i know about the LSD's and the open diffs
why is the locked diff so easy to use for the UFR and XFR?
i thought locked diffs would cause terrible under steer and ruin the day- but it seems to be the bst way in the front drivers and the weak RWD cars-why is that
and some one explain the viscous dif to me...

illepall

Looking at it from a physics standpoint its simple. Under braking all the weight is on the front wheels and they are locked togeather, so you get even engine and wheel braking on the front tires. Under accleration out of a corner most of the weight is on the outside tires and if you like curbs then all the weight may be on the outside tire. Since the wheels are locked togeather you loose no power when you lift the inside tire on a curb hopping corner. The only time you would get understeer is when you have both front tires on the tarmak and are trying to turn.

Quote from Gimpster :

The only time you would get understeer is when you have both front tires on the tarmak and are trying to turn.

So about 99% of the time then?

'GT Touring' is right, in real life if you fit a locked diff on a FWD car you get TONS of understeer so no real FWD race cars racing use a locked diff. Most FWD touring cars in reality use clutch pack or torsen diffs, providing no more than about 50% locking under max torque.

Even an open diff is better than a locked one for racing

Quote from GT Touring :

why is the locked diff so easy to use for the UFR and XFR?

Basically because LFS's LSD-diff simulation sucks badly.
(Read: No preload, which equals open diff at neutral throttle/brake.)

Vain

But turn the brake locking in clutch pack diff up and it cures the horrible corner entry oversteer you sometimes get.

But yes, locked diffs are the way with FWD, in LFS at least.

btw - I've heard of track cars running 70% locking

It think tire loading plays a big part as well. I never really noticed this until I gotmy miata, which has a lot of negitive camber and some toe out on the front. Under acceleration the car will pull tot he left as the torque from the motor loads more weight on the right tire and it does the oppisite under engine braking. In LFS when you are cornering at 100% nearly all the load is transfered to the outside tires. Since LFS seems to place to place grip as a multiple or percent based on loading nearly all the grip is also on the oursie tire. If the diff is more open you wodul spin your inside tire, and thus lose power and speed. As a result it seems to work to cancle out the understeer effect that should be there. This is only compounded by the tendancy of the FWD cars uncany ability to roll under hard cornering.

Quote from spankmeyer :

Here take this:

LMAO your search button doesn't even work lol.

Quote from Gimpster :

Under acceleration the car will pull tot he left as the torque from the motor loads more weight on the right tire and it does the oppisite under engine braking.

Did you get a used Miata ? 'cause i'd have that checked, bad transmission/engine mounts and/or
suspension bushings can sometimes do this. My old Scirocco would also do this, pull to one side
under accel and pull to the other side under braking. Everything was worned out and/or loose on
that car though...not to mention torque steer since it was fwd.

Quote from Gimpster :

In LFS when you are cornering at 100% nearly all the load is transfered to the outside tires. Since LFS seems to place to place grip as a multiple or percent based on loading nearly all the grip is also on the oursie tire. If the diff is more open you wodul spin your inside tire, and thus lose power and speed. As a result it seems to work to cancle out the understeer effect that should be there. This is only compounded by the tendancy of the FWD cars uncany ability to roll under hard cornering.

Very good point.

It may well be that weight transfer is exaggerated a bit and this would certainly account for why locked diffs work so well in LFS. If this apparent weight transfer 'bug' was fixed we would be able to use the clutch pack diff to get the fastest lap times and also the cars would not keep flipping over all the time.

Quote from Gimpster :

It think tire loading plays a big part as well. I never really noticed this until I gotmy miata, which has a lot of negitive camber and some toe out on the front. Under acceleration the car will pull tot he left as the torque from the motor loads more weight on the right tire and it does the oppisite under engine braking.

I have a Eunos Roadster (Jap version of Miata) and it does not do this at all.

I have a Eunos Roadster too, and have driven a few Mk1 and Mk3 cars (not driven a Mk2 yet), and none of them do this. In fact, and car that requires steering correction on power/lift/brakes is a bad thing - check your track rod ends

I am sure the car is out of square to some degree. The more I crawl around it to more it looks like it may be been in a wreck. The oridinal owner had set it up for the track/autocross so I am sure it need to be re-adjusted. The car still has loads of negitive camber and a bit of front toe out and rear toe in. If I ever sell my bike it is getting an overhaul. Last time it was on the lift at the autoshop I was looking at the rear toe adjustments on the lower arm and they are not alligned left to right. After the water pump is replaced (Leaking) an allignment is next on the list.