LSD

[TheDan]

Hey all,

I have decided over the winter I am going to get an LSD installed and I don't know much about setting backlash or whatnot so will get it done professionally.

Does anyone know anywhere that does this for a reasonable price? Or have recent experience of getting an LSD installed?

I have been quoted £1760 by Birds Auto (including the Quaife LSD) and I thought that was a bit steep. I am also open to using a different brand other than Quaife if anyone has had good experiences with one.

 

[Ed Doe]

Looks like as with most stuff, the Birds Quaife pricing has gone up in recent years. I went with Birds/Quaife for my old 3.0si coupe - I think mine was somewhere around £1200-ish at the time (~2016ish), as I managed to get a group buy discount going on here. FWIW with Birds & Quaife unit you get a lifetime warranty...

I believe MFactory do a similar ATB Differential to the Quaife unit for a bit less money. I believe it's basically a copy of the Quaife unit but don't quote me on that!

Aside from that in terms of ATB differentials, there's also Wavetrac but they're more expensive than Quaife - supposedly they're a bit better (the way Automatic Torque Biasing Differentials work requires there to be some load on both wheels to 'bias' the torque to the wheel with more grip. Wavetrac supposedly has some sort of mechanism which provides drive in situations where there is no load on one wheel), but I'm not entirely convinced you'd notice it really.

ATB diffs are fit and forget - by far the easiest/cheapest type of diff to live with. If you want a more track/motorsport oriented diff look at the likes of Gripper, but expect them to be more money, a lot more aggressive and less 'road-friendly' and need more maintenance....

 

[TheDan]

Thanks for the awesome reply Ed

I am pretty certain Quaife is the right LSD for me after reading your comments. I also like that Birds offer a lifetime warranty on the Quaife units. I was just hoping not to have to pay circa £800 labour for what should be a 2-3 hour job for an experienced fitter.

Btw, I will be getting the LSD put into a 3.46 or 3.64 FD diff as the standard 3.0i manual one is 3.07 and I want shorter gears. This will make the fitter's job easier as I'll travel there with a 3.46 in the boot and travel back with the 3.07 in the boot

 

[Ed Doe]

Thanks for the awesome reply Ed

I am pretty certain Quaife is the right LSD for me after reading your comments. I also like that Birds offer a lifetime warranty on the Quaife units. I was just hoping not to have to pay circa £800 labour for what should be a 2-3 hour job for an experienced fitter.

Btw, I will be getting the LSD put into a 3.46 or 3.64 FD diff as the standard 3.0i manual one is 3.07 and I want shorter gears. This will make the fitter's job easier as I'll travel there with a 3.46 in the boot and travel back with the 3.07 in the boot

Pleasure - glad to have helped

I reckon the Quaife had to be one of the best mods I made to the 3.0si - I found it really improved my confidence in the car - it felt a lot more predictable if that makes any sense. Oh and it'll be a hoot in the snow

Nice plan on shortening the final drive - if it's anything like the same reduction between the normal ratio and 4.1FD on an M, then it'll feel noticeably punchier - enjoy!

 

[TheDan]

I have found that a place called M Style also do the 3.46 Quaife LSD for £1230 fitted, which seems a very good price.

Anyone used them before for LSD install or other work? How do they rate?

 

[Toppy]

I feel your pain Dan...I have placed an order today for an LSD, and all the options were more expensive than expected.

Given I'm going to race mine I was keen on a plated diff, but got some other prices back as well - I was quoted £1060 + VAT for a Wavetrac plus another £550 to build including new seals and bearings - that's a similar style to the Quaife.

I ended up going for a Drexler unit with a 3.73 ratio, and am no longer able to afford food for the next month or 2

 

[The.Analyst]

FWIW I understand broadly there are two sets of diffs used by BMW..a baby one with various ratios and can be easily updated to use a Quaife..the other set has the crow wheel welded on so requires some pretty precise machining prior to fitment…that may explain the pricing?

 

[Scooba_Steve]

FWIW I understand broadly there are two sets of diffs used by BMW..a baby one with various ratios and can be easily updated to use a Quaife..the other set has the crow wheel welded on so requires some pretty precise machining prior to fitment…that may explain the pricing?

Wasn't an issue for the E85/6.

