I picked up a 1991 318is slick top about a year ago that spent its previous 30 years in Las Vegas. There is a lot to the story of this car but I’m focusing on the suspension restoration for this post. The car rode like a loose, floating, squeaky, smooshy, mini-boat. I knew that I could turn it into a scalpel with the right suspension and wheel/tire pairing so I started down the path of trying to figure out what it takes to DIY a suspension swap.
After many nights of watching the @restoreit YT E30 restoration channel I slowly built confidence that I could pull off a full bushing and suspension swap among many other ambitions! Its funny how owning an E30 can lead to the scenario where your wife walks into the office late at night and interrupts you watching a video of some kid scrubbing down old rusty subframe parts and you yell ‘quiet, this is my favorite part!’
All of my builds follow the same formula, KW Suspension coilovers + Brembo brakes + HRE Wheels + Michelin tires. Since Michelin doesn’t make their flagship max performance summer tire (Pilot Sport 4S) any smaller than 215/45ZR17 it led me to choosing my wheel size, 17x7.5, which I can have custom built by HRE. 17”s are pretty aggressive for the E30 so I needed coilovers to control the ride height to make the fitment just right. I didn’t like the idea of having to cut and weld old front strut tube knuckles on lower cost coilover kits so KW provided the easy solution to my equation!
First thing to do is to remove the rear axels, after examining them I decided that while I had them off the car I should clean them up, repaint and repair boots. The before and after was pretty satisfying!
The suspension and brakes on the car were looking pretty tired, I figured out it had an Eibach Pro kit and Bilstein sports on it which wasn’t bad back in the day but they were definitely not suited for the performance I was looking for…
I pulled off the brakes and hubs/bearings using rental tools from my local autozone, turned out to be incredibly easy so long as I had the proper tools and understood how to use them…this is where the restoreit and other YT channels came in very handy. I then dropped the rear struts and springs accomplished by about 4 bolts on either side (2x strut tower, 1x control arm, 1x sway bar bracket).
The brakes were so bad I opted for a total rebuild, I completely disassembled them, de-greased them and took the bare calipers and guides to a local metal coating shop who bead blasted them and re-zinc coated them for a very affordable price! I then re-assembled with new seals, boots, guide pins and fresh grease…the end result was stunning!
The front suspension looked so rough! I used a $15 Amazon pickle fork to separate the tierod/control arm joints and the rental gear/bearing puller to get the control arm bushing off since I would be re-using it. I cut/saws-all’d the bushing out and replaced with polyurethane (M3 offset) bushings. I also bought all new control arms and tierods/boots…since they were off anyway!
Next up was dropping the rear subframe, totally not necessary for a suspension refresh but I decided I wanted to run street polyurethane bushings. I disconnected the driveshaft, took out the two main subframe bolts while the differential was supported on a jack and it came right off!
The trailing arms and differential disassembly was straight forward. The diff was unacceptably dirty and clearly needed new seals and a thorough cleaning. I put the diff in a de-grease bath and scrubbed, and scrubbed, and picked, and scrubbed and scrubbed some more until I was satisfied all the grime was off of it. As for the subframe I spent several nights researching how to remove the old bushings and ultimately decided to just burn them out!
Now I had all of the parts I wanted to have sand blasted off the car: Subframe, Trailing Arms, Brake Dust Shields, & Differential cover. I had them professionally blasted and brought them home for primer and enamel coating (besides the diff cover). I also took some time with a brush wheel and brushed/cleaned the under carriage (incredibly dirty job!) and then sprayed the undercarriage and wheel wells with a rubberized undercarriage rust shield spray (or) black enamel for bare metal parts, I didn’t get any pictures but it looks brand new!
The stock sway bar system is awfully flimsy so I decided to stiffen it up with a set of ST sport sways. I like the kit because they re-enforce all aspects of the sway bar mounting system on top of nearly doubling the gauge of the rear bar. It was also the perfect time to replace them because with all the suspension and rear subframe off the car everything was incredibly easy to access and work-on. Of-course I stripped and re-painted any brakets that were going back on the car and ordered new front endlinks (adjustable rears come with the ST kit).
The re-assembly begins!!
