The focus has an open diff. That means the power will go to the path of least resistance. If you want the power to go to both wheels you need a limited slip diff. I recommend the torsen T2.

 

torsen is an atb, not lsd.. but yeah id suggest a torsen. i love mine

youll still get wheelspin though just probalby not as much. the handling improvement is what i noticed most

 

What do you mean atb? I've always heard of it being an LSD.

 

It is... some people just get caught up in terminology.

ATB is an Automatic Torque Biasing diff....

Quaife even markets their ATB diff as an ATB LSD, so my response to the whole "ATB, not LSD" thing is a simple STFU. :lol:

 

Thanks for the info. I looked up open differentials and found this:

http://auto.howstuffworks.com/differential2.htm

That open differential seems like a really bad thing, especially for us here in WI. You only have as much traction as the lowest gripping front tire.. this basically means the car is one wheel drive?! I'll check out the Torsen. Is this a really expensive upgrade?

-E

 

torsen is an atb, not lsd.. but yeah id suggest a torsen. i love mine

youll still get wheelspin though just probalby not as much. the handling improvement is what i noticed most

yep samething here

 

this basically means the car is one wheel drive?!

Basically...

My 2.3 Focus's diff remains stock (open) and I rotate my car's tire from front to rear, as they are directional tires and I do not swap sides with them. Point is that the right side tires wear more than the lefts... due mostly to the open diff.

An ATB LSD would be a boon to your car's dynamics and it's capability.

:thumbup:

However, they're expensive and installing them requires some tools and measuring devices not normally found in every home garage.

 

Is this a really expensive upgrade?

yes it is.

just the diff is about 600 depending on where you get it. then it needs to be installed. if you arent very car savy, do not try to do it. your transmission has to be removed and taken apart to install it.

if you by chance live anywhere near me i could help put it in tho.

 

yea, not everyone will ahve the tools to install a diff: but i think lots of folks here do.
case of beer goes along way towards paying to get car stuff done =D

 

a torsen doesnt do all that much for you in the snow. it helps but its not a huge difference. Mostly, snow is a low to no traction situation, the torsen will only help about 20% of the time. not worth it at all whatsoever in any way for a street car. What you would want is a real limited slip.

open diffs send the same torque to both wheels so yes "both wheels pull" equally.

 

open diffs send the same torque to both wheels so yes "both wheels pull" equally.

no sir, they do not. open diffs send the power along the path of least resistance. this means the wheel with the least amount of traction will be get more of the power which equals wheel spin on ONE wheel

this is commonly known as one wheel peel

 

a torsen doesnt do all that much for you in the snow. it helps but its not a huge difference. Mostly, snow is a low to no traction situation, the torsen will only help about 20% of the time. not worth it at all whatsoever in any way for a street car. What you would want is a real limited slip.

open diffs send the same torque to both wheels so yes "both wheels pull" equally.

here we go again...

 

The T2 diff has a 2 to 1 TQ ratio

 

dont open diffs send torque equally to the wheels when they are not spinning? ie a 120hp car going 50mph and flooring it...

 

Im going to have to say no. but im not 100% sure

 

dont open diffs send torque equally to the wheels when they are not spinning? ie a 120hp car going 50mph and flooring it...

Yes, sorta sometimes.

If cruising straight and flat there will be very little difference in traction from side to side.

One thing that help dramatically (which I'm surprised no one else mentioned) are the equal length driveshafts. Many older FWD didn't have these and the one wheel peel was more common.

I've never had much of a problem leaving a two stripe burnout in any of my foci. :dunno:

 

when one wheel spins there is less torque on that wheel so the other wheel doesnt get much torque either, thats why you dont go forward. even during one tire fire an open diff is sending equal torque to both wheels.

normally i dont agree with quoting some other website but its 3am and im too tired to prove myself so ill let someone else do the talking.

this quote is kind of crappy but it will have to do for now

The open differential applies equal torque or turning power to both wheels on the drive. This torque has to be commensurate with the traction or grip that the driven surface provides. The wheels will slip and the vehicle will not move if torque is more than traction. A vehicle in a situation in which one wheel on the drive is on a surface with greater traction than the other, will be stuck, as the wheel to which the differential applies too much torque, will slip.

this one may help

Problem is, that an open differential always distributes torque equally and the slipping wheel determines the maximum of torque to be generated.

or maybe this one

If the vehicle has an open (non-limited slip) differential, the vehicle torque on each axle shaft must be equal. That is, each axle shaft delivers the same torque to each of the rear tires.

Since equal torque is delivered, the amount of torque that each axle shaft transmits is limited to the torque that can be delivered to the most litely loaded tire.

all in all, be sure you do not confuse "potential traction" with "torque output" on each wheel.

