Board logo

Freelander Diff and LSD Design
2spectransmissions - 7/3/17 at 10:35 AM

Hi All

My name is Chris Hughes, I am co founder of 2Spec Transmsissions. We Design, manufacture, assemble competition transmissions and drivelines.

We are about to start the design of a plate type LSD for the Freelander differential as well as offering fitment of the LSD and reconditioning of the Freelander diff units.

Aimed predominantly at the kit car market we wanted to engage with the users of these units to see what would best suit them and get any feedback on use etc.

Is this something that the community is looking for and does the freelander CWP ratio suit peoples needs as we can look at new ratios if there is a demand?

Thank you for reading and thank you in advance for any feedback/help you can give.

Chris


Ugg10 - 7/3/17 at 11:01 AM

Most people using the freelander diff are those with bike engine. The bike engine gearboxes have a primary reduction gear built in and therefore the diff in a car has to replace the engine and rear wheel sprocket ratios (typically about 2.5:1). The Ford Sierra 3.14 and freelander 3.2 get closest so that they have a usable top end speed. Is the freelander diff casing alloy, if so that would be a bonus.

If you want to play about with diff ratios then this link allows you to put in primary and final drive -

http://www.subarugears.com/Ratios/Ratios.html

Hope this helps.

[Edited on 7/3/17 by Ugg10]


bi22le - 7/3/17 at 01:08 PM

If I was going to introduce a diff to market I would look to optimise its design, and therefore ratio to the BEC market.

I would also look at contacting the big names of the kit car market to gain support, knowledge and momentum.

Look at what 3.14 LSD goes for!

Final thought is making it a straight swap for a ford IRS diff, if that is even possible. That would target retro fitters and new builders.


CNHSS1 - 7/3/17 at 01:48 PM

A replacement diff inc case to Ford 7" dims would have legs imho, as there aren't many Sierra around to pillage bits from these days. The oem Sierra diff and case is a heavy old lump compared to freelancer so weight would be of importance.
Whilst the bike engines guys are chasing the 3.14/3.2 ratios, the competing car guys often want lower than fords oem 3.9, so have to buy aftermarket CWPS from likes of SBD at £500 + vat. 4.1, 4.4 and 4.7 are most common with the odd 5.1 but I believe the teeth are a tad small and not as strong. Certainly a cwp 4.4 at £350ish would sell I'm sure.


coyoteboy - 7/3/17 at 01:59 PM

I presume you're addressing the inherent issue with the freelander diff loading first or does this not cause a problem on kitcar vehicles? Seems to be a massive weak point on them (in the original vehicle), with them lunching diffs while used purely for motorway miles - not sure of the reasoning but the updated diff has bigger bearings and apparently there's a software patch to reduce rear diff loading?

[Edited on 7/3/17 by coyoteboy]


Doctor Derek Doctors - 7/3/17 at 08:31 PM

Offering some driveshafts as well would be a good move. To get some shafts that went from a Freeloader diff to Ford hubs for my Locost was a nightmare. I ended up tracking down the original manufacturer of the Westfield Mega blade shafts and buying up the last couple they had on the shelf.

If you don't offer driveshafts then I think you will be limiting you market as your potential customer base will then be faced with another bill for custom shafts on top of the diff. At least with the Sierra diff driveshafts can still be purchased new.


2spectransmissions - 9/3/17 at 04:28 PM

Hi All

Thank you for your replies it is much appreciated!

We have stripped and measured up the standard unit and the design is basically finished now.

We are sending the CWP off to quote so will see what we get back.

We are looking into the journal size upgrade as there are conflicting views on what it was for and if it was needed etc. The main weakness seems to have been with the centre viscus diff unit as the front and rear CWP ratios were slightly different so would cause a speed delta across the diff and eventually wear it out.

The driveshafts to suit is a great call, are they usually a set length or would they need to be custom? Not an issue if they need to be.

Thank you again for your help.

Chris


coyoteboy - 9/3/17 at 08:08 PM

Driveshafts is definitely a good call.

The diff issue wasn't with the centre diff though, there's a service bulletin on them where they rebuild or retrofit the rear diff with different bearings. My brother has just had it done and the specialist he took it to said it was a daily job for them, with LR admitting there was a fault with the design but not enforcing a recall due to cost - most people just pay up.

http://www.freel2.com/gallery/albums/userpics/11383/LTB00342.pdf

Static bearing overload in rear diff...


obfripper - 9/3/17 at 09:24 PM

The failures are with the freelander 2(and evoque,xc60 +other fords and volvos) diff pinion bearings being damaged by jerky/sudden haldex clutch engagement, and is sorted with a software update and a new diff/haldex assembly.

The freelander 1 has a completely different diff, and is far more reliable in normal use. As mentioned the usual cause of damage is a stiff/siezed centre viscous coupling causing the diff to be overloaded continually. They can also suffer the same sort of wear caused by mismatched tyres ( mix of tread depths or makes of tyre).

These problems don't exist in a kit car application, the only thing is to avoid early model diffs as they were a weaker design (iirc the cv joint carrier bearings were what commonly failed), but tbh i doubt there are many of those left that are serviceable. The current part number is TVK000180.

Dave


mcerd1 - 10/3/17 at 09:47 AM

quote:
Originally posted by obfripper
The failures are with the freelander 2(and evoque,xc60 +other fords and volvos) diff pinion bearings being damaged by jerky/sudden haldex clutch engagement, and is sorted with a software update and a new diff/haldex assembly.

The freelander 1 has a completely different diff, and is far more reliable in normal use. As mentioned the usual cause of damage is a stiff/siezed centre viscous coupling causing the diff to be overloaded continually. They can also suffer the same sort of wear caused by mismatched tyres ( mix of tread depths or makes of tyre).

These problems don't exist in a kit car application, the only thing is to avoid early model diffs as they were a weaker design (iirc the cv joint carrier bearings were what commonly failed), but tbh i doubt there are many of those left that are serviceable. The current part number is TVK000180.

Dave

^^ that he said - which freelander are we talking about here ?

I would guess most people mean the landrover original ones - rather than the ford mondeo in drag.....


coyoteboy - 10/3/17 at 12:23 PM

It is an FL2 - assumed that was sufficiently old to be using that diff, didn't consider the FL1 as an option but I guess it's actually ideal.


mcerd1 - 10/3/17 at 01:31 PM

quote:
Originally posted by coyoteboy
It is an FL2 - assumed that was sufficiently old to be using that diff, didn't consider the FL1 as an option but I guess it's actually ideal.


All the ones in kits that I'm aware of are freelander 1's

which makes sense when you see the freelander 2's diff will all the Haldex stuff on it...

FL2=


vs FL1 =


the FL2 has as much in common with the FL1 as the Austin and BMW mini's have in common with each other