I ordered new front and rear bearings and restored the original rear hubs by de-greasing and wire-wheeling them, one of them had a bearing sleeve stuck on it that I had to use a cutting wheel to get off. I then re-assembled the rear subframe with the new bushings and re-mounted it to the car without the differential attached (I regret not putting the diff back on while the subframe was off because the 6 bolts that hold it to the frame turned out to be a PITA to get re-seated) I then pressed the rear bearings into the trailing arms using the same rent-a-tool I used to take them off with using techniques I learned on YT.
The KW V3s were treated with all new OE strut caps and re-enforcement plates/hardware I couldn’t help myself from taking before and after shots with the old vs new suspension side by side. I re-installed the new tie-rods and control arms for the front, attached the front sway bar and prepared for suspension re-install!
Finally the time had come to adorn my E30 with KW V3s! They bolted right in just as if they were OEM pieces. I then proceeded to re-install the refreshed brake dust shields and re-press the hubs onto the front and rear axels. I also re-assembled the Differential, looks good as new! Was a PITA to get bolted back up to the sub frame but in the end it was all well worth it! I also bought all new e-brake pads and springs, and steel braided brake lines…because you know…it was already off the car, might as well!
The cherry on top was getting to re-install practically new OE gold zinc brakes with brand new Brembo rotors and pads. The end result is absolutely pristine!
Lastly I took the car in for a brake bleed and alignment and after some minor height adjustments the job was complete! The floating is gone and she rides very firmly. The squeaks and rattling caused by old bushings was completely gone and much to my surprise the poly bushings are silent and feel very complimentary to the Coilovers, in no-way too harsh, just right for my taste. The stance is perfect, equal fender height all around the car which give the appearance of a nice aggressive rake with a lower but functional ride height. The ST Sways eliminated all of the boat-rock feeling while entering corners and she now inspires confidence in suspension predictability and capability.
The clear weakest link is now the OE 14” 65 height sidewall tires. I can literally feel the sidewall flex through the steering now and the skinny 185s are max tasked for grip with a commanding suspension pushing on them. Luckily she’s ready for a custom set of HRE’s with 215 Michelin PS4S’s. I’m sure as dramatic as the original suspension to KW V3 conversion was, the new wheel-tire package be equally dramatic to complete the formula for the E30 resto-mod build!
Check out @c2kmotorsports on IG for daily content on my projects!
After many nights of watching the @restoreit YT E30 restoration channel I slowly built confidence that I could pull off a full bushing and suspension swap among many other ambitions! Its funny how owning an E30 can lead to the scenario where your wife walks into the office late at night and interrupts you watching a video of some kid scrubbing down old rusty subframe parts and you yell ‘quiet, this is my favorite part!’
All of my builds follow the same formula, KW Suspension coilovers + Brembo brakes + HRE Wheels + Michelin tires. Since Michelin doesn’t make their flagship max performance summer tire (Pilot Sport 4S) any smaller than 215/45ZR17 it led me to choosing my wheel size, 17x7.5, which I can have custom built by HRE. 17”s are pretty aggressive for the E30 so I needed coilovers to control the ride height to make the fitment just right. I didn’t like the idea of having to cut and weld old front strut tube knuckles on lower cost coilover kits so KW provided the easy solution to my equation!
First thing to do is to remove the rear axels, after examining them I decided that while I had them off the car I should clean them up, repaint and repair boots. The before and after was pretty satisfying!
The suspension and brakes on the car were looking pretty tired, I figured out it had an Eibach Pro kit and Bilstein sports on it which wasn’t bad back in the day but they were definitely not suited for the performance I was looking for…
I pulled off the brakes and hubs/bearings using rental tools from my local autozone, turned out to be incredibly easy so long as I had the proper tools and understood how to use them…this is where the restoreit and other YT channels came in very handy. I then dropped the rear struts and springs accomplished by about 4 bolts on either side (2x strut tower, 1x control arm, 1x sway bar bracket).
The brakes were so bad I opted for a total rebuild, I completely disassembled them, de-greased them and took the bare calipers and guides to a local metal coating shop who bead blasted them and re-zinc coated them for a very affordable price! I then re-assembled with new seals, boots, guide pins and fresh grease…the end result was stunning!
