I recently purchased a 250 that has the cup pack fitted. Whilst driving it i can't seem to feel any affect from the LSD. I have checked the gearbox numbers and it does have the correct PK4018 box, i took the shaft out and it looks identical (from what i can see) to an LSD that we had loose out on the bench. I did jack up one side at a time and spin the other wheel but i can't feel any resistance what so ever. Im starting to think it's not working at all. Any suggestions?
the lsd is torsional on these built buy quaife. the jacking one wheel up wont work in this case. its not a plated ramp style lsd. this will help you understand its operation..
I have seen that video before. I thought they were made by GKN not quaife? I would of thought if you left one wheel on the ground and span the other it should lock up, that's what I have been told by everyone, but it doesn't have any resistance.
as far as i aware the only way you could test it is with brake rollers. when one lifts on a torsen diff the diff is pretty much useless.thats when a true lsd comes in. but a torsen is more road friendly. the way they work is via resistance to each wheel. when both wheels are in contact with the road and one starts to slip the diff will transfer more load to the other wheel. hard to do when the car is stationary.could be gkn not sure now
It needs a resistance to both wheels, one more than the other to get it to lock up. you are only turning the wheels and not putting the power to the diff itself. You need to get the inside wheel to break traction slightly, you can then feel it lock and then you can boot it, i sussed this at Spa, coming out of the last corner onto the start finish straight, just flooring the throttle just spins up the inside wheel. Getting it to spin slightly gets it to lock up. The cup diff is so like a Quaife in it's build.
Hmm OK, when it locks up do you get that sensation that the car is pulling towards the apex? No matter if I'm gentle or aggressive I'm not sure i can feel any locking, ideally need another car to compare with or another person to drive mine and see how it compares. I was 3rd gear on a large round about doing around 25/30 built the power on and it just washed wide, accelerated harder and it got worse.
That sounds like a tyre problem You need to get it to slip a bit, difficult on the road most times without being a nutter.
Tyres are all fine, they are PS4s with good tread and they were nice and warm and the road was dry. I have another Megane owner lined up next week who has one with a diff so they will be able to tell me straight away if something is wrong.
if really motivated could pull px side shaft out and torch into hole, if can see a diagonal shaft across the box there's no diff but if hole is empty (if both shafts were out you'd see right through box) then diff is fitted
Done it already, you can only see the other driveshaft. We have an LSD from another box on the bench and from what i can see when the driveshaft was out it was identical. Im sure its fine and its just my driving or something, but i will find out next week.
PS4s with good tread, alignment is fine. Suspension is standard, tried with tyres warm and cold and the roads have been dry.
You should be able to feel at least something. I also have the stock cup diff, and you can definitely feel it. Mostly noticable when accelerating from a small roundabout, or a long left to right(or the otherway around) sweep under power. You can definitly notice it, big difference compared to my previous 208 GTI. If you want to be sure if it works will driving: Turn off traction control in the wet, and accelerate out of tight 2 gear corner. If it has the LSD it will spin both wheels and just go straight, if it has no LSD it will still make a turn with the inside wheel spinning. Do this in a place with some space, because you up like 1,5m beside the place you though you were going really quick, happened to me a few times when I just had the car.
