Over the past few years the E36 BMW M3 has become more affordable for enthusiasts, and commonly they're purchased with the sole purpose of modification. While some purists may think that's a shame, the real tear-jerker is that the current Honda Accord V6 makes more power!
Modifying the S50 3.0 liter OBD1 motor from the '95 M3, or the S52 3.2 liter OBD2 motor from the '96-99 M3 is easily done. The only question is what route the owner should take. Considering a stock S50 or S52 lays down about 210hp at the wheels (SAE corrected) on a chassis dyno, some normally-aspirated upgrades might keep you happy up to 245whp. If you want to keep up with the latest muscle cars, maybe a supercharger is for you. Or perhaps you need the wheel-spinning mid-range of a turbo.
Each stage has its own advantages but it's often a case of how much you can afford. So we talked to a few companies who offer off-the-shelf upgrades and have broken down your options by price.
Remember, we're assuming a 210whp baseline and gains will vary from car to car. Additionally, installation prices aren't included.
$0-1000
The best bang for your initial few bucks is a good cold-air intake (CAI), which will usually bump power over 215whp, and mid-range torque by 6-8 lb/ft. And since the kits replace the factory airbox with a conical filter, you'll enjoy a roar over 4000rpm. It's also worth mentioning that almost anybody can install one of these.
The cheapest on the market is the MSDS system. It includes a g-Force filter with internal velocity cone and fitting bracket. It's only $165 but doesn't include a heatshield to divert engine heat.
The East Coast Induction System (ECIS) retails for $239 and is CARB legal. It features a shield, mandrel-bent tube, 8" cone filter, silicone hose and hardware.
Active Autowerke (AA) has a kit for $349 with an intake runner, black powdercoated grille and K&N air filter.
For $370, Turner Motorsport's (TMS) intake system uses a carbon intake tube, heatshield and ITG filter.
Dinan's intake costs $449 but comes with a carbon intake that draws air from under the engine bay. The kit also includes a fuel pressure regulator for better top end performance. It's CARB legal and has a two-year warranty.
In addition to intake systems, there are other options like power pulleys. These replace the power steering, A/C and water pump pulleys. They can be had from TMS for about $250, and should gain an additional 5-8whp. You could also throw in a fan delete nut and traction control delete elbow from Eurosport, which will provide 2-3whp for under $100.
Apart from MSDS, the aforementioned companies provide software for both OBD1 and OBD2 cars. Coupled to their intakes, these should get you around 220whp while keeping the cost under $1000. However, you'll notice an even bigger increase in mid-range torque-usually 5-8 lb/ft.
Note: if your car's a '95 M3, we recommend the $999 TMS/Conforti Euro Intake system for the most power in this category. The use of the Euro-spec HFM (airflow meter) should give you around 220whp with a stock exhaust, providing 12-15whp around 5500rpm.