My car is now too powerful

[Teutonic_Tamer]

The torque is much higher at 3000 revs than it used to be (power too, torque is just power/revs).

Nearly slid off over a bridge today.  Glad it wasn't a 4WD car faffing about shuffling power about, if the back had broken away I'd be in the river.  As it was good old front drive understeer scrubbed off the speed.

You mean a 'part time' 4wd then!    Real Torsen 4wds dont do that. 

Don't know why you K04 chaps bother remapping.

Its the old old conundrum - the more you have, the more you want. 

[Teutonic_Tamer]

How much power you running through yours Hurdy??

325bhp and 382lbft

Bloody Hell!!
Will a quaife enable you to get all that power down though??
Jeez, you must slide all over the place when putting your foot down!!

Wet weather is a challenge for the right foot, but DSG is bl00dy good at letting you meter in the power. I have had wheelspin in 4th in the damp.
A Quaife is more about control around corners, than straightline speed. The Quaife will help, but even that can only do so much until the mechanical grip is overcome to both wheels.

But even in a perfectly straight line, the Quaife can help.  Even the slightest differences between left and right can be enough to induce momentary loss of traction, and the Quaife would still help then.

[Teutonic_Tamer]

The TVR Griffith had 2 engines:-

4.3ltr - 280bhp and 320lbft - 1060kg
5.0ltr - 320bhp and 320lbft - 1060kg

Is that all?    My old S4  with its 4.2 V8 had 344bhp - and you probably know how much my current V8 steed has.

So did the AJP engines go in the Griffith? 

[Teutonic_Tamer]

What exactly does a Quaife do?? I mean, where does it fit and what does it modify?

The Quaife is a Torque biasing Limited Slip Differential. Basically it distributes the power to the front wheels. Once it feels one of the wheels slipping it transfers the power to the other wheel where it can best be used.

The standard car has what is called an open differential. This will deliver power to each wheel regardless of wheel slip.

Not quite.  Your description of the way the Quaife works was near as damn it spot on.  But regarding the standard open diff, you are way off.

On a conventional open differential (weather in a front driven axle or rear driven axle) - it will always send torque to the side of least resistance.  Stop your car with one wheel on a slippery grassy verge, with the other on firm tarmac, then turn off your ESP and boot it.  The speedo will merrily rise, but the car will remain stationary.

[Teutonic_Tamer]

What exactly does a Quaife do?? I mean, where does it fit and what does it modify?

The Quaife is a Torque biasing Limited Slip Differential. Basically it distributes the power to the front wheels. Once it feels one of the wheels slipping it transfers the power to the other wheel where it can best be used.

The standard car has what is called an open differential. This will deliver power to each wheel regardless of wheel slip.

Hurdy.. I thought it was where it delivers power to the wheel that is loosing grip. e.g the front right wheel when going round a left hand bend.

Yup, Hurdy got that slightly wrong  , but you nailed it with that one. 

Where as the normal esp sends power to the wheel with most grip?? 

Now you got that bit confused! 

I reckon you mean the EDL - or 'Electronic Differential Lock'.  This EDL is just one additional function of the ABS/ESP system, and counteracts the inherent weakness of the conventional open diff.  When one wheel on a driven axle (on the GTI, only the front, and on the R32 - also only the front - work that one out  ) rotates faster than the opposite wheel on the same axle (due to said wheel having lost traction) - then the EDL applies the brake to just the one spinning wheel - which has the effect of transferring torque back across the axle to the wheel which still has the grip.  But if you press your ESP button, you actually turn off all 'traction aids', including EDL and ASR. 

Nerd-mode over. 

[Teutonic_Tamer]

What exactly does a Quaife do?? I mean, where does it fit and what does it modify?

The Quaife is a Torque biasing Limited Slip Differential. Basically it distributes the power to the front wheels. Once it feels one of the wheels slipping it transfers the power to the other wheel where it can best be used.

The standard car has what is called an open differential. This will deliver power to each wheel regardless of wheel slip.

Hurdy.. I thought it was where it delivers power to the wheel that is loosing grip. e.g the front right wheel when going round a left hand bend. Where as the normal esp sends power to the wheel with most grip?? 

ESP (electronic stability programme) works differently. It individually brakes a wheel/s to bring the car back into line when it detects instability.

But that is specifically referring to the 'stability' function of the ESP.  It does that weather you are on the throttle or off it, braking or cornering.  But the Quaife is a device which ONLY works under accelerative traction.

The Quaife works instantly as it is mechanical and distributes more power to the wheel with the most grip and reducing it to the one that has less grip, utilising the power better and at the same time eliminating instances where the ESP or traction control would have normally cut in. AS ESP and Traction control don't cut in as often, the engine, clutch and transmission are under less stress and the Quaife may actually improve the lifespan of the cars drivetrain.

You been reading the Quaife site again John? 

But yes, basically correct.  Though I don't entirely agree with the bit about TC not always cotting in, particularly on cars which have a more 'active' (a much earlier intervention) 'nanny' setting to their ESP.  Like Saabs! 

[Teutonic_Tamer]

So in my mind no trick diff in the world is going to make that much difference in a straight line (assuming the road surface is the same for both wheels).

A Quaife (or any other equally talented ATB diff) will (should) make a difference in the real world, in the dry and in the wet.  How many roads do you know that have genuinely identical tarmac across the entire width of the road?  Even with the smallest, insignificant difference between sides, the Quaife should have a benefit.  Weather that actual benefit can be honestly perceived through the 'Mk1 Butt Dyno' is another issue though. 

The new Focus with 300bhp FWD and a Quaife gets rave reviews in the way it handles the power, so have the Quaife adopters seen any benefits in a straight line?

But I think you will find the Focus actually needs an ATB, just like the previous Focus RS.  Their 'natural' chassis just couldnt cope with their high engine outputs, so they had to fit the Quaife in the original RS, just to gain some reasonable forward momentum.  And the chassis on the new current shaped Focus hasn't been improved over the original one - so Ford are raiding every possible parts bin to get it to work properly.

[illyun]

I was right!!! 

nearly

You got it the wrong way round 

[illyun]

So in my mind no trick diff in the world is going to make that much difference in a straight line (assuming the road surface is the same for both wheels).

The new Focus with 300bhp FWD and a Quaife gets rave reviews in the way it handles the power, so have the Quaife adopters seen any benefits in a straight line?

Definetely a huge improvement and my GTI is running 320bhp... read my earlier post in this thread 

[illyun]

Noone has still quite nailed it.. and I'm rubbish at explaining things without drawing pictures or waving my hands around , so give this a read http://www.autotech.com/quaife/differentials/diffs.htm

Thats a great link, and a great explanation.
Are these things costly??

Around £1200 fitted for a manual gearbox and £1450 for a DSG... I got mine done by VWRacing in Milton Keynes and it is the best mod I have done after the remap.  In fact, if you had it on a standard GTI/Ed30 it would also be awesome as they aren't free of wheel spin either.