Our latest project car, the extra-not-fast BMW 318is, is being tweaked into a fun daily driver without going overboard.
As a recap, we bought a set of TR Motorsport wheels shod in Yokohama S.Drive tires, and some exterior trim pieces to add some youth to the face of the e36. With the easy bits done, it was time to upgrade the handling before one of us capsized.
Originally I suggested a set of HR OE Sport springs because they would work with the existing Bilstein HD struts/shocks currently installed in the car. That would be far too easy though. Mr. Milton decided he needed something more sophisticated, so he picked up the phone and whipped out the credit card. By the time he was off the phone, a custom set of Ground Control coilovers were in the process of being built.
The set up specifically ordered for the e36 was the “Street/Touring” kit with street friendly (low maintenance) camber plates, and spring rates that will work on twisty roads and autocross, but still handle the bad roads of the Bay Area. In this application, Ground Control suggested springs rates of 440lbs up front, and 550lbs out back. What’s neat about this kit is that it has M3 camber plates and sway bar mounting tabs. The plates will increase the caster angle (pushing the wheel forward within the fender), which will help with front tire clearance along with better high speed stability (because the wheelbase becomes slightly longer). The sway bar mounts are a cheap upgrade in themselves. The M3 traditionally has sway bar links that mount to the strut housing, which have more leverage than a sway bar mounted to the control arms. In this case we can use our stock sway bar with the new mounting locations for what would effectively act as a larger sway bar.
The coils took about two weeks to arrive, but they are pre-adjusted and ready to be installed on the car. This is nice because we don’t have to mess around with spring compressors. Installation is fairly straightforward: the front assemblies are held in by 3 bolts on the steering knuckle, and three nuts on top of the strut tower. The rears shocks are removed by undoing the lower trailing arm bolts, and the 2 nuts on top of each shock tower. Since the rear spring sits separate from the shocks, a quick stomp on the trailing arm helps us get the stock spring out of its perch, and in goes the new coilover spring and ride height adjuster. As a side note, we purchased a set of hubcenteric 12.5mm spacers and extended lugs to make sure the tires don’t rub on the front spring perch adjusters. Some people have reported using smaller spacers, but we wanted to play it safe.
Once everything was bolted back together, we noticed that the rear end sat a bit on the high side. Great for for a 70’s street machine, but not so much for the 4-banger Bimmer. The next day we fiddled with the adjusters and got the car sitting nice and pretty. If you plan to change the ride height often, a coat of Anti-Seize on the adjuster threads goes a long way.
Like usual, we got the car aligned later in the week before we chewed up a set of new tires. The toe was set to stock to keep the steering civil on the freeway, while the camber was set to -2.5 degrees up front, and -1.9 degress out back.
The car is without a doubt more planted. Bumps and imperfections in the road are more apparent through the steering wheel, but I wouldn’t go as far as to say the ride is harsh. Unlike your typical set of progressive rate sport springs, the GC springs are linear, meaning their full spring rate is engaged right of the bat. This eliminates the “squat” and makes for quicker corner transitions on twisty roads. The money however is in the shock valving. The custom valved Koni shocks that comprise the kit are top adjustable at all four corners. For now we wanted to see how the preset valving works before monkeying around with the rebound settings. Around town and on the back roads, the shocks do a good job at keeping the chassis in line, but have enough leeway not to knock your eyeballs out their sockets. I’m very impressed with the package and how it was set up for the 318. For a fun DD, this is more than we could have asked for.
With such a potent suspension, the thing letting the car down at this point is the lack of horses in the corral. For now this gives us the option to go to an autocross should someone catch the competition bug down the line. Before anyone gets their gears turning, this car will stay an overweight Miata for a while. Milton still needs to get a replacement for the e30 he sold. I’m still hoping it has pushrods and a themed Hawaiian shirt to match.
For those curious, here’s the actual kit that was installed on the BMW: