MR2 Roadster Owners Club

The Workshop => Performance Related => Topic started by: shnazzle on May 13, 2020, 08:21

Title: Kaaz final drive
Post by: shnazzle on May 13, 2020, 08:21
Just spotted this in casual browsing. 
The price is eye-watering so count me out but a final drive ratio of 4.8.... That's gotta be tasty for b-road driving,right? Maybe not best for track, depending on the track of course, but if you don't care about top speed (which I don't) then a 4.8 ratio would lead to some hefty shifts in torque lower down right? 

https://gt4-play.co.uk/shop/kaaz-final-gear-set
Title: Re: Kaaz final drive
Post by: Nvy on May 13, 2020, 09:03
Celica 2zz tranny would be better price wise. Its almost 4.6 and you can have 0.7XX 6th gear from roadster or 1zz celica tranny. If you can do the job yourself you can do it for less than a half of the price.

Also replacing the tranny as a whole would be a lot easier than dismantling the whole thing and then fitting it.
Title: Re: Kaaz final drive
Post by: Topdownman on May 13, 2020, 09:32
I had a 4.67 put in my GT86, looks like you have found the only thing for the MR2 that is more expensive than parts for the 86!

I always liked the sound of the JDM ratios but you need to find a whole car to get that I guess!
Title: Re: Kaaz final drive
Post by: Alex Knight on May 13, 2020, 12:27
Quote from: Nvy on May 13, 2020, 09:03Celica 2zz tranny would be better price wise. Its almost 4.6 and you can have 0.7XX 6th gear from roadster or 1zz celica tranny. If you can do the job yourself you can do it for less than a half of the price.

Also replacing the tranny as a whole would be a lot easier than dismantling the whole thing and then fitting it.

I'm really, really surprised that more 1ZZ MR2s haven't swapped in a 2ZZ gearbox. Closely packed ratios, and OEM reliability for not much money.

I would have by now if I was still 1ZZ.
Title: Re: Kaaz final drive
Post by: Ardent on May 13, 2020, 12:29
Quote from: shnazzle on May 13, 2020, 08:21Just spotted this in casual browsing.
The price is eye-watering so count me out but a final drive ratio of 4.8.... That's gotta be tasty for b-road driving,right? Maybe not best for track, depending on the track of course, but if you don't care about top speed (which I don't) then a 4.8 ratio would lead to some hefty shifts in torque lower down right?

https://gt4-play.co.uk/shop/kaaz-final-gear-set
I take it the price is a typo. :o
Title: Re: Kaaz final drive
Post by: Ardent on May 13, 2020, 12:30
Quote from: Alex Knight on May 13, 2020, 12:27
Quote from: Nvy on May 13, 2020, 09:03Celica 2zz tranny would be better price wise. Its almost 4.6 and you can have 0.7XX 6th gear from roadster or 1zz celica tranny. If you can do the job yourself you can do it for less than a half of the price.

Also replacing the tranny as a whole would be a lot easier than dismantling the whole thing and then fitting it.

I'm really, really surprised that more 1ZZ MR2s haven't swapped in a 2ZZ gearbox. Closely packed ratios, and OEM reliability for not much money.

I would have by now if I was still 1ZZ.
Is it a bolt out bolt in. Or a lot fiddling about.
Title: Re: Kaaz final drive
Post by: Nvy on May 13, 2020, 12:48
Quote from: Ardent on May 13, 2020, 12:30
Quote from: Alex Knight on May 13, 2020, 12:27
Quote from: Nvy on May 13, 2020, 09:03Celica 2zz tranny would be better price wise. Its almost 4.6 and you can have 0.7XX 6th gear from roadster or 1zz celica tranny. If you can do the job yourself you can do it for less than a half of the price.

Also replacing the tranny as a whole would be a lot easier than dismantling the whole thing and then fitting it.

I'm really, really surprised that more 1ZZ MR2s haven't swapped in a 2ZZ gearbox. Closely packed ratios, and OEM reliability for not much money.

I would have by now if I was still 1ZZ.
Is it a bolt out bolt in. Or a lot fiddling about.

You can check youtube, the same mods are done when swapping 2zz. Basically selector shaft and rear blockout, oh and the LSD from your box.
Title: Re: Kaaz final drive
Post by: Ardent on May 13, 2020, 14:56
Thanks.
Title: Re: Kaaz final drive
Post by: Nvy on May 15, 2020, 10:26
Quote from: shnazzle on May 13, 2020, 08:21Just spotted this in casual browsing.
The price is eye-watering so count me out but a final drive ratio of 4.8.... That's gotta be tasty for b-road driving,right? Maybe not best for track, depending on the track of course, but if you don't care about top speed (which I don't) then a 4.8 ratio would lead to some hefty shifts in torque lower down right?

https://gt4-play.co.uk/shop/kaaz-final-gear-set

Something interesting to have a look if you havent seen it. Keiichi Tsuchiya had a 3.5 gear into his A86, it was with a ratio in between 3rd and 4th but was 5th on the gear selector. Its funny shifting I guess and takes a while get used to. Here is the video:

https://www.youtube.com/watch?v=6ke2E874fto&list=PLH0kbonh8kogmHpSxXWv2eY-3eS-OZbL6&index=129
Title: Re: Kaaz final drive
Post by: ChrisGB on May 25, 2020, 14:52
I had 4.8 in the V6 Initially. It was the perfect B road weapon with the rev limit at 7500. Went up to 4.2 for some semblance of relaxed cruising, wished I hadn't. On the other hand, the Quaife ATB diff that came with the change was absolutely sublime, seemed to find impossible amounts of traction with no negative effects on handling. All in the E153 gearbox, but short gearing for B roads is ideal whatever box you use.
Title: Re: Kaaz final drive
Post by: shnazzle on May 25, 2020, 15:27
It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen. 
Wonder what the difference would be
Title: Re: Kaaz final drive
Post by: Ardent on May 25, 2020, 15:54
Let us know. ;)
Title: Re: Kaaz final drive
Post by: shnazzle on May 25, 2020, 16:05
Quote from: Ardent on May 25, 2020, 15:54Let us know. ;)
Have you seen the price of a quaife lsd? :)
Title: Re: Kaaz final drive
Post by: Petrus on May 25, 2020, 18:20
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

I am quite happy with 5 and think 5th is as long as I want it. At 3.500 rpm I am already in illegal territory! so a bit shórter would do nicely.

As to lsd I have not found enlightening info on the various thue helical options whether called Torsen, ´helical´ or the one from Quaife.* They all work pretty much the same way and the manufacturars blurp is best taken with a bág of roadsalt. Oh and anywhichone with an additional friction plate ´clutch´ you don´t want.

The ´2B´ one in mine is not a Torsen brand but other ´helical´ nonetheless and you would not know it´s there till you should loose traction but simply don´t. And when you dó press the rubber beyond adhesion, there is no break out with wild antics the opposite way upon (over)correction, but simply a smooth slide.

This off factory equipment réally impresses me and with the weight shedding the gearing is in effect shorter anyway.

* if anyone has found well founded and water holding explanation of the differences between the various helical lsd types, I would REALLY appreciate a pointer.


Title: Re: Kaaz final drive
Post by: shnazzle on May 25, 2020, 18:27
Quote from: Petrus on May 25, 2020, 18:20
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

I am quite happy with 5 and think 5th is as long as I want it. At 3.500 rpm I am already in illegal territory! so a bit shórter would do nicely.
For anybody that travels longer distances, or even 10 miles on the motorway, the 6th is definitely nice to have. 

Especially for longer journeys we do (200+ miles) not having a 6th can be a bit wearing. 
If it's just a b-road blasting tool then definitely 5 is fine and the MR-S box would be my choice. It's a hoot
Title: Re: Kaaz final drive
Post by: Petrus on May 25, 2020, 19:36
Quote from: shnazzle on May 25, 2020, 18:27Especially for longer journeys we do (200+ miles) not having a 6th can be a bit wearing.

No doubt although for that it is basically the wrong car. It is fundamentally compromised as a Gran Touring.
However1... the relatively long wheelbase and the non too stiff OEM suspension makes it surprisingly well behaved on the highway.
However2... the 1ZZ engine is nicely flexible and the 6 box is the same as the 5 speed but with a 6th gear on top thus off factory as you ordered ;-)

Title: Re: Kaaz final drive
Post by: Nvy on May 25, 2020, 20:56
Quote from: shnazzle on May 25, 2020, 18:27
Quote from: Petrus on May 25, 2020, 18:20
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

I am quite happy with 5 and think 5th is as long as I want it. At 3.500 rpm I am already in illegal territory! so a bit shórter would do nicely.
For anybody that travels longer distances, or even 10 miles on the motorway, the 6th is definitely nice to have.

