think the ATB also runs on standard diff oil whereas the plated ones require LSD diff oil and regular draining/replacement.

I think the biggest difference is that teh ATB will never fully lock up from what I have read, whereas the plated ones will, not sure what difference this will make though. I also believe the ATB is quieter than the plated that can be a bit noise partularly at low speed and turning corners.

On eht eold ford/anglia forumas Arrow Engineering seem to be well recommended for diff building, IIRC they can source ATB and two different 3J plated diffs (driveline? budget and NXG? more expensive), tran X is the other plated with Gripper being the daddy from what I have read. Maybe worth a call. That said I was looking for an English axle diff not a sierra so may be different.

quote:

---

Originally posted by Fcck2000

Just wish they came up second hand from time to time.. Been looking for a while now.

---

Slight change now...

My mate just offered his 4x4 Sierra Cosworth LSD to me for £120. Now I really am confused as to what to do...

I guess fitting the Cosworth LSD requires just a new pair of drive shafts to allow flange fitment to the diff?

So I could be running with LSD for as little as £200. Which makes sense to me.

I'll pop this Cosworth diff in to see how it feels, at least this way I'll know how a none LSD compared to an LSD and then how they compare to a ATB if I decide to go that route.

All so confusing

The cossie 4x4 diff should be a 7" with a 3.62 ratio and the same 100mm bolt-on CV joints as the non-cossie cars

i.e. it's the same as a V6 XR4x4's diff !

Avoid the 2wd cossie stuff as its a 7.5" diff and has larger flanges, CV's, shafts and hubs.....
So if you currently have push-in shafts you'll either need to swap to bolt-on ones and matching hubs or make some hybrid shafts up

Hybrid shafts are easy to make (see numerous old threads) but can suffer from premature wear due to the mismatch of CV joints on each shaft.

The bolt-on hubs on the other hand only come with a rear disc setup as standard.

Cossie 4x4 ones use 273mm vented discs, these have longer lugs to mount the caliper on the bearing carrier.

XR4x4's and other ordinary sierra's used 253mm solid rear discs with shorter lugs to suit.

Both of these disc brake setups use the 100mm CV joints.
If you went for one of these disc brake options you'd just need to be careful about how it would affect your brake balance and master cylinder choice as the are both likely to be more powerful than you need and are normally paired with larger front calipers and discs too.....

Or i guess with a bit of fiddling you may be able to use your existing drum setup on the bolt-on hubs - but as ford never fitted this combination of parts it could take a bit of head scratching to get right.



[Edited on 18/2/2015 by mcerd1]

quote:

---

Originally posted by mcerd1
The cossie 4x4 diff should be a 7" with a 3.62 ratio and the same 100mm bolt-on CV joints as the non-cossie cars

i.e. it's the same as a V6 XR4x4's diff !

Avoid the 2wd cossie stuff as its a 7.5" diff and has larger flanges, CV's, shafts and hubs.....


So if you currently have push-in shafts you'll either need to swap to bolt-on ones and matching hubs or make some hybrid shafts up

Hybrid shafts are easy to make (see numerous old threads) but can suffer from premature wear due to the mismatch of CV joints on each shaft.

The bolt-on hubs on the other hand only come with a rear disc setup as standard. Cossie 4x4 ones use 273mm vented discs, these have longer lugs to mount the caliper on the bearing carrier. XR4x4's and other ordinary sierra's used 253mm solid rear discs with shorter lugs to suit. If you went for one of these options you'd just need to be careful about how it would affect your brake balance and master cylinder choice.....

Or i guess with a bit of fiddling you may be able to use your existing drum setup on the bolt-on hubs

---

So have you got discs on a push-in shaft setup at the moment?

If so then it's got to be a conversion - these normally use an aftermarket bracket to hold the caliper and a disc to suit.
The trouble is there are lots of kits on the market all slightly different
Some use the std sierra discs, but some use fiesta front discs or other unrelated ones.....

If you post a few pics it would make it easier to tell you what you've got....

[Edited on 18/2/2015 by mcerd1]

quote:

---

Originally posted by mcerd1
So have you got discs on a push-in shaft setup at the moment?

If so then it's got to be a conversion - these normally use an aftermarket bracket to hold the caliper and a disc to suit.
The trouble is there are lots of kits on the market all slightly different
Some use the std sierra discs, but some use fiesta front discs or other unrelated ones.....

If you post a few pics it would make it easier to tell you what you've got....

[Edited on 18/2/2015 by mcerd1]

---

I'm in favour of the 3J NXG, having owned one of these in my last 7in diff.

You can buy direct from 3J, speak with Dan Jones and he will sort out a diff to your exact requirements, I have been to see them before and they have plenty of stock of all sorts of diffs ready to be built up to spec. Not as many as quaife though mind you!!

You will need non LSD stub shafts (if your lobro, one longer than the other)

IMHO, ATB's are good, but the rear of a 7 isn't that heavy meaning the torque biasing when lifting a wheel won't alwyqs be correct. Not as good as a properly set up plate type diff where you can have the pre load set to how you want it.

John

[Edited on 18/2/15 by jwhatley]