Finally, we're ready to make our Project Q properly quick... You may remember the last installment (EC 11/12) when we prepared the chassis by fitting KW V3 coilovers and a StopTech brake upgrade to our M3 sedan. In this final episode, we'll look at the process of improving the power delivery from the already fierce 4.0L V8.
To quantify the power gains, we first headed to our local dyno shop for baseline runs. RCTS Canada R&D in Calgary, Alberta graciously volunteered its time and 248C Dynojet for the test.
All runs in this article were conducted in the same climate-controlled dyno, same operator, same gear (4th), same fuel (Shell 91), same 19" wheels and tires, same tire pressure (36psi), and with "M" mode activated.
We couldn't perform all the dyno runs on the same day, but past experience with this equipment has always been extremely consistent. So our baseline runs showed a healthy 341hp and 247 lb-ft at the wheels from the stock BMW V8.
We installed a free-flowing Akrapovic Evolution titanium exhaust system. And while it's expensive at $5990, the lightweight system is a thing of beauty. It retains the dual-outlet/dual-exit rear muffler design and theflow-optimized link pipes. There's also an X-pipe that incorporates two race catalytic convertors (100cpsi) and dual resonators.
We measured a total weight saving of 52 lb with the titanium construction and loss of one pair of catalytic converters (the OEM system has four cats).
The installation is relatively straightforward thanks to excellent step-by-step instructions, and the system fitted perfectly, so it's a DIY task if you have a lift and some experience.
On the dyno, our runs improved to 357whp and 260 lb-ft with the Akrapovic system in place.
The peak gains were very good, with increases detected over a wide rev band in the mid-range and at the top-end.
The improvement was evident in daily driving thanks to improved responsiveness in all situations. The motorsport soundtrack was superb: a deep, rich growl from idle to cruising speeds. However, it rises to an aggressive motorsport roar when you're heavy on the throttle - which is just what we like from our V8s!
With the engine and chassis prepared, we turned to ESS Tuning for the real power upgrade. We'd chosen the intercooled VT2-625 supercharger system that retails for $13995.
Again, this is costly but it claims a whooping 625hp at the crank and should fully satisfy anybody's need for major power.
ESS utilizes the self-contained Vortech V3 supercharger with a high-capacity liquid intercooler system that has a cast aluminum manifold assembly to house the heat exchanger.
The kit also includes a Vortech Maxflow Race bypass assembly, Uni-belt drive with OEM-quality rollers and heavy-duty drivebelt, eight Bosch Motorsport fuel injectors (Spec 3), hard-anodized CNC brackets and hardware, cold-air intake with K&N filter, high-temp silicone hoses and an ESS oil breather assembly.
Of course, it also includes reprogrammed ECU software that's tested and calibrated to provide optimum ignition timing under all conditions. It also has recalibrated EGas for quicker throttle response, recalibrated Vanos control, precise fuel delivery, and the speed limiter is removed.
An ESS E-Flash OBD2 cable is also included to allow the installer to upload the software directly to the ECU from any Windows XP- or newer PC. This has diagnostic and code-clearing ability, and future ESS software updates can be received by email and uploaded to the car. The stock ECU software can be saved via PC and is easily restored if necessary.
The VT2-625 kit requires about 8-14 hours to install using regular tools, thanks again to very detailed instructions.
It's worth noting there are no irreversible modifications done. It maintains all OBD2 functions and is backed by a comprehensive two-year, unlimited mileage warranty. It sounded perfect to us.
After a week of careful shakedown drives and testing, we were extremely impressed with both the OEM-like drivability and spectacular thrust of power. So we returned to the dyno to quantify the upgrade.
The ESS Tuning VT2-625 supercharger kit confirmed our wildest ambitions, improving the M3's output to a sensational 514whp and 333 lb-ft. This was measured increase of 157whp and 73lb-ft over the stock engine with the Akrapovic exhaust.
The graph shows its smooth power development, and it's equally smooth when behind the wheel. Amazingly, the car behaves like pussycat until you really tip into the throttle, when it's suddenly transformed with rocket-like acceleration on par with supercars like the Porsche GT2 RS.
Rubber can be shaved off the rear tires well into third gear with the traction control off, so you need to be prepared. Fortunately, we had the good sense to improve the handling and brakes first. As they say, "power is nothing without control," especially if goal is to be really "Quick".
|Evolution titanium exhaust
|VT2-625 supercharger kit