Z4 High Performance Finned Differential Cover

Hello,

I attached this cover to my e46; however, one of the bolts is to short to fit because of the bulging fin. Do I have to purchase a longer bolt or did I installed it incorrectly. (Bottom left bolt)

I think you need this bolt: 07119905148. It is M10X60 while the others are M10X25.

I looked at the Z4 3.0si catalog on RealOEM. It says you need 7 of M10X25 p/n 07119905147 and also lists 1 of M10X60 p/n 07119905148.

I'm assuming you bought from Turner Motorsports. Looks like their product description is wrong, where it states it is a direct bolt-on using the existing hardware.

No you did not install it wrong. You have to get a different bolt there. I recall getting at least one different bolt when I did mine years ago.
I'll trust the above link to the ETK, that's how I ordered mine.

Thanks all I got it resolved.

I've just purchased a LSD and awaiting its arrival. I plan on installing the Z4 finned diff cover, my car is a pre 03 model so i will be buying the M10x60-8.8-ZNS version of the long bolt.
However for the remaining 7 bolts will i need my pre 2003 E46 bolts (M10X25-8.8 ZN, part #07 11 9 914 114) or the equivalent Z4 bolts for models up to 09/2003 ( M10X25-10.9ZNS3 part # 07 11 9 905 147)?

The difference is right there--grade 8.8 vs. 10.9. 10.9 is stronger.

There is nothing magical about BMW bolts. You can probably find a very similar one at a hardware store.

Originally Posted by Oz Striker

I've just purchased a LSD and awaiting its arrival. I plan on installing the Z4 finned diff cover, my car is a pre 03 model so i will be buying the M10x60-8.8-ZNS version of the long bolt.
However for the remaining 7 bolts will i need my pre 2003 E46 bolts (M10X25-8.8 ZN, part #07 11 9 914 114) or the equivalent Z4 bolts for models up to 09/2003 ( M10X25-10.9ZNS3 part # 07 11 9 905 147)?

You can use the previous 7 bolts with no issues. I used it on mine for several years without ever an issue. It would be better to use the stronger bolts sure, but know of no reason its needed. The things that are most important are the torque of the bolts for the cover, a good sealing glue type gasket and new crushed washers for the drain/fill plugs.

Alex was there any noticeable difference after you installed it? Or is it more for longevity since it helps with heat?

Originally Posted by katu

Alex was there any noticeable difference after you installed it? Or is it more for longevity since it helps with heat?

I can't really say as I installed it same time as the TMS limited slip. But it's just to help with the heat from the clutch discs.
I can say though the "visual cool" factor is noticeable. Although the M3s have a finned cover you can't see that one from the rear because the muffler is in the way. But this one you can see from behind is very sporty peering out.

Originally Posted by Tritium

Thanks all I got it resolved.

How did you resolve this? Would you care to share with everyone?

Originally Posted by cak323i

How did you resolve this? Would you care to share with everyone?

I'm sure he just bought a longer bolt. This would look great on your 330zhp Charlie

Except for the cool factor of seeing those cooling fins, there's isn't a point to this on a non-LSD equipped car is there? Am I wrong in assuming that a non-LSD diff just won't generate enough heat for this to be worth it, even on a track day? I've got to replace my diff mount bushing and the cover needs to come off anyway and if there's any kind of benefit I can justify wanting it to look cool .

Originally Posted by Alex323Ci

I'm sure he just bought a longer bolt. This would look great on your 330zhp Charlie

Yeah Alex, I was thinking the same exact thing! Seriously thinking of doing this but I already have a list of mods going on at the moment.....cf engine covers, sprint booster/sport button mod, euro first aid box, and now this...

Originally Posted by Tangent_

... justify wanting it to look cool .

I don't think there are any added benefits with non-LSD diffs but you still get heat dissipation using this and because you can if you choose to do so

Originally Posted by cak323i

Yeah Alex, I was thinking the same exact thing! Seriously thinking of doing this but I already have a list of mods going on at the moment.....cf engine covers, sprint booster/sport button mod, euro first aid box, and now this...

here it is on my previous E46..even in the dark shadows you can see it peering out. when driving behind when it passes you it's even more clearly visible

here is mine. pix taken today