looking to get a new diff

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madjak
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Re: looking to get a new diff

Postby madjak » Mon Aug 31, 2015 3:48 pm

looking to get a new one that's best for skids and get sideways


A welded or spool diff is probably more suited to his requirements.
NA8: N/A 200whp | Haltech | Skunk2 Intake | S90 TB | RCP | 5 speed c/r dogbox | 4.78 diff | AST Shocks
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jko
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Re: looking to get a new diff

Postby jko » Mon Aug 31, 2015 4:45 pm

madjak wrote:
looking to get a new one that's best for skids and get sideways


A welded or spool diff is probably more suited to his requirements.


Or a KAAZ :) I am slightly leaning towards that now haha

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hks_kansei
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Re: looking to get a new diff

Postby hks_kansei » Mon Aug 31, 2015 5:06 pm

Brand names aside.

For sliding and skidding you'll likely want a clutchpack diff, which is what a KAAZ or CUsco are (and countless others)
Clutch diffs can be setup to suit what you need, both the rate of locking (how much torque it needs before it grabs) and when it locks (1way locks only under acceleration, 2 way locks under accel and decel, but is unlocked at no load cruising, 1.5 way locks under accel, and partially locks under decel)

A Torsen (of either kind) will work better than an open diff, but not as well as a clutchpacker (for this anyway)

a Viscous is something i'd only bother with if it was cheap enough to be almost free.



If money is an issue, the most cost effective is a welded diff, or a spool.
you just open up the existing diff and have the spider gears welded in place.
the diff will be locked in all situations then.

Bear in mind, a welded diff will chatter a lot during corners, puts a lot of strain onto the driveshafts (they cna break) and will also make the rear of the car want to continue straight ahead, which means the car becomes more prone to understeer (BUT, once the rear wheels lose traction like in drifting, it wont be an issue)


Basically, a clutchpack diff is the best option for what you want.
a weldy is the cheapest, but with a lot of downsides (and really, i'd very much suggest not welding it on a car that you use on public roads)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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RileyR
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Re: looking to get a new diff

Postby RileyR » Tue Sep 01, 2015 9:08 am

My t2 does quite well for sideways....

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hks_kansei
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Re: looking to get a new diff

Postby hks_kansei » Tue Sep 01, 2015 10:19 am

Torsens can certainly do it, mine does fine as well.

But in some situations torsens can act a bit funny with the whole torque shift thing.
A clutchpack won't since both wheels turn the same speed regardless of surface/grip.

Pretty sure that the clutch diffs are more able to handle abuse as well.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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StanTheMan
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Re: looking to get a new diff

Postby StanTheMan » Tue Sep 01, 2015 10:42 am

hks_kansei

I think you explained this superbly. I wish I was a better wordsmith.

My T2 does the sideways thing as well. But Ive never gone to the extreme of lifting a rear wheel off the ground on a public road.

getting to the maintenance of it.

So we know & accept the clutchpack will lock better than a Torsen as well as performing better under abusive condition. It is my impression that clutch-packs require some maintenance. Not too much but some. While Torsens are mechanical & require no maintenance?

Could you perhaps clear this up for those of us who don't know or are misinformed and perhaps considering one or the other?
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hks_kansei
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Re: looking to get a new diff

Postby hks_kansei » Tue Sep 01, 2015 1:43 pm

basically.

Because the Torsens work off gears they have pretty low wear, about all that happens is that over time the conical washer thingys in them get a bit weaker and they lose some preload, so they feel a little looser (the torque bias remains unchanged though, so they'll continue to work forever)

Clutch pack diffs, by the nature of using little clutches, wear the clutches out eventually, and need them replaced. I don't know what the usual lifetime is on them, but my understanding is that it's a long time (hundreds of thousands of km i've heard)
As they wear they just get a bit looser and looser, and need more effort to lockup.


My preference is a Torsen for my car, and well, for any road car, and it can do skids, drifting etc if you want.
But a clutch pack diff is still more suited, since it's inherently more stable (i've had my T2 make the car feel a bit funny if one wheel hits a surface change while sliding)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

madjak
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Re: looking to get a new diff

Postby madjak » Tue Sep 01, 2015 3:08 pm

I think the preference of torsen vs clutch pack depends on your driving style and usage. I'm mostly talking about motorsport here but if you prefer to throw the car into corners, cut across kerbs the clutch pack is more suited than a torsen. I find the torsen is great if you drive smoothly, but put one wheel on a kerb or into a wet patch and I find I'm losing traction all the time. The torsen is also more suited to autocross usage unless you like drifting as the clutch packs can push you into understeer. Torsens are fast but I hate that feeling of spinning a single wheel through the middle of corner, almost like your driving with an open diff 10% of the time and I know every time it does it I'm dropping time.
NA8: N/A 200whp | Haltech | Skunk2 Intake | S90 TB | RCP | 5 speed c/r dogbox | 4.78 diff | AST Shocks
Barbs L: 64.12 | S: 58.62 | Collie: 49.72

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Re: looking to get a new diff

Postby chops » Thu Sep 03, 2015 4:21 pm

I upgraded from a Torsen to an OS Giken clutch pack for motorsport use and couldn't go back. My mate has just used the same diff in his car which sees more road use then mine does and he loves it

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Re: looking to get a new diff

Postby jko » Thu Sep 03, 2015 8:21 pm

Im going to be picking up the clutch kit this week, but won't be installing it just yet.

Does anyone have any recommendations for other parts that I could replace or upgrade whilst putting in the kit?

So far, I will be getting new rear diff bushings and ordering new bearings.

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StanTheMan
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Re: looking to get a new diff

Postby StanTheMan » Thu Sep 03, 2015 9:53 pm

Sorry totally confused I just had to delete that post. Please continue with normal programming :lol:
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