M3 Lightweight Air Duct Help

[NeilM]

Also ordered all the Euro underpanels too.

Details?

Neil

[sirhodjibob]

Details?

Neil

51-71-2-491-567 - Center underbody panel
51-71-2-490-230 - Underfloor coating bracket
11-81-1-095-700 - Stop buffer for x brace
51 71 2 489 775 - "Screening" - this should attach next to center underbody panel and cover the side of the oil pan.
07-11-9-916-949, 07-12-9-904-231, 07-11-9-901-299 - nuts and bolts to install all this

The main underbody panel (51-71-2-491-567) is coming from Schmeidmann in Denmark, so this make take a minute to get here (although I've had good luck in the past).

[sirhodjibob]

Hi ,

Part #s 17-21-2-227-344 and 51-71-2-490-230 are blocked for ordering here in the US as they're only for the European market. If the vehicle has been imported and registered in the US, we can submit a copy of the registration or import documentation to BMW to have the part(s) unblocked. If not, we unfortunately won't be able to source (sorry). Please let us know at your earliest convenience.

Thank you,


Internet Parts Rockstar

Welp. Guess I'm ordering from Schmeidmann again.

[das borgen]

Welp. Guess I'm ordering from Schmeidmann again.

you can try the dealer too. They normally have no qualms getting you euro only E36 parts if you have a P/N

[sirhodjibob]

you can try the dealer too. They normally have no qualms getting you euro only E36 parts if you have a P/N

That was the email from the dealer.

[NeilM]

you can try the dealer too. They normally have no qualms getting you euro only E36 parts if you have a P/N

I used to do this years ago, but heard that BMW NA cut the dealers off from Euro parts goodies at some point.

Anyone confirm/deny?

Neil

[das borgen]

I used to do this years ago, but heard that BMW NA cut the dealers off from Euro parts goodies at some point.

Anyone confirm/deny?

Neil

Actually, my recollection is from years ago, probably from before they stopped that policy.

I explicilty remember getting a euro M3 radiator cover from the dealer (much cheaper than anywhere else actually) and them not even batting an eye at needing to get it from a stockhouse in Germany

[Braymond141]

Actually, my recollection is from years ago, probably from before they stopped that policy.

I explicilty remember getting a euro M3 radiator cover from the dealer (much cheaper than anywhere else actually) and them not even batting an eye at needing to get it from a stockhouse in Germany

Some parts are blocked, some parts are not. There is no rule and there is a lot of confusion with this. Many US parts counter guys will tell you it is NLA instead of blocked (or NLA when more are in production).

For example; You cannot order the Motorsport belts unless the US dealer is Motorsport certified. Any regular dealer will just say they are NLA.

[das borgen]

Some parts are blocked, some parts are not. There is no rule and there is a lot of confusion with this. Many US parts counter guys will tell you it is NLA instead of blocked (or NLA when it more are in production).

For example; You cannot order the Motorsport belts unless the US dealer is Motorsport certified. Any regular dealer will just say they are NLA.

what's an example of a dealer that's Motorsport Certified?
I'll get me some belts!

[williamm3]

Braymond141, you are wrong. The LTW did come with a duct with plastic sides.

[Braymond141]

Braymond141, you are wrong. The LTW did come with a duct with plastic sides.

Notice how I said it isn't specific to the "EL TEE DOUBLE U"? Read what I wrote more thoroughly. I'm fully aware the underpanel is the metal middle with plastic leg version. I own two of them. I was merely pointing out to stop using the Lightweight as the basis for all parts and not some hodgepodge of standard US E36 parts riveted to a metal middle section for LiGhTWEiGHT use. These parts came from other cars.

Neil,

There is no such thing as a "LTW" duct with plastic sides. You're talking about about the GT duct and the plastic sides are standard. These parts are indented for cars with oil coolers. The Lightweight has very few parts specific to it with almost everything coming from better European cars.

I'm not wrong, but I am guilty of piling it on to all the LTW is life owners.

[golgo13]

This is super helpful since I'll be needing to switch over to different ducting once I install my Z3M S54 radiator and oil cooler in my USDM E36M.

I might just fabricate something out of aluminum since it's cheaper, easier to source and I don't need to argue with anyone over parts semantics.

[sirhodjibob]

Could you tell me where this piece on the far left of your picture mount onto?
PN# 51718135939

I have that part sitting on the floor and I still have no idea where it would possibly go. It's not wide enough to go across the bottom.

- - - Updated - - -

Also if anybody is able to tell me where this piece would mount onto?
PN# 61678353884
Attachment 677294
I believe its part of the region where the intensive cleaning reservoir/Euro coolant expansion tank goes;
Attachment 677295

It might be just based on its diagram location in RealOEM but it also looks like the triangular part that clips in near the entrance to the air intake system.

[sirhodjibob]

This is super helpful since I'll be needing to switch over to different ducting once I install my Z3M S54 radiator and oil cooler in my USDM E36M.

I might just fabricate something out of aluminum since it's cheaper, easier to source and I don't need to argue with anyone over parts semantics.