Especially for longer journeys we do (200+ miles) not having a 6th can be a bit wearing.
If it's just a b-road blasting tool then definitely 5 is fine and the MR-S box would be my choice. It's a hoot

From various sources I read on the internet it appears that our final drive is 3.9XX and 5th gear is 0.815 or something close. 2zz final is 4.5XX and the 6th gear is 0.725 so it should be the same revs at 100 km/h.

Some lame calculations below:
3k rpms 0.815 - 5th gear + 3.9XX final ~ 103 km/h
3k rpms 0.725 - 6th gear + 4.5XX final ~ 99 km/h
Title: Re: Kaaz final drive
Post by: Petrus on May 25, 2020, 21:07
Quote from: Nvy on May 25, 2020, 20:56From various sources I read on the internet it appears that our final drive is 3.9XX and 5th gear is 0.815 or something close. 2zz final is 4.5XX and the 6th gear is 0.725 so it should be the same revs at 100 km/h.

Some lame calculations below:
3k rpms 0.815 - 5th gear + 3.9XX final ~ 103 km/h
3k rpms 0.725 - 6th gear + 4.5XX final ~ 99 km/h

There are quite a few different end gears but yes thát 2ZZ box has an almost negligeble lower overall ratio than thát 1ZZ box.
The 2ZZ revving 3k higher means it shoúld have shorter gearing and it is relatively more overgeared than thát 1ZZ and box combination as a compromise for highway comfort.
Title: Re: Kaaz final drive
Post by: shnazzle on May 25, 2020, 21:12
Quote from: Petrus on May 25, 2020, 19:36
Quote from: shnazzle on May 25, 2020, 18:27Especially for longer journeys we do (200+ miles) not having a 6th can be a bit wearing.

No doubt although for that it is basically the wrong car. It is fundamentally compromised as a Gran Touring.
However1... the relatively long wheelbase and the non too stiff OEM suspension makes it surprisingly well behaved on the highway.
However2... the 1ZZ engine is nicely flexible and the 6 box is the same as the 5 speed but with a 6th gear on top thus off factory as you ordered ;-)


Not wrong car at all. That's the great thing about the MR2. It's a great daily driver, even traveling longer distances.

I find it a very easy driver long distance. Stable, good gearing (with the 6th)for good mileage,comfortable seats. Even in horrible weather. It's just so easy to drive. Subwoofer, stereo upgrade, A/C and heated seats help with that.

One could argue that if all you use it for is b-road blasting and revving through short gears, an Elise would be far more suitable.
Title: Re: Kaaz final drive
Post by: Petrus on May 25, 2020, 21:27
Quote from: shnazzle on May 25, 2020, 21:12One could argue that if all you use it for is b-road blasting and revving through short gears, an Elise would be far more suitable.

Yes, one could.
You (and I with however1; 15 cm!! longer wheelbase and more forgiving suspension) have already given the reasons why the MR2 is less uncompromisingly hard core for  that.

The European spec FL has box  you want btw.; the PFL 5 speed with an overdrive 6th ´Autobahn´ gear. Italy and Spain have long distance highways too albeit with speed limits.
Title: Re: Kaaz final drive
Post by: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.
Title: Re: Kaaz final drive
Post by: shnazzle on May 25, 2020, 22:10
Quote from: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.
Well not many cars on this forum have had more torque readily available than your old 2 so there is something to be said that. 

I remember traction issues just with the turbo and the quaife does do a better job not quite opening up entirely when one side get less traction from what I remember on the SeatCupra forum.
Is that the case?
Title: Re: Kaaz final drive
Post by: Petrus on May 25, 2020, 22:24
Quote from: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.

Viscous lsd. Is that the ´4C´?

The most common is 1B = Torsen helical.
The 2B appears to be TRD helical.
These two should be pretty much the same as the Quaife helical.
Sofar not read well founded, water holding, differences explained. The TRD and Quaife are even more alike than the Torsen A which has the worm gears differently alligned (at right angles), Torsen B has the same parallel worm gears but I cannot find what type was fitted.

