Searching for anyone who has installed the 650i differential cover

[Pig Farmer]

Originally Posted by Elsabor67

Sadly and thanks to our Auto Skills shop here in Stuttgart, Germany, I had to do my suspension the old fashioned way. Floor Jack and Stands. Anyways I was able to snap 2 pics the best I could of the spacer. I do plan though to go again as soon as I can so I can measure the spacer.

This is awesome. Thanks. I know it's not perfect, but I measured the close up picture to get the ratio of width to depth and knowing the OD of the mounting surface, I backed into the length. I came within 0.3mm of my measurements. Again, I know this is not perfect but it gives me some comfort that I'm not several millimeters off.

[Derk1127]

I have been interested in this mod for awhile and never knew where to source the spacer.

[Yeineken]

Any update on finding a spacer? Hoping to order the parts on Black Friday and save a little $. Think we will be able to find a spacer or something we will need machined?

[Dackelone]

Originally Posted by Yeineken

Any update on finding a spacer? Hoping to order the parts on Black Friday and save a little $. Think we will be able to find a spacer or something we will need machined?

Maybe Harold from

Originally Posted by HP Autosport

xx

can help us out. He was the one who first figured out that the 6er diff cover fits on our 1er's.

[Pig Farmer]

Originally Posted by Yeineken

Any update on finding a spacer? Hoping to order the parts on Black Friday and save a little $. Think we will be able to find a spacer or something we will need machined?

I couldn't find an off-the-shelf spacer anywhere online. I ordered a couple feet of 6061 aluminum 1-1/4" round stock off ebay. I plan on having a machine shop cut the bar into 15.5mm slices and drill a 14.5mm hole through the center of each slice. I also ordered two M14x1.5x120 bolts from ESC Tuning. One bolt is threaded the whole length and one is partially threaded like the bolt on the 135i. I just couldn't tell by the pictures if the thread was long enough on the partially threaded bolt. These bolts are actually Audi/VW OE. I'm hopeful they are grade 10.9 and not grade 8.8, otherwise there are a few other places online that carry this size in grade 10.9. I'll keep you posted.

BTW... I talked to Harold over the phone last week about this project and he suggested that I would need to have the spacer fabricated, so i don't think he carries them anymore.

[Yeineken]

Originally Posted by Pig Farmer

I couldn't find an off-the-shelf spacer anywhere online. I ordered a couple feet of 6061 aluminum 1-1/4" round stock off ebay. I plan on having a machine shop cut the bar into 15.5mm slices and drill a 14.5mm hole through the center of each slice. I also ordered two M14x1.5x120 bolts from ESC Tuning. One bolt is threaded the whole length and one is partially threaded like the bolt on the 135i. I just couldn't tell by the pictures if the thread was long enough on the partially threaded bolt. These bolts are actually Audi/VW OE. I'm hopeful they are grade 10.9 and not grade 8.8, otherwise there are a few other places online that carry this size in grade 10.9. I'll keep you posted.

BTW... I talked to Harold over the phone last week about this project and he suggested that I would need to have the spacer fabricated, so i don't think he carries them anymore.

Just to clarify when ordering. I will need the 650i Cover (duh), the Shorter Bolt (33117521292), new sealant for the cover. And manufacture my own spacer.

And complete noob question here. Why exactly do we need the spacer?

[Pig Farmer]

Originally Posted by Yeineken

Just to clarify when ordering. I will need the 650i Cover (duh), the Shorter Bolt (33117521292), new sealant for the cover. And manufacture my own spacer.

And complete noob question here. Why exactly do we need the spacer?

Yes to the items listed above. Plus you may need a M14x1.5x120 grade 10.9 bolt. Both the bolts sold by ESC Tuning in this length are grade 10.9, however the washer on the partially threaded bolt is to big to fit within the back of the differential cover. Get the fully threaded bolt: http://www.ecstuning.com/Audi-B6_A4-...ocks/ES240518/

The reason for the spacer is that when the covers are bolted to the differential, the mounting surface on the 135i cover (on right) reaches further back than the 650i cover (on left). You can see the gap under the yardstick in this picture. Without the spacer, tightening the bolt would pull the differential bushings out of the subframe.

