Building an E36 BMW 325i to out-perform the M3. Really.
Here we go again - another BMW project car. Loyal readers surely remember last year's Budget Bimmer - the garden-variety '89 325is we trans-formed on a budget into a crisp-handling, cool-looking tuner car. This time we've moved up the BMW food chain to see what we could do with the used-car market's most popular German performance car: the ubiquitous BMW E36 3-Series.
If the boxy BMW E30 ('84-'91) solidified BMW's foothold in the USA, then the E36 (imported from '92 to '99) established the 3-Series as the quintessential sports sedan. In urban areas, the E36 became an essential accouterment of young professionals, as common as cell phones and Starbucks. Despite its GQ image, the E36 remained a traditional Munich-built performance sedan, popular with auto-crossers and track-day warriors alike.
While our Budget Bimmer E30 project was aimed at improving the breed with select tuner parts, the E36 project will be more ambitious: We'll modify a standard 325i sedan or coupe to equal the track performance of BMW's own factory hot rod, the iconic M3. Moreover, we'll do it for thousands less than buying a used M3.
The plan is simple: Find a decent, bone-stock '95 M3 and record baseline lap times and horsepower numbers, then do likewise with a stock 325i. Next, modify the 325i - using both aftermarket and BMW performance parts - and see how close we can get to equaling the M3's lap times.
HistoryThe E36 3-Series debuted in 1992 and was bigger and more modern than its predecessor. However, it wasn't immediately embraced by Bimmeristi enamored with the E30's smaller, lighter package.
The new 3 featured a more aerodynamic shape (0.30 Cd) and 5" longer wheelbase, and it was 4.3" longer overall. The front suspension remained basically the same, with sickle-shaped control arms and McPherson struts. (One quirk to be aware of: E36s built prior to June 1992 use a slightly different strut and sway bar not interchangeable with later cars). The rear suspension, though, was vastly improved over the E30, utilizing an all-new Z-axle, multilink IRS adapted from the short-lived BMW Z1.
Under the hood, things got even better. BMW introduced an all-new inline-six, the M50. This silky-smooth, 2.5 liter power-plant featured 24 valves and double, chain-driven overhead camshafts. Output jumped to 189hp at 5,900rpm and 181 lb-ft at 4,700rpm. In 1993, BMW added variable-intake camshaft timing (VANOS) to the M50 (coded the M50TU), which increased midrange torque and idle smoothness. When OBD2 diagnostics arrived in 1996, BMW bumped up displacement to 2.8 liters (M52), with a corresponding increase to 190hp and 207 lb-ft.
In 1995, the M3 was introduced: a 3.0 liter inline-six with hotter cams, more aggressive tuning and a higher redline. Coded the S50US, the M3 engine cranked out an impressive 240hp at 6,000rpm, with 225 lb-ft at 4,250. That's a 25% power boost over the 325i (the Euro-spec M3 3.0 delivered 286hp at this time).
The E36 was popular throughout its model run. In the USA, BMW sold approx-imately 100,000 325i and 325is between 1992 and 1995, with another 8,759 3.0 liter M3s sold in 1995.
The E36 also came with four-cylinder motors (the 318 series), as well as convertible and compact (318ti) versions.
From 1996 to 1999, BMW used OBD2 diagnostics and increased displacement of both the 328is and M3 engines, 2.8 liter and 3.2 liter, respectively. The rest of the car, body and suspension, remained basically the same from 1992-99.
Project M325iFor an apples-to-apples comparison, we're limiting our focus to cars built prior to 1996 - those with 2.5 liter engines controlled by OBD1 diagnostics. And while cruising the classifieds, we unearthed a pristine '93 325is coupe in Southern California with 128,000 miles for $6,500. A "Sport package" five-speed model, it featured a near-perfect black exterior and a flawless black leather interior - a classic, if high-maintenance, combination. Being a '93, it employed the desired VANOS-equipped M50. The Sport package added sport seats, firmer suspension and sportier 15" wheels.