The viscous is tótally different and indeed behaves differently too. The crux being that the helicals are instantly, literally directly geared, whereas the viscous coupling must first have a difference in axle speeds; the greater the differnce the greater the effect thus vv too.
Title: Re: Kaaz final drive
Post by: Ardent on May 25, 2020, 23:40
Quote from: shnazzle on May 25, 2020, 16:05
Quote from: Ardent on May 25, 2020, 15:54Let us know. ;)
Have you seen the price of a quaife lsd? :)
:)
Title: Re: Kaaz final drive
Post by: Petrus on May 25, 2020, 23:41
Heads up; Quaife type lsd for sale rather cheaply ebay 184285951772
Title: Re: Kaaz final drive
Post by: ChrisGB on May 26, 2020, 15:51
Quote from: shnazzle on May 25, 2020, 22:10
Quote from: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.
Well not many cars on this forum have had more torque readily available than your old 2 so there is something to be said that.

I remember traction issues just with the turbo and the quaife does do a better job not quite opening up entirely when one side get less traction from what I remember on the SeatCupra forum.
Is that the case?

It is difficult to describe the differences but I'll try:

With the turbo on stock LSD, the car would shuffle and kick sideways a little sometimes, as if the transfer of torque across the axle was not particularly progressive.

With the V6 and viscous diff, the car would tend to squirm a little under duress, before fully spinning up both rear wheels, at which point you where very sideways very quickly. However, the squirming gave the necessary feedback to read the onset of traction loss, so very easy to read. If you ignored what was being said though, you'd spin. Only did it once, that was when an instructor reckoned a particular section was flat in third. It wasn't, but it was fun finding out what happens when you don't take notice of the information the car is giving you.

With the V6 and Quaife, the traction level was simply higher. Situations where the turbo would have been tricky where rock solid with the Quaife and the considerable level of extra go. Even over undulating damp surfaces, the  rear just seemed to dig in. Where the other big difference showed was in the way the car came out of corners. Slow and twisty or big and fast, the Quaife seemed to behave like a torque vectoring system, consistently loading the outside wheel and making it very easy to get on the throttle early and control the turn with the power Not sideways, but optimum slip angles and predicable across all sorts of surfaces and undulations. It was the most expressive setup of any car I have ever driven. I so regret selling it now.


Quote from: Petrus on May 25, 2020, 22:24
Quote from: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.


Viscous lsd. Is that the ´4C´?

The most common is 1B = Torsen helical.
The 2B appears to be TRD helical.
These two should be pretty much the same as the Quaife helical.
Sofar not read well founded, water holding, differences explained. The TRD and Quaife are even more alike than the Torsen A which has the worm gears differently alligned (at right angles), Torsen B has the same parallel worm gears but I cannot find what type was fitted.

The viscous is tótally different and indeed behaves differently too. The crux being that the helicals are instantly, literally directly geared, whereas the viscous coupling must first have a difference in axle speeds; the greater the differnce the greater the effect thus vv too.

I don't know the code of the viscous diff, it is whatever was originally fitted to the Mk2 turbo. A differential is a complex bit of design and engineering and although I would agree with the idea that similar types of diff' work in similar ways, I would expect there to be differences in the behaviour of different designs, subtle perhaps, or maybe, specific to some parts of their operation. For me, the Quaife was a truly special bit of kit, a lot of money well spent. The electronic limited slip diff in the Jag is rubbish by comparison. Wish they did a Quaife for the XES, it'd be my first mod.
Title: Re: Kaaz final drive
Post by: shnazzle on May 26, 2020, 16:00
Quote from: ChrisGB on May 26, 2020, 15:51
Quote from: shnazzle on May 25, 2020, 22:10
Quote from: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.
Well not many cars on this forum have had more torque readily available than your old 2 so there is something to be said that.

I remember traction issues just with the turbo and the quaife does do a better job not quite opening up entirely when one side get less traction from what I remember on the SeatCupra forum.
Is that the case?

It is difficult to describe the differences but I'll try:

With the turbo on stock LSD, the car would shuffle and kick sideways a little sometimes, as if the transfer of torque across the axle was not particularly progressive.

With the V6 and viscous diff, the car would tend to squirm a little under duress, before fully spinning up both rear wheels, at which point you where very sideways very quickly. However, the squirming gave the necessary feedback to read the onset of traction loss, so very easy to read. If you ignored what was being said though, you'd spin. Only did it once, that was when an instructor reckoned a particular section was flat in third. It wasn't, but it was fun finding out what happens when you don't take notice of the information the car is giving you.

