Well. It's now winter time and time to put the mighty 600SL 107 down for some mods. Most needed is the LSD upgrade. The options are few. Phantom Grip or Roncallo Grip. I don't like the Phantom Grip solution as it looks to me like a band aid that just makes metal in your diff.

Last year I had delusions of grandeur, that these diffs would be just like the Chevy and Ford units I am so much accustomed to. I was hoping to luck out and swap the 140 carrier with the 107 LSD carrier. Well that isn't going to happen and the reason is obvious in the photos.

So now I'm evaluating the possibility of modifying the 140 carrier to accept clutches. So I now have both diffs apart and the job does like like a possibility with a lot of machine work.

1) The space between the side gears in the 140 is less than the space in the 107. There are two solutions to this, First shave the clutch spline down on the 107 side gears about 2.5 mm and use 1 less friction and steel. Or spot face the inside of the carrier to widen it. Or probably some combination of both. Using Kevlar lined clutches should make up for the lack of one disk.

2) The inner diameter of the 140 carried is cavernous. This leaves nothing to work with to engage the clutch steels plates. A slip in retainer must be made to do this. See the photo of the retainer I have designed, which will require machine work of the carrier to install.

3) Note to self. If I ever do this again it will be with a Ford or Chevy diff where I can get any ratio I want with or without LSD for about $100.00

4) If I pull this off I will be the Mod God.

Attached Thumbnails

     

__________________
To see my 129 parts for sale visit:
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John Roncallo

I'm intrigued,nice work!look forward to seeing the results,i need to go down this road with my W202 diff so if you get a few spare moments could you make me one too =P

Progress on the 140 diff. I have completed the evaluation on the 140 large case diff for modification into LSD. I have concluded it is possible but there are several challenges.

1) I have to make up ~ 7mm of clutch space, meaning I have 9mm to do what was done in 16mm. This can be accomplished in 2 ways. I can machine out the case to open the stack clearance up to maybe 11mm. In doing this I will be reducing axle shaft bearing area. I can also use thinner disks and steels. The stock steels are 1.1mm ~ 0.042". I can cut that down to 0.025 steel. Cutting the steel thickness in half essentially means the steel will run a 2 times the temperature and have half the strength, ouch. I can combat the temp and strength problem with the use of a super alloy Inconel 718. It has about 3 times the strength of mild steel and is used in rocket nozzles. The only problem with Inconel is the 2 sheets I need 12" x 24 of 0.025" and 12" x 12" of 0.060" cost $400 total. Hopefully I will find something in between the $30.00 of mild steel and the $400.00 for the super alloy. So the bottom line is its hard and expensive but it is doable.

2) Making and fitting the clutch drum as shown in the original post. With 0.025" almost knife edge steel tangs and double the HP of the stock 560SL, I believe this should be made of a good alloy steel like 4340 pre-hardened. Not impossible but difficult for me to machine. The Carrier will also have to be machined out to accept this clutch drum, requiring specially hand made tooling and a milling machine with a rotary table. I do not have the rotary table I need to make this at the moment. Nothing $600.00 or so wont fix.

3) The axles on the 126/107 carrier are designed to float axially with the spider gear in that there is no bearing in the side covers. The 140 carrier has ball bearings pressed onto the axles and into the side covers. In order for the limited slip feature to work the side gear cannot be restrained axially. I cannot count on the side gear spline to allow for this movement under load. therefore the bearing has to be made a slip fit which means the side covers will need to be modified with liners. The axial motion only needs to accommodate 0.020" or so but it needs to be there. I'm hoping I can get away with opening up the bore and going with some spray on treatment like a process called DLC - Diamond Like Coating or something maybe cheaper.

So in any case I have come to the conclusion that this LSD diff is going to cost in the neighborhood of $2000 between tooling and material. But I haven't given up yet. I just ordered a used 1995 SL500 diff with the same carrier and ASR sensors. I am putting my diff back together so I can have a running car while I experiment. Due to the cost I expect this to be a year long project. I will probably start out by purchasing a rotary table and fabricating and fitting 2 clutch drums probably out of plastic first. If that all works out I will see about the bearing linings and finally purchase the Inconel backed clutches and steels.

__________________
To see my 129 parts for sale visit:
http://stores.ebay.com/The-Mercedes-SL-Store
John Roncallo

Have you thought about Titanium for the clutch space??

