1991 318is M42 Refresh Journey

[udubfl]

FRONT STRUTS (REFRESHED)

Got all the parts in and tackled it this weekend and got it complete.

I did have to borrow a coil spring compressor from nearby auto store with the shorter Koni''s shock to get everything installed. When disassembling, since it had OEM Bilstein shock, there was no tension.

I also got a tip from a fellow forum member about installing and ordered a new E30 Top Hat Washers (Part #31306763966) vs. using E30 Top Hat Washers since I was using a E90 Top Hat.



Used Koni provided plastic bump stop, top washer (OE version does not fit), locking washer and nut.

[udubfl]

I couldn't find any measurements at all for the 1210's against OE (at least with Bilstein B4) set-up. So, here's my measurement comparisons. Hope this is helpful for those looking for it.

Total Length (fully extended):
Bilstein B4: 24"
Koni 1210: 21 1/2"

Shock Body
Bilstein B4: 17.0"
Koni 1210: 16 7/8"
- basically the same body length. What's interesting is the E30 Strut is 16 7/8".

Shock Shaft Fully Extended (not what to call it)
Bilstein B4: 7.0"
Koni 1210: 4 1/2"
- Koni is 2.5" shorter than Bilstein B4

[udubfl]

FRONT SHOCKS (KONI 1210 SPORTS)

Wanted to share the front shocks I ended up choosing, the differences and why...

When doing my research today (circa 2026) on the internet, reddits, facebooks, forums, etc., many found Bilstein B8's to be little stiffer than Koni's. Not 100% if this is true. This was just nice to know. I ended up going with Koni's for few reasons...
1. Koni's were on sale ($200/ea vs. $250/ea).
2, Koni's are adjustable. This is a nice feature.
3. Appears the front Koni's are easy to adjust from the top.

I found 3 yellow front Koni versions that fit E30. This was little confusing but I think I found the differences:

1210: Shorter for lowered springs (mainly used on E30 M3s)
1021: Longer/extended length (mainly for E30 coupe and sedans)
2277: Used for E30 convertibles

I went with 1210's. Between H&R springs, E90 Top Hats, etc., I figured I needed something shorter than normal. Couple forums posting was happy with this set up on their E30's (non-M3). Previous owner had the Bilstein B4 (OE replacement version) with the H&R springs and E90 Top Hats, so I was able to compare the two. Just FYI, when I was dismantling the current set up, I didn't have to compress the springs. I think this is because the B4 had longer shaft with shorter springs.

Box Label:



What comes in the box:

[udubfl]

Here’s how it looked before washing it up…I thought it was completely surface rusted. It ended up being brake dust snd dirt.




Here's how it turned out after media blast and new powder coated. Good as new. Ceramic coated it as well to make it easier to keep it cleaner moving forward...at least for little awhile.

[udubfl]

FRONT DUST SHIELDS

Just waiting for some final parts to come in. I was going to get new brake dust shields. At this time of writing, new OE shields are little over $100 each. But after getting it soaped/washed and scrubbed away decades of brake dust/road grimes, decided to just refresh the OE ones. Getting it sand blasted and powered coated. It’s in great shape. Minor surface rust in small area.

Here’s how it looks right now (before refresh) after soap washing it up. It has cosmoline on some area. It’s the white/yellow stuff on the paint. Cosmoline are so hard to take off.

[udubfl]

uturn, thank you for the reco! Didn't know that one. Current set up looks like e30. I think the shop the previous owner used over 10 years ago hodgepodged it. I was missing a small washer on one strut. Trying to document everything that's going into the struts for future reference as many small parts do have part numbers on it. Thanks again.

[uturn]

There is a washer on top of the top hat. Use the one from the e9x as it's beefier than the e30 one and will spread the load.

Pn# 31306763966

Installed with the flat side to the top hat. The curved side to the strut tower bushing.

