E36-Chassis BMW M3: Expert tips on buying, modifying and more

James Clay
BimmerWorld
bimmerworld.com

An E36 is the most rock-solid, nontemperamental BMW produced to date, in my opinion. Unlike some older models, the fuel-injection system functions flawlessly and isn’t very subject to deterioration with age or use. The wiring of the car is well laid out and protected with insulation that remains flexible, so electrical gremlins aren’t common. If you are new to this car, you chose a good one!

Like clockwork, we expect the trinity of front control arm bushings, rear trailing arm bushings, and rear shock mounts to fail on these cars, giving a sloppy, disconnected feel on the road. Stock replacement will work here, but most people upgrade to something like a Powerflex bushing with a lifetime warranty on these locations to increase suspension performance and get a more durable, better-engineered part at the same time.

If it isn’t in your service records and you have more than 60,000 miles, the cooling system needs maintenance. Do that now before you throw a fan blade through the radiator or break the radiator neck. That’ll leave you stranded, wishing you had addressed the cooling before the tow bill. 

The stock radiator has plastic end tanks, which are fine for about an eight-year lifespan. Past that time, the plastic becomes brittle and the normal vibrations of driving will snap it off at some point. Likewise, the factory water pump is a failure item, and another lifetime warranty part like the Stewart pump makes an excellent addition. 

If you are planning higher-rpm use, get rid of the engine fan and fan clutch. A fan delete kit will task the auxiliary fan with the needed cooling, and you will eliminate another piece of brittle, failing plastic.

When upgrading, people seem to think power first. There are certainly gains to be made in this department. An aFe intake not only flows better, but is shielded from engine compartment heat so you actually achieve power gains the cheap kits often miss. 

If you have a 1995-or-newer car with traction control and you can live without it, remove that secondary throttle body, put in a smooth-wall BimmerWorld silicone intake boot, and you instantly get 5 to 8 horsepower at the wheels. This is by far the best bang for the buck. 

Suspension is our favorite way to make these cars more fun, more competitive, or outright race-dominant. This model won at SCCA Solo Nationals last year, shocking the entire AWD crowd. Bilstein Sport dampers and H&R springs are the go-to inexpensive suspension, but there is a whole menu of coil-over systems out there that will make this car significantly more fun to drive–and better looking. 

Beyond better bushings to address the three stock failure locations, you should consider the rear subframe bushings as well. And if your car didn’t start life as an M3, you may consider welding in reinforcement plates in the rear subframe location. It will eventually tear out for anything past commuter use when the mileage gets up there.

Brakes are easy on this car. There are a lot of options if you’re into slowing down all that newfound power and corner-exit speed you picked up in engine and suspension upgrades. M3 brakes bolt onto all E36-chassis models, and E46-chassis 330 brakes are compatible as well. Install the M3 master cylinder at the same time to retain the proper balance. 

A good set of stainless brake lines gives you better pedal feel. Cap that with quality brake fluid and a good pad–like Performance Friction’s Z-Rated–and you’ll have better braking ability than 99.44 percent of the cars on the road.

If you want the car to handle, wrap the brakes in a 245mm or 255mm tire on an 8.5- or 9-inch-wide wheel all the way around. Factory diameter on the M3 is 17 inches, and that measurement looks at home on the car, while giving you some sidewall protection for road imperfections. An 18-inch wheel looks a little more modern and is our preference, both cosmetically and for handling ability.

Bob Tunnell
Bimmerhaus
bimmerhaus.com

There are two red-flag issues to be on the lookout for: signs of an engine over-rev and signs of overheating. BMWs are renowned for their silky-smooth-shifting transmissions. Unfortunately, their super-slippery synchros combine with cushy, NVH-damping transmission mounts to allow even experienced drivers to unknowingly execute the dreaded it-sounded-just-like-a-Ferrari-before-it-blew-up “money shift.”

Sometimes, an alert driver will recognize the sound of his rpm approaching the range reserved for Formula 1 engines and recover before the rods jailbreak for daylight. But by then, some measure of damage has typically already been done. The problem for used car buyers is that the engine will often still run smoothly with a slightly dinged valve or two. The only way to tell for sure if there’s damage is to perform a compression and/or leakdown test. If one cylinder varies more than about 5 percent from the others, walk away.

The most cost-effective gains in performance come from suspension upgrades. Several manufacturers like H&R, Koni and Bilstein offer affordable coil-over setups with spring rates and ride heights from mild to wild. Anti-roll bars are also a good way to increase the effective cornering spring rate without adversely affecting general street ride quality.  

While you’re working on the front suspension, it’s a really good idea to replace the front control arms and Q-bushings. A ball joint that lets go at your first autocross, track event or driver school can really ruin your day. Even something as simple as adding factory camber bolts and a good alignment will help get rid of BMW’s notorious mid-corner “push.”  

Before forking out the bucks for a set of coil-overs, get a recommendation from a BMW tuner like TC Kline, Turner or BimmerWorld for reasonable spring rates and ride heights based on your primary usage and where you live. What works best on a San Diego autocross course will loosen your fillings on Chicago city streets.

Simple bolt-on, first-step mods are a cold-air intake, cat-back exhaust and matching software package. This should boost power close to the 225 to 230 range at the wheels.  

For even more performance, it’s easy to add a high-flow air meter with larger injectors and another matched software package that will take you closer to 240 wheel horsepower. If you still want more power, you’ll need to go inside the engine, pop in a set of Schrick cams, toss on some Turner “shorty” headers, and add a matching software package. That will get you close to a healthy 260 horsepower at the wheels.

Those power numbers may not sound exactly like they do in muscle car territory, but the inherently superior handling of the E36-chassis M3 will help you humble American pony cars–and even a few Corvettes–with half the power.