johnhef

Since I'm new to the 202 world, what are the options? I don't suppose I can do what I did with my SEC and change the ratio without confusing the traction system, but this one wheel peel stuff is for the birds. What other models are interchangeable? 210, 208...220?

I remember seeing some spring block on ebay awhile back that would let an open diff work similar to a LSD when installed, anybody remember this?

MarcusF

I'd like to know a little more how this works. On a 208 speedo, the instrument cluster computer checks the wheel speed of all four wheel speed sensors. The instrument cluster receives the wheel speeds in RPM from the traction system. I'm going to guess the 202 works the same way. If the traction system is concerned with the rotational speed of each wheel, why would it care about the final drive ratio if all four wheels are still turning at the same speed?

caution wag alert: Or is it that the traction system will tell the TCU the wheel speed, and the TCU (who knows the output shaft speed, and based on that is pretty sure what the rotational speed should be) will throw a fit and do something highly undesireable (like limp home mode)?

Ausmbtech

It won't cause a problem with the traction system as it compares wheel speeds which a diff ratio change has no bearing on. The problem is that it will cause the transmission to go into limp mode because it thinks it's slipping if you do a diff ratio change.

The transmission ECU uses both rear wheel speeds then averages them out and multiplies it by the diff ratio programed to determine the transmission output speed. If the diff ratio is changed and not reprogramed then it will get a output speed it isn't expecting so it will throw a code for "implausable ratio" and lock itself in a gear until next restart.

Some tuners can change the ratio or you may be able to recode if you get the appropriate codings (not a straight forward excercise). Id probably try using a transmission ECU from the car you take the donor diff out of if you were going to try it, but expect problems.

A W208 diff is interchangable but you need to replace a few other things like rear driveshafts and the diff ratio is longer so you will loose some acceleration. There are no dirrect swaps for a shorter ratio.

Basicly the main 2 options available for LSD's is either Kleemann or Phantom grip. Both are a spring plate between spider gear types. I've also recently found that Drexler (German company, do a search) make a proper LSD for many different Mercedes models including C43's (but you would need to double check with them)

TunerPlayground

which Phantom Grip one works for the C43?

http://store.phantomgrip.com/catalog...de5e536564025f

jumph4x

Never knew of the possibility of upgrading open differentials into clutch LSD's. They claim what 60% lockup? 2-way? That is very impressive for a conversion kit.

How is the reliability on these, has anyone on here done the Phantom Grip one?

Pretty cool stuff, alas pricey.

speedybenz

I have run the phantom-grip type LSD that Kleemann sells and it worked great. Two wheel burnouts and much nicer to drive in the wet, where typically the one rear wheel wants to spin.

I did have the diff carrier shaft roll pin shear into two pieces that did cause me to lose control and total my previous C43.

But with a better piece of metal used in place of the stock roll pin the unit still works very well.

I would say go ahead and buy the unit.

Jeff

jumph4x

I'm not entirely sure I understand what the part you are referring to is, but was this accident caused by the modification to the differential?