[udubfl]

Have most parts now. Still waiting for final parts to come in. Sent the front calipers to get it zinc plated and rebuilt by PMB Performance. I think I could have rebuilt it myself but I never used PMB and they specializes in Porsche/German. I am curious and always willing to support the community. Got small bolts and nuts sent for zinc plating as well.

[udubfl]

First order of business. Disassemble strut and get it cleaned up. It had some rock chips, cosmoline, etc. I thought about just sanding it down and spraying regular black chassis paint. But, decided to go with powder coating instead since it under road elements all the time and wanted this one to last for a long time. Top one is my attempt to sand. Gave up and had it blasted and powder coated. Looks like it came from factory now.

[udubfl]

Been researching and figuring out what I have before refreshing/replacing/ordering parts on the front struts. It is not OE set up as previous owner made some changes. Finally figured it out.

Current Set-Up:
- H&R Spring
- E90 Top Hat (I could tell it was not OE as it was aluminum and thicker than OE used one I have in my part bin)
- B4 Bilstein (OE replacement. Not sure why previous owner didn't use B8 since its much lower than stock)
- Foam Bump Stop was completely gone (crumbled away..I could see the residual)




New Set-Up:
I like the current low stance, so I want to ensure I don't either lower or raise the current set up
- H&R Spring (keep current one)
- E90 Top Hat (I like the current low stance, so keeping it)
- Koni 1210 (used for M3 but can be used on lowered other E30s. Read positive reviews online on Koni's vs. Bilstein B8.)
- New washers, strut sleeves, strut mounts, gland threads, etc)

[udubfl]

Where do these parts go?

😂. Good eyes! Part of my daughter’s school stuff that my wife was working on. We used to put it on people’s front yard as a fundraiser. school mascot is a rattler.

[udubfl]

With 197,000 miles now (as of April 2026), this one is not meant to be stored in the garage/covered. It’s definitely meant to be driven!

I’m currently working on the front struts. Figured with all the new front suspension/subframe bushings and control arms, etc., might as well tackle this one. I have the front struts pulled off and dissembled, Trying to figure out what’s what. The existing/current set-up has been in place since 2012 with H&R red sport springs and Bilstein yellow struts. Finally figured out I have a E90 Drop Hat too. It was hard to find this in the internet unless you were looking for it. I did not even know this was a thing until now.

Getting my orders figured out. In the meantime, sent the two struts to get it blasted and powdered coated. I think I will go with Koni strut inserts, keep the drop hat and H&R spring. I like the current stance. Will post when I get all the parts.

[RustFixer]

Hello all, I've benefited from this forum for various projects. Figured I would add some new content for those that are still here.

I've owned my 1991 318is since 2016 and been working over the years refreshing it as it needed to be. I say refresh and not restoration because while I am trying to restore its original state with OE and OEM parts, I am making some minor changes or leaving things as-is along the way. Overall, it's been pretty reliable and enjoyable to drive, worked on and own. On and off over the 9 years, I've used it as my daily driver. I figured I would start sharing and documenting some of things I am working on now and work myself backwards. Also, I could use some help along the way from you all as information and support are getting harder now as E30 and parts are becoming harder to find.

Vehicle Facts (as of 4/29/25)
Year: 1991 (production May 1991)
Model: 318is
Engine: M42
Color: Silver
Mileage: 191K (purchased in 2016 @ 171k)

Nice, always good to see another long-term owner sticking with it. A ‘91 318is is worth the effort, especially if you’re keeping it mostly OE/OEM.

I like the “refresh over restore” approach, keeps the car honest and usable. Definitely start documenting, even the small stuff. It helps more people than you think, especially now that info and parts are getting harder to come by.

What’s next on your list right now?

[ehrawn]

Where do these parts go?

[udubfl]

It's a puzzle and there's an order to put it all back together. For example, I remember you have some push pins/fasteners you need to before adding the black trim piece.



Here's how the inside bumper fits into the outer shell (painted) bumper for reference point. This picture below is the damaged version.