Silvia Club of NSW

Coming from a practical point of view the difference between the torsen and a clutch is enormous. If you doddling about the car will react differently to throttle inputs but generally the torsen will do a nice job. When you're really pressing on you don't have the steer from the rear/on the throttle effect you get from a proper clutch diff and once the rear starts lighting up the torsen gets very average very quickly.

For those that haven't driven a well setup (suspensionwise) cars with both diffs the best analogy I can come up with is the difference between a manual box and auto transmission. Ig noring the whole changing gears thing you would have noticed that an auto car simply doesn't feel right, there's a dullness to the way it puts the power down and it's very obvious there's no mechanical link between engine and wheels. Basically once you've driven a tight clutch diff thats what a torsen feels like (and don't even ask about the viscous, they suck any way you look at them)

Well from a practical point of view the torsen diff is much more practical

Clutch diffs need maintanence (in theory), are noisy, you can feel the jerk when the clutch grabs...
For a racing car, yeah...

But for me it's a compromise between performance and driveability, the torsen diff is much more suitable for a daily driver/weekend racer.

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ass, grass or gas, no one rides for free

Rims, body kit, full exhaust, pod, frount mount, boost controller, clutch, suspension and possibly stereo.

Yes, they are a good compromise but the minute the car steps foot on a track you've gone too far in the direction of comfort, they just don't work well there. The handling suffers significantly and as you often get a wheel in the air they cause significant problems. They're not bad doing 7/10's up a country road, they're not much chop for anything beyond that IMO.

Even worse is an active torsen in a RWD though, they are the pinnicle of unspeakable crappiness

For general driving and the ocassional track day a clutch type diff will last for years before it needs maintenance. If you spend lots of time drifting, that is another matter. My other car had a Nissan Competition Dept clutch type fitted in 1989 and, apart from oil changes, hasn't been touched since. It did a lot of track miles between 89 and 92. I can feel that it isn't as tight as it used to be but it is still good.

Noise? When they are tight you may get an occassional bang when the clutches release, otherwise they should be no noisier than any other diff. And I've never felt a jerk when the clutch grabs.

Perhaps you're thinking of lockers diffs.

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Nature abhors a straight line

That's true for practically anything on a road car, though. A good road-setup suspension will be too soft and wallowing on the track, whereas a track-tuned suspension is going to jump around and get airborne over the potholed and cracked cart tracks we call roads in this country, as well as give your kidneys and lower back a massive pounding.

In the end, you need to decide what you're going to use your car for the overwhelming majority of the time, and tune to suit.

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Tips for being fooli sik:

Go chrome or go home
Sneezin's Pleasin'
Da flutta is bred and butta
NOS is boss
Try to be different, just like everyone else
No boost? Ya just loost

Oh OK, you forced it out of me, torsens suck. There is no tradeoff and no excuse for running a torsen diff in a RWD sportscar unless you're worried it will clash with you Louis Vitton Handbag and Chanel sunglasses.

There, I've said, no go and get real diffs you purse carrying, blouse wearing nancyboys.

and I can't believe you spelt Louis Vitton correctly, who's a nancy boy now

But yeah, it's all a compromise, people sometimes forget that our cars are not racing cars, at least mine isn't, I'm prepared to make some compromises for performance, but it still has to be streetable enough for a daily driver. Hey, at least it's not an automatic

Same goes for suspension and stuff like that...

Just something to keep in mind when modding your car, don't go to crazy unless it's a dedicated racer.

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ass, grass or gas, no one rides for free

you've convinced me. i'm borrowing yours while you don't need it
(not your purse, you can keep that)

I got a racing car, it goes brooooooooooooooooooooom!
(also makes some clanging and scraping noises)

To me having a good diff isn't a compromise in streetability, just dollars.

If you have a reasonable modification budget a good diff is a very good way to spend some money. I'll be putting one in my car as soon as I get a chance, but at the moment, since it'll cost more than 10% of the car's total cost so far, I'm waiting for a good deal on one.
On an S15 the diff is certainly something to replace before the turbo.

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The Engine Whisperer - fixer of things

What brand could be considered a good quality diff and what sort of price range would it be, is it possible to get one supplied and fitted for under $1000.

Thanks
Russ

Thing is, I just don't see the tradeoff for streetability with a clutch diff. You'll get the odd clackity clack but thats only when doing a tight turn (u turn) from a stationary position. Personally I'd say an exhaust has a much higher tradeoff (ie being geared more towards the track) than a clutch diff. A locker is a drama, a clutch diff just isn't.

Louis Vitton - it's either from buying presents when I was pimping high class escorts or from my administering international portfolio days where they are one of the biggest corporate groups in france. You guys can choose which is the reason In the end it's not exactly hard to spell

Andrew - it may be 10% of the value of the car but it would make it twice as good, stop being a tightarse

Personally I would change the diff in an S15 before I did the shocks and springs

Rusty - only secondhand. You can buy them in japan for about 1000-1100, you should be able to sneak them through customs, fitting would be about a 5-6 hour job to get it fitted/shimmed correctly. I would recommend you get this done by a good diff place as it is critical for it to work properly

trivia - a diff looks like a bomb when goping through airport x ray machines and generally makes airport staff really nervous

Related trivia - valve guides look like bullets when going through the same security

Yes, I'm in one of those moods today. Now where did I put my Louis Vitton purs...... I mean bag

Twice as good might just be too good though

It's next on the list anyway

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The Engine Whisperer - fixer of things

That is certainly my plan of attack

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Nature abhors a straight line

Its actually Vuitton but what's spelling mistakes between nancy boys anyway

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I like my rice with some dish....

-- Chris --
www.chrislow.com