Open diffs send equal torque at all times. thats all there is to it.

 

The T2 diff has a 2 to 1 TQ ratio

2.1:1 to be exact.



Clintb if you have a problem take it to PMs please, im just trying to keep the misinformation to a minimum. No more nitpicks about terminology I promise. I also promise you that NOBODY would argue against me when i say that a clutch-type LSD would do better in the snow that a Torsen-type. If they do they need to hit google a few times and figure out how they work (rotational speed controlled vs. torque output controlled).

 

bump, illinipo has got this one down perfectly straight.

I installed a clutch-type LSD in my S10, I helped a buddy install clutch-type LSDs in the front and back of his Jeep, and I installed a Torsen T2 ATB differential in my Focus. I know the differences.

 

2.1:1 to be exact.



Clintb if you have a problem take it to PMs please, im just trying to keep the misinformation to a minimum. No more nitpicks about terminology I promise. I also promise you that NOBODY would argue against me when i say that a clutch-type LSD would do better in the snow that a Torsen-type. If they do they need to hit google a few times and figure out how they work (rotational speed controlled vs. torque output controlled).

Whoops ok

 

2.1:1 to be exact.



Clintb if you have a problem take it to PMs please, im just trying to keep the misinformation to a minimum. No more nitpicks about terminology I promise. I also promise you that NOBODY would argue against me when i say that a clutch-type LSD would do better in the snow that a Torsen-type. If they do they need to hit google a few times and figure out how they work (rotational speed controlled vs. torque output controlled).

i dont have a problem, and im not agruing against the fact tht a clutch-type diff will be better in the snow then a torsen. im glad your not going to nic pick about termimology anymore.

 

Actually both the guys above are right. EQUAL torque goes to BOTH sides until one slips, then most torque escapes through that one. Both wheels will firmly pull until that give point occurs.

 

sigh.

there is ALWAYS equal torque put out of an open diff EVEN WHEN ONE WHEEL IS SLIPPING!!

 

Uh, not in a practical, useable way to 2 wheels. If one wheel slipping as in hanging in the air, other one can be loaded slightly and will not move at all. Ever watched an on car wheel balance done? One wheel spinning against balancer, other one can have car weight on it and it will not move at all. Its' spider/axle will not be turning at all, you can't have torque output in something that does not turn. The definition of torque is a "turning force". In an engine it's measured as a turning force at flywheel. Now is the total amount of torque the same coming out of the diff in toto? Yeah, engine doesn't care whether it outputs through 1 wheel or 2, total power output will be the same, the absorption of it is what changes. Here's one for you to chew on. When both wheels pulling and have equal traction, torque output is directly applied to diff case as both spiders fight and stay in same spot. In effect same result as if you welded the spiders to make a spool. How about when one axle stops and other spins up at increased speed? Meaning one spider stopped and other one moving much faster (2X) now. In effect diff is now a transmission with a gear ratio change. Why are different gear ratios used in a transmission? To effectively modify the engine torque used to do work. Engine torque into case may be the same but gear ratio changes also CHANGE OUTPUT TORQUE. In this case since one axle turning twice as fast, torque will be lower. If you don't think so, try driving for a week in a 5 speed manual trans and taking off from a light in 5th gear every time. Better yet, a 6 speed. If torque were the same coming out of diff regardless, you should be able to do that easily.

 

Uh, not in a practical, useable way to 2 wheels. If one wheel slipping as in hanging in the air, other one can be loaded slightly and will not move at all. Ever watched an on car wheel balance done? One wheel spinning against balancer, other one can have car weight on it and it will not move at all. Its' spider/axle will not be turning at all, you can't have torque output in something that does not turn. The definition of torque is a "turning force". In an engine it's measured as a turning force at flywheel. Now is the total amount of torque the same coming out of the diff in toto? Yeah, engine doesn't care whether it outputs through 1 wheel or 2, total power output will be the same, the absorption of it is what changes. Here's one for you to chew on. When both wheels pulling and have equal traction, torque output is directly applied to diff case as both spiders fight and stay in same spot. In effect same result as if you welded the spiders to make a spool. How about when one axle stops and other spins up at increased speed? Meaning one spider stopped and other one moving much faster (2X) now. In effect diff is now a transmission with a gear ratio change. Why are different gear ratios used in a transmission? To effectively modify the engine torque used to do work. Engine torque into case may be the same but gear ratio changes also CHANGE OUTPUT TORQUE. In this case since one axle turning twice as fast, torque will be lower. If you don't think so, try driving for a week in a 5 speed manual trans and taking off from a light in 5th gear every time. Better yet, a 6 speed. If torque were the same coming out of diff regardless, you should be able to do that easily.

formatting pwns you.

thanks.