If you call bilstein what they want you to do with there replacement is use a ring at the shock collar that allows you to put a P30 shock in the larger 323i and early 320i strut tube, THIS 'work-around' is a real mistake in a vehicle with lowered suspension. This configuration will bottom out.
Rear Shocks
Bilstein still offers the e21 rears B46-0617, but the fronts P36-0124 are NLA.
Replacements: E30 bilsteins will fit the E21 323 strut housing. They are both the correct 36mm around, and the correct height. When looking for used shocks you might also look at the E12 or E28 shock instead as they are also bilstien P36's. The diameter of the strut. 323 and 1977 320 are the same. I know that the early 320i had larger hubs than the later 320i, and the same size as the 323i.
- All 323 used a 51mm strut tube.
- All 320 used a 45mm strut.
inner bearing, outer bearing from 09/79 320
29 X 50.29 X 14.22-------- 17 X 39.87 X 13.84
inner bearing, outer bearing till 08/79 320
31.7 X 59.13 X 15.8-------- 19 X 45.23 X 15.49
inner outer 323
31.7 X 59.13 X 15.8-------- 19 X 45.23 X 15.49
320 till 08/77, used a 51mm strut tube and vented brake disc and larger calipers to match
320 from 09/77, solid disc.
323 - same brake as 1977 320
Bilstein will explain the difference in sizes among the E21 4cyl Sport, the E21 6cyl Sport, and the E30 6cyl Sport. Valving and compression stroke within the strut are the same. They also fit the strut tube the same as the e21 323.
Bilstein East Coast # 704-663-7563Bilstein West Coast# 858-386-5900
Even though 323i front struts are No Longer Available, Bilstein does have those dimensions. Just ask them to compare the e21 323i size with the e30 6cyl/m3 size, SSDD.
Question: If E30 struts are really the same as 323's why wouldn't Bilstein recommend them as a substitute instead of the 320i struts with spacer? For that matter, why would they call 323 struts NLA in the first place?
Answer: Saying 323i e21 front struts and e30 front struts are "the same" was a bit too cavalier a term for engineering/mechanical/retail purposes. NEARLY identical is more correct. Bilstein as a wholesaler wouldn't really recommend one application over the other since they aren't a direct retailer, and don't really care where we spend our money. So when we pulled e30 HD's out of a 323i strut tubes, and called Bilstein for a little "what the hell?", they confirmed that the tube dimensions and stroke and compression were appropriate for the e21 323. On the other hand, Bilstein may not KNOW that they have struts that would fit the 323. When you buy brake calipers for your e12, e28, or e32, they don't say...also fits e9, e10 2002 with tii struts and spindles, and e21 323. That is what we are here to discover...
Korman sells makes the adapters that allow the 320i struts to work in the big tube or all the early style bushings in delrin.