Way cheaper. Forgot to add to this thread you also need to replace the side ducting around the radiator part #s 51712256543 and 51712256544. The euro cars also have additional ducting behind the radiator around the fan but I just kept the US shroud.

[sirhodjibob]

That's correct. In the first post is my car's original North American spec 99 M3 side ducting. In order to support the oil cooler duct you need the side ducting off the Euro car.

Here's the finished product with the M3 GT side ducting (part #s 51712256543 and 51712256544). I do believe all Euro spec cars used this ducting though, not just GTs, but I used an M3 GT VIN to check the part numbers since I was using the unique GT aluminum undertray as well.

[bluptgm3]

Thought I would collect all the part numbers in one post, comments by fellow BF member

Example VIN extracts
EA40016 - M3 GT
EH07222 - M3 Lightweight

Parts:
51712268673 - GT aluminum air duct
51712253303 - front oil cooler duct
17212227344 - rear oil cooler duct (I didn't use this as it attaches to the factory oil cooler which I don't have)

51712256543
51712256544
- side ducting around the radiator
Hardware: 51718242741, 07129904150, 07119901299, 07149126885 (you can reuse yours but I like new stuff)

I also installed new front fender liners and "pork chops" since the originals were cracked. If you are going to use the GT front splitter you don't need the pork chops. I also ordered 51-71-8-135-939, air duct bracket. However, I have no idea where it installs. You'll see it on the parts diagram. If you figure it out let me know. That said everything fit together securely and properly as is.

Fender Liners
51711977047 Covering left
51711977048 Covering right

Pork Chop
51711977117 Support left
51711977118 Support right

Hardware
07129904217 Body nut (2)
07119901299 Hex head screw (X)
63171367868 Expanding nut (X)
07129904150 Body nut (6)

51712233361 Front left brake air duct
51712233362 Front right brake air duct

Sent from my iPhone using Tapatalk

[BLAKE AuST]

I have a 1994 m3 euro, and bought 17212227344 ages ago as I thought I was missing it and didn't realize the metal version of that undertray thing (51712268673) was different to the plastic part I had already.

Now that mystery(for myself) is solved I understand what how 17212227344 fits. Realoem has this part around the wrong way in its drawings!!

51712268673 is much larger than it looks and goes back past the oil cooler to just before the sway bar, there are 3 holes you can see along the top(in the image) and that whole edge is bent up slightly.
ES4IBKJ.jpg

This picture is of 17212227344 in its correctly mounted position, the thin edge dosn't actually mount to the oil cooler as such, it slides in between the oil cooler and the water radiator, and is held in place once 51712268673 is installed
[/QUOTE]

17212227344 basically directs hot air away from the engine and under the car, once I test fit 17212227344 in my m3 it all made sense. Tho I have no idea what that big cutout is for?

[blckstrm]

Thought I would collect all the part numbers in one post, comments by fellow BF member

Example VIN extracts
EA40016 - M3 GT
EH07222 - M3 Lightweight

Parts:
51712268673 - GT aluminum air duct
51712253303 - front oil cooler duct
17212227344 - rear oil cooler duct (I didn't use this as it attaches to the factory oil cooler which I don't have)

51712256543
51712256544
- side ducting around the radiator
Hardware: 51718242741, 07129904150, 07119901299, 07149126885 (you can reuse yours but I like new stuff)

I also installed new front fender liners and "pork chops" since the originals were cracked. If you are going to use the GT front splitter you don't need the pork chops. I also ordered 51-71-8-135-939, air duct bracket. However, I have no idea where it installs. You'll see it on the parts diagram. If you figure it out let me know. That said everything fit together securely and properly as is.

Fender Liners
51711977047 Covering left
51711977048 Covering right

Pork Chop
51711977117 Support left
51711977118 Support right

Hardware
07129904217 Body nut (2)
07119901299 Hex head screw (X)
63171367868 Expanding nut (X)
07129904150 Body nut (6)

51712233361 Front left brake air duct
51712233362 Front right brake air duct

Sent from my iPhone using Tapatalk

I don't know why I've been absent this whole time, but I was just catching up tonight and planning to collect everything - so thank you for saving me the work!

So, I'm doing a bit of the slippery slope dance tonight.

I got rear-ended about 6 weeks ago, and finally got the insurance check yesterday.

Needing a new trunk lid, I decided after a lot of agonizing to get a GT/LTW/whatever-I-need-to-call-it-to-avoid-angering-certain-people 4-piece high rise wing setup from Driftshop in the UK (or France or wherever they're located).

Not wanting the car to be unbalanced, and having been wanting the GT/LTW/whatever-I-need-to-call-it-to-avoid-angering-certain-people front splitter forever, I decided to pull the trigger on a good rep I recently found (with hardware included).

Now we're to the slippery slope part. The JTD split underpanel I installed years ago has been surprisingly great - it ties everything together nicely, allows keeping all facroty hardware like the pork chops if you like them, is far more robust than you'd expect, etc - but it won't permit the installation of the LTW front splitter, so I need to find a different solution.

Funny how Google brought me back to this conversation.

Anyway, my stock stuff is fairly thrashed, so I need to replace all of the original ductwork, so this big laundry list of parts is great - I'm sure I need most of it, including the fender liners.

