What size are my struts?

[joshw02]

Thinking about going coilovers, and trying to figure out what size my struts are on my 87' 325is. I'm guessing 51mm? Can anyone verify? Thanks..

[Mr. Tasty]

Thinking about going coilovers, and trying to figure out what size my struts are on my 87' 325is. I'm guessing 51mm? Can anyone verify? Thanks..

measure circumference of housings with string. Then divide by 3.14

Only you can verify, although usually the only 45mm housings were from 83-86 models.

[Holland]

You have two options. 45mm and 51mm. 45 only came on 85 and earlier 318's and some 325's. 51mm was the standard after.

[Madhatter]

^^ 45mm also came on 320i's, right through series II cars.

[Ray Smoodiver]

^^ 45mm also came on 320i's, right through series II cars.

It's unlikely to find a 320i in the US AND A though ;)

As mentioned OP, get the string out, or the verniers.

[Madhatter]

Aren't the only people looking at these forums for reference though :). You'll also find some variations 318is too, well, you do down here. Bit of hit and miss as to what diff and suspension you find in them.

[Ray Smoodiver]

Aren't the only people looking at these forums for reference though :). You'll also find some variations 318is too, well, you do down here. Bit of hit and miss as to what diff and suspension you find in them.

Oi! I'm downunder too ;)

I've had a 320i with 45mm struts, my brother had one with 51mm so who knows!

Only way to is to measure yourself, this things are getting on nearly 30 years now, could have had almost anything done to them by previous owners.

[atmobenzin]

Oi! I'm downunder too ;)

I've had a 320i with 45mm struts, my brother had one with 51mm so who knows!

Your brothers car came with ABS perhaps?

[jeffnhiscars]

I have both sizes in my e30 "collection" and the 51mm housings are threaded on the inside so the gland nut has male threads and the 45mm is threaded on the outside so the nut is female.