Front Strut Information Thread!

[EFreak]

The early/late model e21 320i 4cyl model share the same front strut inserts, only the gland nut is different. The e21 323i uses a different setup altogether.

Gland nuts M45 x 1.5 (Secures the sturt insert inside the strut housing)

Early (77-79)
31321115398 (BOGE)
31321130068 (BILSTEIN) <--- Has a different Bilstein part #

Late (80-83)
31321123901 (BOGE)
31321126275 (BILSTEIN) <--- Has a different Bilstein part #


Bilstein Sport Dampners

Front: P30-0125-H1
Rear: B46-0617-H0

Bilstein Heavy Duty Dampners

Front: P30-0121-H1
Rear: B46-0612-H0


323i Specific (any year)

Bilstein Heavy Duty Dampners

Front: P36-0223-H0
Rear B46-0612-H0

Gland Nuts M48 x 1.5

31321117376 (BOGE)
31321130069 (BILSTEIN) <--- Has a different Bilstein part #

[Jester323]

Thank you very much for posting this, this is good stuff that I always forget the specifics.

For those of you needing new Bilstein (or the correct Bilstein) gland nuts, call:
AFTERMARKET & MOTORSPORTS
HEADQUARTERS - WEST
14102 Stowe Drive
Poway, CA. 92064
1-858-386-5900

For those of you wanting to get your Bilsteins rebuilt click here for pricing and here for the work order form

I also suggest that you ask them for the gland nut installation tool when you call, it's only $5 and works much better than a pipe wrench.

[E21Favuzzi]

Thanks for posting. This would be great info to add to the FAQ thread.

[Beam318ti]

Since Bilstein no longer makes Front Sport Strut inserts for the E21 323i, and if you want to use the E21 320i Bilstein Sport inserts on the 323i strut housing, then you would need the following gland nut from Bilstein--Bilstein P/N: B4-B30-U232A1.

The 323i front strut housing has a 36mm diameter. The 320i strut insert has a 30mm diameter. So, you need a male gland nut that has an inner diameter of 30 mm and a outer diameter of 36mm.

[Tom D]

The 323i front strut housing has a 36mm diameter. The 320i strut insert has a 30mm diameter. So, you need a male gland nut that has an inner diameter of 30 mm and a outer diameter of 36mm.

beam, i going on the record so you don't confuse anyone.

320i 45mm strut od, uses a 38mm insert (shock) which has a piston size 30mm
323 51mm strut, uses a 45mm insert, and has piston size of 36mm.

see my tread "koni adjustables and ground control"

[Beam318ti]

beam, i going on the record so you don't confuse anyone.

320i 45mm strut od, uses a 38mm insert (shock) which has a piston size 30mm
323 51mm strut?? someone help me out here, and has piston size of 36mm.

see my tread "koni adjustables and ground control"

Tom,

Thanks for the clarification. I measured the OD of the 323 strut housing with my digital caliper and you are correct in that it is 51mm.

I will be doing my front suspension this weekend so I will confirm any other measurements if they are any different from what is stated above.

[5senses]

Awesome.. faq eligible

[Sellick]

Haha, this would have been very helpful to me just three days earlier when my car was having gland nut issues.

One thing I can add that might help...

Part # for a post-80s bilstein gland nut is B30-629 F1

[ZM Blue Devil]

Reviving this old post, cleaning up the shop and found NOS 31321126275 2 each. E21 for Billys.

$40 shipped for the pair.

L

[mdschurtz]

i would really like to know if there is a koni single adjustable shock to use on an '83 320i.

[Tom D]

yes, it's what i'm running now. i will have to look up the part number for you.

i like them. i've been a bilstien guy for 30plus years and now i'm also a fan of koni yellows.

[Tom D]

these are the strut inserts i'm using.

koni 8641-1072 Sport

[NIS323i]

i would really like to know if there is a koni single adjustable shock to use on an '83 320i.

I have the yellow sport version and like them very much, but finding the front ones is very very hard, you might have to look at foreign ebay sites (Germany) for that.
Below is a link to some Koni Shocks, however, the one for the rear is the yellow sport version and the other one (for the front) is the red version. The red one is adjustable as well, but will not be as stiff as the yellow sport ones.

http://classicgarage.com/e2119751983.html

[Allenwilson33]

Another "wish I'd seen this before installing moment."
Actually my KYB Excel-G inserts didn't fit in the strut housing at all. In a panic, I went along with my welder's idea to remove the outer tube and refill the hydraulic fluid. The results are, as anyone can imagine, poor due to leakage.
I contacted KYB to inquire about the non-fitment issue, but I thought I'd poke around here first to find out if anyone else had trouble with the front strut inserts for 83' 320is made by KYB, model Excel-G, Part Number 363016.