But this line: "If you are going to use the GT front splitter you don't need the pork chops."

How? The splitter is moveable. How does it replace the pork chops and tie into the fender liners?

Question #2 is this: is the cutout in the front of the GT aluminum air duct to accommodate that center bracket for the splitter? This looks like a hole that would let air out, but I assume the high center section of the splitter blocks that off. And I also assume that the oil cooler duct is an either/or situation with the splitter - you can run the splitter or the oil cooler duct to plug the hole, but you can't really do both (nor is there a reason to run both).

Question #3: Have you guys found you have to take the whole front of the car off to install all this stuff, or is there enough access with the front bumper removed to get everything installed without removing the headlights and nose panel?

[Edit] Of course I forgot something:

Question #4: How does the LTW plug the space the oil cooler takes up since it was not running the oil cooler?

[Braymond141]

The rectangular hole in the GT underpanel is to clear the center tray mounts that come down off the bumper carrier.

Porkchops; You can buy 51711977117 Support left 51711977118 Support right or if your M3 ones are still in good shape, you can separate the wind deflector hump from the porkchop. You can see how the GT underpanel has a tab on either side to tie the porkchop and fender liners in.


Standard M3 porkchop. Note that 5171197717/118 are spot plastic welded to the wind deflector hump.



I swear, you're the only person to have anything positive to say about that JTD underpanel. Biggest pos ever. I'd rather you offend certain people with LTW-insertnonltwparthere

[golgo13]

That reminds me, I need to dig out my porkchops and sell them.

[blckstrm]

The rectangular hole in the GT underpanel is to clear the center tray mounts that come down off the bumper carrier.

Porkchops; You can buy 51711977117 Support left 51711977118 Support right or if your M3 ones are still in good shape, you can separate the wind deflector hump from the porkchop. You can see how the GT underpanel has a tab on either side to tie the porkchop and fender liners in.


Standard M3 porkchop. Note that 5171197717/118 are spot plastic welded to the wind deflector hump.



I swear, you're the only person to have anything positive to say about that JTD underpanel. Biggest pos ever. I'd rather you offend certain people with LTW-insertnonltwparthere

Heh - I know, I don't know why I settled on it ten years ago when I was trying to plug the hole left by the factory tub. That was the first thing I ever did to the car. Maybe that explains it?

I have drilled a couple bonus holes to tie everything together AND kept the pork chops in addition to the JTD panel, so I'm sure that all helps keep it tight. I'll admit it's a pretty flimsy item - I'm excited to have a real splitter in place.

It's odd - my porkchops don't have the wind deflector bits - they're pure pork chop. I didn't know there was more to the part. I guess I ordered the wrong bits back when I first replaced all this stuff (before I learned how to use RealOEM). Looking at the part on ECS I see how this is shaped and can see how it would interfere with the splitter whereas the porkchop alone wouldn't. But that's good news.

My only remaining real question is blocking off the bottom where the oil cooler would go. I can probably fabricate something out of some aluminum, but is there a factory bit that plugs the oil cooler hole? The oil cooler duct is pretty spendy to just cut it up with slots to let the splitter supports penetrate it.

The LTW had to have something, no? What's the point of refreshing all that ducting and then leaving a gaping hole under the radiator?

[blckstrm]

Ok, I think I finally found the oil cooler block-off: 17112227690

It's not listed with the other ducting in RealOEM - it was listed with the radiator.

[sirhodjibob]

Ok, I think I finally found the oil cooler block-off: 17112227690

It's not listed with the other ducting in RealOEM - it was listed with the radiator.

Are you using that with the aluminum air duct? If so that's the piece I originally tried in the first post but never got to work. I suppose it would work with the original plastic one though (mine was missing when I bought the car).

I never did figure out what the LTW uses so I just copied the GT since I may want to add an oil cooler down the road anyways and I knew all the pieces would fit together.

[blckstrm]

Are you using that with the aluminum air duct? If so that's the piece I originally tried in the first post but never got to work. I suppose it would work with the original plastic one though (mine was missing when I bought the car).

I never did figure out what the LTW uses so I just copied the GT since I may want to add an oil cooler down the road anyways and I knew all the pieces would fit together.

Hrm... Yeah, that's the plan. Damn, I hate when stuff like this comes full circle like that and wind up where we started.

It was listed in RealOEM for everything from a 318 to an M3 (including S52) - I guess I should have been skeptical. I see slots on the sides in the aluminum air duct - I figured this piece slots in somehow. I guess not. But that should give me something to work with. I can bend and cut some aluminum sheet I guess.

Weird to get this close to a total factory solution and then just have to fab something up.

I just can't see them leaving a gaping hole under the entire radiator - there must have been SOMETHING there on the original lightweights.

I don't know - there are two diagrams for the bumper cover (one that adds the splitter) and two diagrams for the front ducting and in none of them is there a plug for the oil cooler.

I guess you have to either use the oil cooler or fab up some kind of blockoff plate yourself IF you want it sealed up.

[sirhodjibob]

I have the Euro/S54 Z3M radiator so that may have been an issue for fitting the part as well.