 

[Ed Doe]

FWIW I understand broadly there are two sets of diffs used by BMW..a baby one with various ratios and can be easily updated to use a Quaife..the other set has the crow wheel welded on so requires some pretty precise machining prior to fitment…that may explain the pricing?

Wasn't an issue for the E85/6.

Yep this, it was only on the e89 they moved away from bolted crownwheels.

 

[The.Analyst]

FWIW I understand broadly there are two sets of diffs used by BMW..a baby one with various ratios and can be easily updated to use a Quaife..the other set has the crow wheel welded on so requires some pretty precise machining prior to fitment…that may explain the pricing?

Wasn't an issue for the E85/6.

Yep this, it was only on the e89 they moved away from bolted crownwheels.

You live and learn, thanks

 

[Scooba_Steve]

You live and learn, thanks

 

[WouterZZZZ]

Please, could you inform me about the advantages of installing a Quaife LSD during cruising at higher speed on the highway and not on cirquits? What may I expect from it? I am really interested! Friendly greetings from The Netherlands

 

[lkhc123]

Won’t notice much driving in a straight line tbh apart from the power is transferred much better than an open diff. You’ll notice it much more in the corners my friend!

 

[TheDan]

Thanks for the info guys.

I would feel reasonably confidence getting the diff out and doing all the spannering necessary for the re-installation. What I am not confident in is measuring and applying the correct backlash settings. (To be honest I am not massively keen on getting under the car and dropping the diff when its on axle stands on my not particularly flat gravel driveway either!)

I'll give Birds a bell to get their best price and M Style to try to get an idea for how competent they might be.

 

[lkhc123]

Thanks for the info guys.

I would feel reasonably confidence getting the diff out and doing all the spannering necessary for the re-installation. What I am not confident in is measuring and applying the correct backlash settings. (To be honest I am not massively keen on getting under the car and dropping the diff when its on axle stands on my not particularly flat gravel driveway either!)

I'll give Birds a bell to get their best price and M Style to try to get an idea for how competent they might be.

Whatever your decision Dan you won’t be disappointed let us know when you get it installed…

 

[Ed Doe]

as above - it's a cracking mod, get the best price you can and get it done

 

[Andres]

Hi there, I installed a Quaife diff on my own with some help from a garage as I didn't have some tools.
It took me couple days to fit on the street on axle stands, not very complicated, just time consuming, took my time to torque everything and make sure it's fitted right
I tried buying the diff from Mstyle, but they didn't seem very interested in talking to me so my advice is if you can afford it-buy it from Birds garage with fitting or if you like a challenge-do it yourself.
If you need more info about fitting it, I'm always happy to help.

 

[iiNNeX]

I would personally go with Birds unless you are confident in doing it yourself. I guess it depends on if you are willing to travel, there are quite a few good specialists around. RBM in Hook, BMR in Surrey, Redish ect. ect.

I read some horror stories with M-style on another BMW forum (not diff related), a few minutes of googling will get you the answers as to why that is.

Just my 2p

 

[Darryl_1983]

I've been considering getting a LSD for mine since buying it earlier this year. Mine is a 2004 3.0i, but I'm not prepared to spend the money required to get Birds to fit a Quaife as it's basically half the value of the car.

I'm considering the Blackline though, that is £540 for the part alone from Matt Lewis Racing (or £600 on eBay), from my searching online it seems to be a very close copy of the Quaife LSD. There are only a few threads on the forum that mention this LSD though, but the brand itself seems to be used quite a lot in other car brands, as a cheaper alternative to Quaife and I've not seen any bad feedback yet.

Be interested in knowing if there were any others on the forum with this LSD installed to there Z4's.

 

[TheDan]

I don't personally know much about them (and in the end went Quaife installed by Birds), but there was a post here (https://z4-forum.com/forum/viewtopic.php?p=1805719#p1805719) which showed the Blackline 188K in more detail.

This post was one of the reasons I DIDN'T go for it as I didn't like the design that caused the "breakthrough" machining on the LSD casing. I also wasn't keen on the quality of the edges of this machining. However, this doesn't necessarily mean that the Blackline LSD would break during use or work any worse than the Quaife. As you said, Blackline have been supplying these LSDs for a while and I haven't seen any horror stories about them breaking.

The main reason I went Birds is because I got lifetime warranty on the Quaife unit and a 24 month Birds warranty on the work carried out and I wasn't familiar enough with backlash adjustment to fit one myself.

Sorry for the waffle, but hope it helps.