[Yeineken]

Originally Posted by Pig Farmer

Yes to the items listed above. Plus you may need a M14x1.5x120 grade 10.9 bolt. Both the bolts sold by ESC Tuning in this length are grade 10.9, however the washer on the partially threaded bolt is to big to fit within the back of the differential cover. Get the fully threaded bolt: http://www.ecstuning.com/Audi-B6_A4-...ocks/ES240518/

The reason for the spacer is that when the covers are bolted to the differential, the mounting surface on the 135i cover (on right) reaches further back than the 650i cover (on left). You can see the gap under the yardstick in this picture. Without the spacer, tightening the bolt would pull the differential bushings out of the subframe.

Ah makes sense. Thanks for explaining. We all have to start learning somewhere I suppose lol

Did some searching and found the old thread regarding this 650i Cover. Not sure if anything from it is of use. I didn't find much that we don't already know except some pics.

Diff cover upgrade
http://www.1addicts.com/forums/showthread.php?t=393194

[andrey_gta]

Can't some one get a set of washers and simply stack them?

[Pig Farmer]

Originally Posted by andrey_gta

Can't some one get a set of washers and simply stack them?

You could probably get away with that if you can find the right size washers. It going to be a PITA stacking the washers in that confined space. Making a spacer is not impossible if you have a miter saw and a drill press. I made one today, but it took me longer than expected... about 1 1/2 hours. I had to make a couple cuts to get the saw/vice setup right and then I f-ed up and drilled the hole off center on the first clean spacer.

[Yeineken]

Originally Posted by Pig Farmer

You could probably get away with that if you can find the right size washers. It going to be a PITA stacking the washers in that confined space. Making a spacer is not impossible if you have a miter saw and a drill press. I made one today, but it took me longer than expected... about 1 1/2 hours. I had to make a couple cuts to get the saw/vice setup right and then I f-ed up and drilled the hole off center on the first clean spacer.

Looks nice! How did those bolts that weren't BMW spec workout?

[Pig Farmer]

Originally Posted by Yeineken

Looks nice! How did those bolts that weren't BMW spec workout?

This is a great question. The the 120mm bolt from ESC has a conical shaped tip so it is more like a 115mm bolt. I believe the OE bolt is 110mm with the threads running all the way out to the tip. Looking under the car, the OE bolt extends past the nut by a little over 5mm. Doing the math (110-5+15.5) suggests we need a bolt with useable threads a minimum of 120.5mm from the bolt head. I won't know for sure if the ESC bolt works until I pull the car apart, but I plan on ordering a 130mm bolt before doing the install (just in case).

Here's my attempt to sketch out the issue..

[Pig Farmer]

I found a 130mm BMW bolt that should provide a margin for error. PN 07119914854

http://www.realoem.com/bmw/showparts...31&fg=05&hl=50

I'm not sure if the bolt comes with a washer (the separate washer listed on Realoemparts is shown as being discontinued) but a washer shouldn't be to hard to source.

[Dackelone]

Originally Posted by Yeineken

Did some searching and found the old thread regarding this 650i Cover. Not sure if anything from it is of use. I didn't find much that we don't already know except some pics.

Diff cover upgrade
http://www.1addicts.com/forums/showthread.php?t=393194

^^thanks for posting this link.

[Yeineken]

Originally Posted by Pig Farmer

This is a great question. The the 120mm bolt from ESC has a conical shaped tip so it is more like a 115mm bolt. I believe the OE bolt is 110mm with the threads running all the way out to the tip. Looking under the car, the OE bolt extends past the nut by a little over 5mm. Doing the math (110-5+15.5) suggests we need a bolt with useable threads a minimum of 120.5mm from the bolt head. I won't know for sure if the ESC bolt works until I pull the car apart, but I plan on ordering a 130mm bolt before doing the install (just in case).

Here's my attempt to sketch out the issue..

Wonder if now is a great opportunity for a bushing upgrade when in the process of all this. http://www.ecstuning.com/BMW-E82-135...ade/ES1844489/

Any feedback on upgrading the bushing?

