Adam M

Dont know how many people will know what I am talking about, but in the process of upping the power on my car and strengthening the gearbox to cope, I replaced my front lsd on the 22B with a quaife atb.

It looks like there migth be a future option to put a quaife on the rear instead of the clutch type R180 lsd standard on the 22b which is said to contribute to the snappy tail. I am just wondering whether anyone else would bother changing this to the quaife design atb if they had the chance.

(not a fan of oversteer, but since I havent been trained in driving this car I might benefit from learning how to drive it before trying to change it).

I changed the front as I wanted it to be able to handle much mroe torque, the standard rear can probably cope but changing it wont hurt.

Any thoughts?

Andy.F

I think changing the rear to ATB will change the handling to more neutral. Most folk like the throttle controlled oversteer that is so easy with a plate diff though

Adam M

so essentially if a complete girl (like me) with a car with so much power that it will have a tendance to oversteer at every opportunity, then it might be a good idea?

I remember sdb once saying neutral was not necessarily a good thing as it made for a car that could go either way (under or over) depending on the conditions.

since rear diff isnt such a ******* to change, will consider learning how to drive on current set up, with perhaps some courses in doing so in my own car, then if its a litle ropey, switchign at a later date.

thansk andy.

Andy.F

I would agree that a neutral car at the limit may not be the best option. I suggest a few months in a RWD cossie to learn the art of power oversteer Or you could always swap centre diffs with me

JIM THEO

Personally if I was you (if I had the money) I would change first the rear with an ATB (torque sensing) diff as it provides more control progressively and transfers immediately and constantly the power from each wheel to the other.
JIM

[Edited by JIM THEO - 9/26/2002 1:02:01 PM]

ustolemyname??stevieturbo

iTrader: (1)

Will a different rear diff really make that much difference??? Would it not be better to get the car driving first, and see how it feels with the plate diff, rather than throwing money at the car, when it isnt even on the road. A good blast round a track will give you an idea of what the car is like, in relative safety, then if you decide that the car isnt to your liking, then a diff change may an option.
Obviously you have driven the car before with the std diff, what was it like then?? Spend the money and get the car driving first, then it makes the whole process of modifying more enjoyable, when you can drive it before and after, and say, yes that was worth it.

ChristianR

iTrader: (1)

how much is a quaife atb?

Adam M

stevie,

good advice.

the money has already been spent getting the car on the road, what hasnt been spent has been put aside.

I was plannign to do what you are suggesting anyway, wasnt going to put quaife in just like that, it wouldnt be worth it.

Was planning to try it with plated rear first no question.

Drove it extensively before, and you need to be very very careful in the wet or the back will snap quite suddenly, worse than in the type rs since the set up is more for dry roads. the grip level is significantly higher and so the speeds tend to be that much quicker, making it snap even faster.

Just wanted to know if people thought it was something I should consider at all, and if so, for what reasons. Certainly not just spending for the sake of it.

Christian, quaife dont make an atb for the rear of your car,k they make one for the front, its about £550, but since its the first thing to go in the gear box, it will mean stripping down your dog box completely and rebuilding, so labour will probably cost you close to that amount again.

Whats the matter, dont have your own ideas?

David_Wallis

Pot Calling the Kettle.....

MARK, PAT??

David

ChristianR

iTrader: (1)

Adam I do have my own ideas - why do you think I went for the 2.5litre engine conversion! and before you say, yes but X has also done one or whatever you usually go on about - I only found out about the other 2.5litre engines quite a while after mine!

Now back onto the subject.....

Adam M

David,

you clearly dont know your history mate, so I suggest you look it up before jumping on the take the p1ss bandwagon.

eg. do you see a reversed manifold on mine? suggested to me, but I consider each thing using my own knowledge and decide for and against. Mark has had a lot of greast ideas, which have been made cheaper by arranging to have 2 made or whatever and so it was convenient to share costs such as shipping etc. In fact my 2.5 was sent over in the same shipment as his. It works both ways, he benefitted from my purchasing my pistons when I did (although not really in the end )

Liekwise any advantageous ideas that mark may have, he puts to me. I didnt come up with them myself, such as billet valves etc. I didnt even know what air injectors were until he explained the benefits to me, then decided they suited my needs. That is different from eharing about the existence of something and then just buying it cos X says its better.

so in short , I may not be practical like yourself, but I love my theory. christian however just loves to spend money! (ps. this is all in jest, christian and I are friends (despite denying it the other day to him!))


christian,

full credit to you for getting a 2.5, but I was talking more about the ancillaries. Eg. your asking me yesterday about changing to adjustable top mounts when you dont know what they are or what they do. Coosing to get more power by buying a bigger engine is hardly rocket science.

fyi, the quaife atb is a differential. this is a central gear that allows the axles either side of it to turn at different speeds. this is useful when cornering as the inside wheel follows a shorter radius than the outside wheel, but since they are both attached to the car, they must terefore travel at different speeds, else one will have to slip relative to the ground. This is fine and has been possible for years by means of a diff. The trouble is, standard geared differentials are such that if one wheel leaves the ground due to weight distribution on heavy cornering, or simply becomes unloaded, then the force it can aplpy to the ground is reduced and it can spin. If a non limited slip differential spins one wheel, all torque is transmitted to that wheel, and none to the other.

and so lsds were created. when there is a speed difference between the two wheels greater than athreshold, the diff locks so that even if the one wheel is slipping, at least some drive can keep powering the other wheel.