[Allenwilson33]

these are the strut inserts i'm using.

koni 8641-1072 Sport

i purchased a pair of KYB Excel-G strut inserts, but they didn't Ervin come close to clearing the opening. I emailed KYB in a request for advice, but they wanted pictures, which I can't do until I remove the whole arm again. Are the Konis tight fit? Or did you bore out the housing at all?

[tripletriumph]

About to do an install of KYBs this weekend, wondering if you guys heard back from KYB or what you ended up doing? Thanks!

[nickylemns]

I am confused, now that the larger diameter Bilsteins for the 323i are NLA, what should I put inside my m20 strut housings? Is there a direct replacement or should I just see about getting my old shocks rebuilt?

[Tom D]

well you could get them rebuilt or you could buy ones for the smaller 45mm struts and then use a spacer so they don't bounce around.

since the difference between the larger 51mm and the smaller 45mm struts is only 6mm then a ring of duct tape an 1/8" thick around the damper would take care of it.

[JBasham]

Another source for the Bilstein adapter/gland nut is Bavarian Auto, part number 45 0424, $60 for the pair and they usually have stock on hand.

[nickylemns]

well you could get them rebuilt or you could buy ones for the smaller 45mm struts and then use a spacer so they don't bounce around.

since the difference between the larger 51mm and the smaller 45mm struts is only 6mm then a ring of duct tape an 1/8" thick around the damper would take care of it.

Ooh I see. So you essentially the original diameter shocks are NLA, but either Bilstein or Koni, can match you something, and you just shim them in so they dont bounce around. Gotcha. Thanks for the clarification Tom

- - - Updated - - -

I used the part number from the beginning of the faq for 323i Billstein HD's.

323i Bilstein Heavy Duty Dampners
Front: P36-0223-H0

I called Bilstein Aftermarket & Motorsports west (the # Jester listed) and gave them this part number to which they relayed me the new part # 34-002230, that corresponds with the old one one.
Here is what I got

http://cart.bilsteinus.com/productsearch/34-002230

I also cross referenced the 320i hd # for the fronts.
320i Bilstein Heavy Duty Dampners
Front: P30-0121-H1

They came back to me with the new number 34-001219. Here are those.

http://cart.bilsteinus.com/productsearch/34-001219

So the old 320i hd's # now corresponds to a 30mm insert, and the old 323i hd's #, now is a 46mm insert. You can see where it shows on the site, the old part number listed as well. Rear Hd are the same for both 320, and 323. The old B46-0612-H0 part number now corresponds on the Bilstein site to 24-006125 which can be seen here:

http://cart.bilsteinus.com/productsearch/24-006125

So for my 1980 323i Im thinking im going to order two 34-002230 front bilstein Hd's and two 24-006125 rear bilstein Hd's along with two 05 0424 gland nuts from Bav auto, or more likely SSF. Rebuilding both of my old front shocks would be $126 a peice, and would take too long, ill probably do it eventually. Long run,

[Tom D]

being a long time bilstien user I have recently changed to koni and have absolutly no regrets.

[nickylemns]

being a long time bilstien user I have recently changed to koni and have absolutly no regrets.

I wouldnt doubt it Tom. On my fathers 69 Camaro we put on all the Hotchkis stuff on there, with red Koni adjustables, and its a great product for sure. I ended up finding some solid 323i Bilsteins over at Double 02 salvage over in Hayward for 250 bucks so I went that route. I did however call and talk to the guys at "CAtuned" up in Sacramento, who are apparently building a fully adjustable kit for our cars. Now that the dock strike is over, their shipments for all the seal components are on their way, and they clarified that they will be offering both 45mm, and the larger 51mm kits for the 323i. Im looking forward to seeing how that plays out, especially as they are fairly local...

[Masochist Eric]

Im on ECS to order Billy HDs for my 1980 E21. They offer two B6 "performance strut insert" options: part #34-002230 with a inner strut diameter of 48mm, as well as part 34-001219 with a inner diameter of 45mm. They claim both will fit the car. I assume from reading above the 45mm ID is the one to get?

[mxl556]

If you want HD's you need 34-001219 fronts and 24-006125 rears. B6 = HD, B8 = sport.

Max

[HipMF]

Posting here, since this thread already has all the other part numbers and seems to come up in google searches more often:

Bilstein part numbers for e21 gland nuts. You should be able to buy these from any Bilstein distributor. I was able to get them directly from Bilstein East. Bilstein West was not so helpful. YMMV.

Early:
B4-B30-U226D1 RINGNUT ASSY. M45X1.5, IST

Late:
B4-B30-U232F1 RINGNUT ASSY. M45X1.5, OST

"OST" means outside threads (male), and "IST" means inside threads (female)

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