__________________
All it takes for evil to prevail is for good men to stand by and do nothing.

Too many people tip toe through life, never attempting or doing anything great, hoping to make it safely to death... Bob Proctor

'95 S320 LWB
'87 300SDL
'04 E500 wagon 4matic

great work and well done for designing/ building a lsd, but... the halfshafts will be the week spot, they snap like carrots

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ce 320 amg
widebody
tiwn turbo
Mutty 'der nail'
soon to be a six speed nail


"some mods improve your car and make it into something it never was, other mods, however, although essentially the same, are not, and make that car a ricer"

if your car isnt shiny, you dont know what you are talking about, remember; paint shine = knowledge. In order to be taken seriously, you should spend all your money on paint, (and get a dyno reading).
Dont forget to polish it often

Ti offers no advantage for this application with the exception of maybe saving 4 oz. of weight.

__________________
To see my 129 parts for sale visit:
http://stores.ebay.com/The-Mercedes-SL-Store
John Roncallo

Halfshafts are custom made 4340 alloy steel. Indecently the 1986 560SL came with 25mm shafts and the 1996 SL600 came with 23mm shafts. I now have 4340 25mm shafts.

__________________
To see my 129 parts for sale visit:
http://stores.ebay.com/The-Mercedes-SL-Store
John Roncallo

I wonder if you wouldn't be miles ahead to use a GTO centersection ? They are very tough

__________________
There's no substitute for cubic inches

Not familiar with the GTO diff. I was considering Ford or Corvette diffs. whatever the solution a 2.65 ratio is required until I can get the transmission to run stand alone. These solutions also require re-engineering of my drive shaft and axles.

__________________
To see my 129 parts for sale visit:
http://stores.ebay.com/The-Mercedes-SL-Store
John Roncallo

I heard it has greater strength and wear resistance....

__________________
All it takes for evil to prevail is for good men to stand by and do nothing.

Too many people tip toe through life, never attempting or doing anything great, hoping to make it safely to death... Bob Proctor

'95 S320 LWB
'87 300SDL
'04 E500 wagon 4matic

Unless your wanting to embark on this clutched Mercedes diff expedition I'd like to note that Kleemann uses LSD spring blocks in their "K" series special Mercedes and they have no diff failures on record. The PG spring blocks have no failure reports either except for a few DIYers who installed it quite wrongly and shot the guide pin through the case. They are much softer than the diff and they don't wear out like the their description makes it seem. The springs will get tired but even that takes a large amount of beating on the drive-train.

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1997 Mercedes E320 Turbo
Garrett T3/60-1 Turbocharger
Custom Water Intercooler Setup
352rwhp/366rwtq @ 8.6psi in '08

http://img78.imageshack.us/img78/1051/log7smallay9.jpghttp://img66.imageshack.us/img66/740...s3smallox0.jpg

I found it thanks. Not sure if they are using this on top of ESP or are they disabling ESP for these installations. For me it has to be total stand alone.


http://www.kleemann.dk/Performance/Handling/Differential.aspx

__________________
To see my 129 parts for sale visit:
http://stores.ebay.com/The-Mercedes-SL-Store
John Roncallo

140 is the same 1.3 liter case as the 124.

You can buy a factory LSD carrier. Switch them out.. plan on a grand. - is this an ASR or non-asr setup. DaveM of Bosie has done one and has all the information on factory part numbers, etc. I think the wholesale price of the factory carrier (LSD) is about $770.


M

It's completely different. It's a 1.4 Liter case with bearings on the side covers. See one of my earlier post with the picture of the 140 and 126 carriers. The 124 is like the 126. I just about have Dave's website cloned. He has been an invaluable help. There is no LSD carrier available that will go into the 140 case.

__________________
To see my 129 parts for sale visit:
http://stores.ebay.com/The-Mercedes-SL-Store
John Roncallo

They use it on top of the ESP. With the ESP off button activated the traction control rarely interferes since the wheels spin much closer to the same speed when taking off or sliding around. My friends dad's K7 C55 AMG has no problem doing two wheels burnouts or drifting around non-stop.

__________________
1997 Mercedes E320 Turbo
Garrett T3/60-1 Turbocharger
Custom Water Intercooler Setup
352rwhp/366rwtq @ 8.6psi in '08

http://img78.imageshack.us/img78/1051/log7smallay9.jpghttp://img66.imageshack.us/img66/740...s3smallox0.jpg