With the V6 and Quaife, the traction level was simply higher. Situations where the turbo would have been tricky where rock solid with the Quaife and the considerable level of extra go. Even over undulating damp surfaces, the  rear just seemed to dig in. Where the other big difference showed was in the way the car came out of corners. Slow and twisty or big and fast, the Quaife seemed to behave like a torque vectoring system, consistently loading the outside wheel and making it very easy to get on the throttle early and control the turn with the power Not sideways, but optimum slip angles and predicable across all sorts of surfaces and undulations. It was the most expressive setup of any car I have ever driven. I so regret selling it now.


Quote from: Petrus on May 25, 2020, 22:24
Quote from: ChrisGB on May 25, 2020, 21:42
Quote from: shnazzle on May 25, 2020, 15:27It is a tempting swap to put the 2zz gearbox in,with LSD and the longer 6th.

Would be interesting to fit a quaife to replace the stock torsen.
Wonder what the difference would be

Not too sure of the differences. The Quaife was able to deploy full throttle in 2nd in the dry on R888R as long as the clutch up was seamless. More spooky, it could also manage full throttle in the wet in 3rd sometimes on R888R. The Toyota viscous diff never managed that with wet weather full throttle relegated to use in top only. Even that was occasionally marginal.

When I had the turbo, traction was generally good, but I felt the Quaife / 2GR combo dug in noticeably  harder. Part of that could be the extra weight on the rear axle though.


Viscous lsd. Is that the ´4C´?

The most common is 1B = Torsen helical.
The 2B appears to be TRD helical.
These two should be pretty much the same as the Quaife helical.
Sofar not read well founded, water holding, differences explained. The TRD and Quaife are even more alike than the Torsen A which has the worm gears differently alligned (at right angles), Torsen B has the same parallel worm gears but I cannot find what type was fitted.

The viscous is tótally different and indeed behaves differently too. The crux being that the helicals are instantly, literally directly geared, whereas the viscous coupling must first have a difference in axle speeds; the greater the differnce the greater the effect thus vv too.

I don't know the code of the viscous diff, it is whatever was originally fitted to the Mk2 turbo. A differential is a complex bit of design and engineering and although I would agree with the idea that similar types of diff' work in similar ways, I would expect there to be differences in the behaviour of different designs, subtle perhaps, or maybe, specific to some parts of their operation. For me, the Quaife was a truly special bit of kit, a lot of money well spent. The electronic limited slip diff in the Jag is rubbish by comparison. Wish they did a Quaife for the XES, it'd be my first mod.
Thanks Chris! That's exactly what I felt with the turbo on stock gearbox. "shuffle and kick" is the perfect description. 

It's obviously something that only become obvious over a certain torque level because I've never had that in the stock MR2. Having said that, behaviour in the wet is much like that as well. It's almost like you have to blindly trust that the diff will do what it needs to do and not to compensate yourself. 
Whereas the quaife sounds more like you just need to go by what the car says. 

I'm gutted for you that the car is gone. I was too chicken to ask for a ride in it :)
Title: Re: Kaaz final drive
Post by: Petrus on May 26, 2020, 18:29
Thanks for the sharing of first hand experience!

Quote from: ChrisGB on May 26, 2020, 15:51I don't know the code of the viscous diff, it is whatever was originally fitted to the Mk2 turbo. A differential is a complex bit of design and engineering and although I would agree with the idea that similar types of diff' work in similar ways, I would expect there to be differences in the behaviour of different designs, subtle perhaps, or maybe, specific to some parts of their operation. For me, the Quaife was a truly special bit of kit, a lot of money well spent. The electronic limited slip diff in the Jag is rubbish by comparison. Wish they did a Quaife for the XES, it'd be my first mod.

The Quaife (and other parallel helical lsd) have a torque bias sytem that is both instant, progressive and ALWAYS the same, making the type predictable; it is literally hard geared.

This type of lsd can have different torque bias possibility. The manufacturer can choose to increase/decrease the angles and friction surfaces of the pinions.
The Quaife has a slightly different layout of the latter; although in a parallel direction, not equally next to eachother. This adds an extra fricion component the engineer can ´program´.
As to the cost. Yes, it seems a lot, ís a stack of hard money, but apart from doing the job there is an áweful lot of costly and time consuming precision manufacturing involved. It is a very impressive bit of trick kit.

The viscous feels very much less predictable and also changes the nature of the force distribution as it heats up.