The front suspension looked so rough! I used a $15 Amazon pickle fork to separate the tierod/control arm joints and the rental gear/bearing puller to get the control arm bushing off since I would be re-using it. I cut/saws-all’d the bushing out and replaced with polyurethane (M3 offset) bushings. I also bought all new control arms and tierods/boots…since they were off anyway!
Next up was dropping the rear subframe, totally not necessary for a suspension refresh but I decided I wanted to run street polyurethane bushings. I disconnected the driveshaft, took out the two main subframe bolts while the differential was supported on a jack and it came right off!
The trailing arms and differential disassembly was straight forward. The diff was unacceptably dirty and clearly needed new seals and a thorough cleaning. I put the diff in a de-grease bath and scrubbed, and scrubbed, and picked, and scrubbed and scrubbed some more until I was satisfied all the grime was off of it. As for the subframe I spent several nights researching how to remove the old bushings and ultimately decided to just burn them out!
Now I had all of the parts I wanted to have sand blasted off the car: Subframe, Trailing Arms, Brake Dust Shields, & Differential cover. I had them professionally blasted and brought them home for primer and enamel coating (besides the diff cover). I also took some time with a brush wheel and brushed/cleaned the under carriage (incredibly dirty job!) and then sprayed the undercarriage and wheel wells with a rubberized undercarriage rust shield spray (or) black enamel for bare metal parts, I didn’t get any pictures but it looks brand new!
The stock sway bar system is awfully flimsy so I decided to stiffen it up with a set of ST sport sways. I like the kit because they re-enforce all aspects of the sway bar mounting system on top of nearly doubling the gauge of the rear bar. It was also the perfect time to replace them because with all the suspension and rear subframe off the car everything was incredibly easy to access and work-on. Of-course I stripped and re-painted any brakets that were going back on the car and ordered new front endlinks (adjustable rears come with the ST kit).
The re-assembly begins!!
I ordered new front and rear bearings and restored the original rear hubs by de-greasing and wire-wheeling them, one of them had a bearing sleeve stuck on it that I had to use a cutting wheel to get off. I then re-assembled the rear subframe with the new bushings and re-mounted it to the car without the differential attached (I regret not putting the diff back on while the subframe was off because the 6 bolts that hold it to the frame turned out to be a PITA to get re-seated) I then pressed the rear bearings into the trailing arms using the same rent-a-tool I used to take them off with using techniques I learned on YT.
The KW V3s were treated with all new OE strut caps and re-enforcement plates/hardware I couldn’t help myself from taking before and after shots with the old vs new suspension side by side. I re-installed the new tie-rods and control arms for the front, attached the front sway bar and prepared for suspension re-install!
Finally the time had come to adorn my E30 with KW V3s! They bolted right in just as if they were OEM pieces. I then proceeded to re-install the refreshed brake dust shields and re-press the hubs onto the front and rear axels. I also re-assembled the Differential, looks good as new! Was a PITA to get bolted back up to the sub frame but in the end it was all well worth it! I also bought all new e-brake pads and springs, and steel braided brake lines…because you know…it was already off the car, might as well!
The cherry on top was getting to re-install practically new OE gold zinc brakes with brand new Brembo rotors and pads. The end result is absolutely pristine!
Lastly I took the car in for a brake bleed and alignment and after some minor height adjustments the job was complete! The floating is gone and she rides very firmly. The squeaks and rattling caused by old bushings was completely gone and much to my surprise the poly bushings are silent and feel very complimentary to the Coilovers, in no-way too harsh, just right for my taste. The stance is perfect, equal fender height all around the car which give the appearance of a nice aggressive rake with a lower but functional ride height. The ST Sways eliminated all of the boat-rock feeling while entering corners and she now inspires confidence in suspension predictability and capability.
The clear weakest link is now the OE 14” 65 height sidewall tires. I can literally feel the sidewall flex through the steering now and the skinny 185s are max tasked for grip with a commanding suspension pushing on them. Luckily she’s ready for a custom set of HRE’s with 215 Michelin PS4S’s. I’m sure as dramatic as the original suspension to KW V3 conversion was, the new wheel-tire package be equally dramatic to complete the formula for the E30 resto-mod build!
Check out @c2kmotorsports on IG for daily content on my projects!
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