Hearts sank in Bimmerland last February when Dinan Engineering founder Steve Dinan walked out the door of his own company to join Chip Ganassi Racing in its effort to take the new Ford GT to Le Mans. An era certainly ended as the company, based in Morgan Hill, California, and so long praised as one of the best suppliers of aftermarket BMW hardware and software, faced an uncertain future. But whether by sheer momentum alone or the steady hand of new management, Dinan Engineering continues to turn out highly polished aftermarket gear for BMWs. Well, we’re certainly reassured after driving the 530-hp Dinan S1 M4, which sharpens and refocuses a car that in stock form is drifting in the direction of a luxury GT.
For nearly three decades, Dinan has sent us demonstrators loaded up with a range of catalog items, and in turn we’ve gushed with slack-jawed amazement. However, it’s getting harder and harder for the aftermarket to dazzle us as automakers get better at delivering ultrahigh performance on their own or through specialty sub-brands. For companies like Dinan, there isn’t a lot of low-hanging fruit anymore.
The S1 M4 isn’t like most of the previous Dinans we’ve tested, in that it hasn’t had a cost-no-object engine gutting and rebuilding. With just $7247 in engine upgrades, including a Stage 2 DinanTronics signal conditioner ($2749), a freer-flowing stainless muffler ($2499), and a carbon-fiber cold-air intake ($1999), the S1 is a relative bargain. That is, compared to the S3-R M3 we tested in 2010, which had an astounding $31,234 in engine modifications alone. Okay, so this new car doesn’t offer the audacious engine porn we’re accustomed to from Dinan, but it does claim a bump of 105 horsepower and 98 lb-ft of torque at a price most M4 drivers can afford. Yes, it’s a somewhat boutique price but still affordable.
That’s because instead of a new engine you’re buying a Dinan signal conditioner that piggybacks onto the car’s computer and shapes the incoming data to fool it into generating more boost. This is a tried-and-true method of altering engine output in an era of multiplexed and code-locked computer systems. But in a BMW it is no simple matter, owing to the complex nature of the way the engine senses its surroundings and operates everything from cam phasing to wastegates and more. If you’re going to bolt a signal conditioner into a BMW, you want it from a company that knows its business (and also offers 50-state-legal compliance and a four-year, 50,000-mile warranty). Complete review on www.caranddriver.com, by Manufacturer