There are different types of lsd such that the nature of the torque transfer is a smooth progression between the two wheels (or axles if a centre diff), or there are lsd types with a rapid lock up, such as the standard clutch type on the type r cars. this dictates the nature of the handling, and so altering the lock uop transistion can affect the cornering of the car.

It is actually much more complexs than this, and way beyond my understanding, but I hope this migth allow you to understand why I am considering a quaife atb type diff, since quaife dont make it for our cars as stated in the earlier post.

ustolemyname??stevieturbo

iTrader: (1)

Original, would be fitting 2 engines, both 2.5 with inlets pointing whatever direction you choose. Other than that, I think most things on subarus have been tried by someone. You may be one of the first people to do XXX locally, but there is nothing 'new' in it really. If someone actually produces the parts, then people have done it before.
Still good to see people over here trying 'new' things, as the subaru tuning world in the UK is very small, and mostly limited to stickers, air filters, exhausts etc etc.
If only I had loads of money...

David_Wallis

Finally he bites

Adam, I am not by any means practical... Everything I am doing, anybody could do. I try and understand some of the theory but its far too complicated to me. The easiest way is look at what a few people have done, work out the benefits and what you want to achieve and then do it.In my case, I dont really want to achieve anything. I just did it for fun, as I wasnt aware anybody had done this in the uk. Its just something to do with the car whilst the ban runs out. The only thing I now want is to get the power above 300bhp... without mega money..

I dont understand mapping engines yet... I dont know how long to pulse injectors for or what advance to run... But Ill learn.

Eitherway... I want my car finished on a budget, and when it goes bang then I'll look at a Legacy TwinTurbo engine or build a 2.5 with fancy forged (cheap) pistons and rods etc, oh and a bus sized turbo... Then go for mega power...

If I had a licence then I would throw lots of money at the car.. but as I was doing it just for track days then I cant really justify it!

David

MorayMackenzie

Adam,

Yes, go for an ATB... but try the car without first... then you can really appreciate the differences.

Moray
(Front quaife ATB installed for ~3 years now, so clearly unqualified to comment. )

ustolemyname??stevieturbo

iTrader: (1)

I think he already has the front diff, he is talking about the rear.

Andy.F

What's all the fuss about who's idea it was I thought one of the uses for this BBS was sharing ideas ? (since we don't all share a garage with Mark/Pat )
I for one have picked up some good ideas on this site I also try to share my findings and ideas here.

I would be flattered if anyone copied any of "my ideas" .........though quite frankly amazed

ps Christian - I'm not telling which turbo's i'm using ......yet !

MorayMackenzie

ustolemynameetc..,

I was refering to the rear. I know adam already has a front quaife, and I also know that he hasn't had the chance to use it yet, poor chap.


Andy F,

What fuss?

It's just that:
A) people are winding other people up.
B) I have had a quaife on my car for over three years, so i have
a good case for having first dibbs on the idea here.

Moray

[Edited by MorayMackenzie - 9/30/2002 7:31:09 PM]

Pavlo

Actually Andy, i think Mark does seem to share his house (hallway is garage) with Pat, well, lots of Pat's "stuff" anyway.

I thought Mark had a Quaife rear diff? Or maybe he didn't have a R180 rear diff, i dunno.

Why don't you try it first and see what you think, lots more power means the handling needs to be looked at a little differently anyway.

Paul

dowser

If rear is like front (eh?), then go for it

Richard

Adam M

mark has a read quaife, but i didnt get a chance to drive his car before the dreaded gudgeon pin failure.

My rear diff is an r180 and I losing this would mean having custom driveshafts made. not such a big dilemma, but the r180 is larger and hence stronger (if a bloody nightmare to get a 3.9 final drive for). The standard driveshafts on the type r are also much stronger than on the r160 diff, so I wont be changing them.

The quaife can handle more power, and since I should be running the same torque (ish) as mark, I am certain the quaife is upto the job, but not so sure of the standard lsd.

am going to do what moray suggested, and see what its like first. The standard power delivery is going to make it very snappy, and this is something I dont enjoy at all, the fact that the quaife transfer torque linearly and progressively is very attractive at the mo.

especially when you have 0 0 0 0 0 0 0 0 2 bar

Pavlo

2bar 2shmar

This time next year, we'll all be at 2bar, and you're car will still be off the road!

The mark surely has to be 3 bar now!

Paul

Andy.F

Adam

I thought you were going to be running 40 psi ? Is the 2 bar just for 'running in'
You sure your not confusing tyre pressure with manifold pressure ? This may explain why your car is so 'snappy' at the rear

Adam M

andy, you know as well as I do that you cant expect 40 psi at the boost threshold!

you are welcome to extrapolate my description up to 2.8 bar if you want, but I was talking about snap oversteer due to the power delivery when it comes in.

If it bites at the threshold, there is no way I am going to get it to 40psi, as with spinning wheels there is no load, and no load means no boost.