[Pig Farmer]

Originally Posted by Yeineken

Wonder if now is a great opportunity for a bushing upgrade when in the process of all this. http://www.ecstuning.com/BMW-E82-135...ade/ES1844489/

Any feedback on upgrading the bushing?

I was considering the same thing. I looked into delrin, poly, and aluminum diff bushings but the consensus seems to suggest you will have a significant increase in NVH. These M3 diff bushings may be a viable option for a dual purpose car. It looks like they are only the fronts (i.e. "Two required").

[gap]

Thanks for all of the information Pig Farmer, came at the right time for me as I was ready to order my LSD. Ordered the MFactory helical LSD, 650i cover & bolts from ECS, and the Whiteline KDT919 bushings from Amazon. Will probably be 2-3 weeks before everything gets here and is installed. Will post my impressions on the bushings after install.

[Pig Farmer]

Originally Posted by gap

Thanks for all of the information Pig Farmer, came at the right time for me as I was ready to order my LSD. Ordered the MFactory helical LSD, 650i cover & bolts from ECS, and the Whiteline KDT919 bushings from Amazon. Will probably be 2-3 weeks before everything gets here and is installed. Will post my impressions on the bushings after install.

Awesome. For added insurance, you should probably order the 130mm BMW bolt listed above (post #35). Or make sure your local BMW dealer has one in stock.

[Dackelone]

Does anyone remember what size the special thin walled wrench - that you need to undo the center driveshaft from the diff. I seem to recall you need a very thin open end wrench on it: 36mm >?

[Derk1127]

Originally Posted by Pig Farmer

I couldn't find an off-the-shelf spacer anywhere online. I ordered a couple feet of 6061 aluminum 1-1/4" round stock off ebay. I plan on having a machine shop cut the bar into 15.5mm slices and drill a 14.5mm hole through the center of each slice. I also ordered two M14x1.5x120 bolts from ESC Tuning. One bolt is threaded the whole length and one is partially threaded like the bolt on the 135i. I just couldn't tell by the pictures if the thread was long enough on the partially threaded bolt. These bolts are actually Audi/VW OE. I'm hopeful they are grade 10.9 and not grade 8.8, otherwise there are a few other places online that carry this size in grade 10.9. I'll keep you posted.

BTW... I talked to Harold over the phone last week about this project and he suggested that I would need to have the spacer fabricated, so i don't think he carries them anymore.

Is this the final dimension of the spacer you fabricated? Thanks!

[Pig Farmer]

Originally Posted by Derk1127

Is this the final dimension of the spacer you fabricated? Thanks!

I realize this thread is kind of a work in process and needs to be cleaned up with final measurements once the install is complete. The spacer I made is 1-1/4" OD, 9/16" ID and 15.5mm long. I cut the spacer from a piece of aluminum round stock (1-1/4" in diameter). If I were to do it again, I would use 1-3/8" round stock.

An alternative method would be to get a 5/8" thick piece of aluminum plate, and use a 1-1/2" hole saw to cut out a core. I tried this with a 1/8" think piece of aluminum plate and the core was just under 1-3/8" in diameter. Then drill out the center with a 9/16" bit. This would result in a spacer 5/8" or 15.875mm long. The difference between 15.5mm and 15.875mm is about the same as 4 sheets of paper. This method requires a pretty sharp hole saw, lots oil/WD-40, and a pretty beefy drill press.

[Yeineken]

Originally Posted by Pig Farmer

I realize this thread is kind of a work in process and needs to be cleaned up with final measurements once the install is complete. The spacer I made is 1-1/4" OD, 9/16" ID and 15.5mm long. I cut the spacer from a piece of aluminum round stock (1-1/4" in diameter). If I were to do it again, I would use 1-3/8" round stock.

An alternative method would be to get a 5/8" thick piece of aluminum plate, and use a 1-1/2" hole saw to cut out a core. I tried this with a 1/8" think piece of aluminum plate and the core was just under 1-3/8" in diameter. Then drill out the center with a 9/16" bit. This would result in a spacer 5/8" or 15.875mm long. The difference between 15.5mm and 15.875mm is about the same as 4 sheets of paper. This method requires a pretty sharp hole saw, lots oil/WD-40, and a pretty beefy drill press.

Updates on the install?