LSD - diffs not disco biscuits

JSE · Postby **JSE** » Thu Dec 28, 2006 10:11 am

Hello,

I will be turbocharging my car sometime next year and so I'm building everything up strong before I install the turbo setup - computer, LSD, exhaust etc.

My next step is to put in a LSD, however I don't know much about differentials. What would be the best LSD for a turbocharged NA6 considering the following - won't be boosted past 150rwkw, best price, strongest, to suit the MX5s great handling.

Thanks

StanTheMan · Postby **StanTheMan** » Thu Dec 28, 2006 10:45 am

MMMOOOOOOO...... COW.

but since youre asking......
I'd convert ther rear diff to a 1.8
depending on eventual HP try to get a 3.9 or 3.6 ratio

Mazspeed is real hard core & agressive. AS OPPOSED TO
Torsen Type 1 is slightly more agressive than the Torsen Type 2 ( thats how i understand it.)

all 3 are pretty hard to break.

Babalouie · Postby **Babalouie** » Thu Dec 28, 2006 11:28 am

I'm with Stan, for that sort of power the bigger 1.8 diff would be a good idea, and while torsens are great in an NA application IMHO they don't work as well with a really powerful engine with a spiky powerband.

I reckon the Mazdaspeed is the go, it's the least harsh of all of the clutch-style diffs and is aggressive enough for track driving. I've got one

mickfred · Postby **mickfred** » Thu Dec 28, 2006 11:36 am

StanTheMan wrote:MMMOOOOOOO...... COW.

but since youre asking......
I'd convert ther rear diff to a 1.8
depending on eventual HP try to get a 3.9 or 3.6 ratio

Mazspeed is real hard core & agressive. AS OPPOSED TO
Torsen Type 1 is slightly more agressive than the Torsen Type 2 ( thats how i understand it.)

all 3 are pretty hard to break.

cool.... u DO understand somthing

Sheck · Postby **Sheck** » Thu Dec 28, 2006 2:39 pm

dont worry about the ratio's, i'm running a 6 speed with 4.3 rear end and its sweet, havent tracked it yet but drifting (on track) it was good.

As for LSD def go for the 1.8 diff, and depending on what level of locking harshness go: Mazdaspeed, KAZZ - Cusco MZ?, Cusco RZ? (cant remember the order) and then ATS. And i'm not sure where the OS ginken one sits but i'd say it'd be mid to high.

Torsen (from what i reed) seems to be a little weaker in the abuse handeling. Alot of the US drifters are wrecking them then upgrading to the clutch pack ones. Plus the torsen will not lock if one of the rear wheels is unloaded ie lifts off the ground.

Dave

JSE · Postby **JSE** » Thu Dec 28, 2006 4:20 pm

I heard the KAZZ ones are very harsh. So you are saying the Mazdaspeed one is pretty soft'ish? Cause all I want is to make the rear end strong enough to handle turbo power...I'm not really into all the locking and ratio razzledazzle and I'm not fussed. The car is a daily driver in peak hour everyday so I'm looking for something soft yet powerful enough to handle enough boost (if that makes sense and doesn't contradict itself

)

Babalouie · Postby **Babalouie** » Thu Dec 28, 2006 4:32 pm

JSE wrote:I heard the KAZZ ones are very harsh. So you are saying the Mazdaspeed one is pretty soft'ish? Cause all I want is to make the rear end strong enough to handle turbo power...I'm not really into all the locking and ratio razzledazzle and I'm not fussed. The car is a daily driver in peak hour everyday so I'm looking for something soft yet powerful enough to handle enough boost (if that makes sense and doesn't contradict itself )

The Mazdaspeed 2-way is pretty good, mine just has the std preload and if I didn't tell you otherwise you'd swear it was an open diff. No noises no clunks, just the odd chirp if you power thru a u-turn.

Sheck · Postby **Sheck** » Thu Dec 28, 2006 6:17 pm

Mazdaspeed one has half the clutch disks as the rest of them so it is less harsh, brand new you may get clunking (ask babs) but if you run it in correctly and use an oil such as castrol LSX90 then it'll be silent and like babs said you wont notice its an lsd till you light up the rears doin a u-turn or something.

Otherwise a torsen center would be what you want as it'll be in the diff already, if you buy a 1.8 torsen diff

Dave

Uncle Arthur · Postby **Uncle Arthur** » Thu Dec 28, 2006 8:33 pm

I've got a rebuilt Mazdaspeed 1.6 - it is very tight, and a bit clunky at parking speeds (and HARD

off the line in the wet the other day but that may have been axle tramp), but that said it is very VERY good and the difference is huge.

I picked mine up pretty cheap off a forumite, but it did then cost me $700 to get rebuilt, including new bearings, fluid, but no lapping (the gears were all nice and clean).

I'm very happy with the result, and no matter what anyone here says about the 1.6 being weak, I managed to drive hard on an open 1.6 for 6 years and not break it, so I'm not going to do anything radically different with this new one.....

yarnmx5 · Postby **yarnmx5** » Thu Dec 28, 2006 10:07 pm

I have a brand new 1.6 Mazdaspeed LSD 1.5-way centre which is currently with mania (also where it was purchased) so they can confirm its history (or lack of). I paid $1150 and never put it my car. So anyone out there who is interested, I am after $900 firm.

Contact simone and she will be able to help you.

Cheers.

Uncle Arthur · Postby **Uncle Arthur** » Thu Dec 28, 2006 10:16 pm

Is that $900 for the centre only?

Then expect to pay up to an additional $700-$800 (Brisbane prices) including new bearings, fluid and lapping to get that sucker rebuilt into a housing.....

If someone is looking to get the above Mazdaspeed diff, it would also be beneficial to get a spare housing - that means you will have your existing diff in the car and can do the swap in an hour or so, without needing to have the car off the road.

yarnmx5 · Postby **yarnmx5** » Thu Dec 28, 2006 10:31 pm

Yeah, I think that sounds about right.

This is something I didn't realise when I bought it, but not the reason I didn't put it in. Basically I converted my engine back to standard (after going the full-on NA route) and decided that I did'nt really need it...For my skill level, I am sticking with my semi-worn viscous LSD (off an import) I have now.

Thanks

Mick93 · Postby **Mick93** » Fri Dec 29, 2006 7:05 pm

I put a 6 speed and torsen in my NA and it is the best thing I ever did I would do this before even considering turboing it. Because the gearbox is a close ratio as opposed to a 5 speed it keeps the engine constantantly on cam and it really opens up its performance. My next step is to rebuild the engine and add a promgramable ecu to it then I will decide if I turbo it. If you want my opinion spend the cash there its not cheap but you may decide not turbo ( I might not now) just with the gearbox alone you will pick heaps of performance
A turbo sounds cool, makes it fast but the reality is we live in a time of double points and Nazi Highway Patrol I think making the best package is the way to go not nessarly the bugest horsepowered cars.