Much like the 3 Series Coupe that preceded it, the 4 Series->ke3834 lineage has grown to include a multitude of trims. Ranging from fuel-efficient diesels to the more powerful 335i, and from the four-door Gran Coupe to the Convertible, the 4 Series family can satisfy a wide range of customers. Come 2015 and BMW->ke178 added a new iteration to the 4 Series. Interestingly enough, it's not a new base model that would bring a fuel-sipping powerplant to the U.S., but a performance-oriented car positioned above the range-topping 435i. Meet the 435i ZHP Edition, or the first 4 Series likely to become a collectible in the near future.

I say "collectible" because the coupe->ke141 you see here is limited to only 100 examples, making it the rarest 4 Series as of 2015.

Making this limited edition that much more important is the fact that it revives a performance package first introduced in 2003. Originally named the ZHP Performance Package, the bundle added the M-Tech II body kit, ZHP upgraded suspension parts and settings, and special camshafts that raised engine output and allowed a higher redline to the E46 3 Series.->ke290 Slotted between the 330i and the M3,->ke2366 the E46 ZHP brought "track-inspired excitement to your daily drive." More than a decade later, BMW promises the same with the 435i ZHP Edition.

Continue reading to learn more about the BMW 435i ZHP Edition.

Exterior

The 435i ZHP Edition stands out in a pack of standard 435i coupes thanks to the M Performance Aerodynamics Package fitted as standard. The bundle enhances the car's exterior by means of front and rear carbon-made spoilers and a race-inspired rear diffuser crafted from PUR-RIM, a high-quality polymer.

The coupe also received carbon-fiber-reinforced plastic (CFRP) front splitter and rear spoiler, and an M Performance twin-kidney grille finished in black.

Rounding off the ZHP Edition is a set of 18-inch, Orbit Grey, V-Spoke wheels, which come with the Track Handling Package, the M Performance decals on the rocker panels, and the stainless steel exhaust pipes with a brushed finish. Exterior colors are limited to only Alpine White and Black Sapphire Metallic.

Overall, the result is stunning to look at and bridges the gap between the standard 435i and the high-performance M4->ke4183 quite well. It's aggressive enough to stand out among other 4 Series, but without eclipsing the full-fledged M coupe. BMW should really consider a full-time production model in a similar trim.

Interior

On the inside, updates are more subtle. Highlights include the Aluminum Hexagon trim, which provides a sportier feel compared to other interior trims available for the 4 Series, gloss-black accents throughout the cabin, and an M Sport steering wheel. All three features are part of the M Sport Package that's also included with the ZHP Edition.

Additionally, the Sport Mode display has been updated to show increased power figures. Much like the exterior, the interior is sober yet sporty, a characteristic defined by the overall black layout highlighted by aluminum and chrome inserts.

A flat-bottom steering wheel and a set of racier front seats would've made the ZHP Edition even better, but I'm not complaining. BMW successfully managed to slot this special-edition car between the 435i and the M4.

Drivetrain

This is where things become a lot more interesting. Although most special-edition Bimmers usually come with no modifications under the hood, the 435i ZHP got its fair share of drivetrain updates via the brand's M Performance Power Kit, consisting of engine tuning software and an M Performance engine air intake system. As a result, horsepower increased from 300 horses in the standard model to 335 horsepower, while torque was bumped from 300 pound-feet to 317 pound-feet for models with the six-speed manual transmission and 332 pound-feet with the eight-speed automatic gearbox.

The enhanced output also translates into improved acceleration. The 435i ZHP is 0.2 second quicker from 0 to 60 mph than the standard car at 4.5 seconds and a half-second faster from 50 to 75 mph. BMW also quotes a more dynamic pedal calibration in Comfort, Sport and Sport+ modes, and an optimized exhaust sound. Making the ZHP roar more aggressively is the stainless-steel M Performance exhaust that also sheds nearly nine pounds of weight.

Chassis enhancements include Adaptive M Suspension with variable damper technology and Variable Sport Steering, and M Sport brakes. The braking package adds four-piston calipers at the front and two-piston calipers at the back.

BMW also offers a limited-slip differential with the ZHP Edition. The M Performance unit utilizes the clutch plates for a total of 30 percent lockup on acceleration and nine percent lockup on deceleration. It provides instant power to the wheel that has the greatest amount of grip to gain better traction out of tight corners. The LSD should make those track weekend more enjoyable.

Drivetrain Specifications

Prices

BMW has yet to unveil pricing for the ZHP Edition, but it did say production, which will begin in July 2015, will be limited to only 100 units. If I were to take a guess, I'd say the ZHP Edition will start from around $55,000. The most expensive version of the 435i Coupe retails from $48,250.

Competition

Audi S5

With the new Mercedes-Benz C-Class Coupe still in development as of May 2015, the Audi S5->ke2297 remains the ZHP Edition’s only German-built competitor. With 333 horsepower and 325 pound-feet of torque coming from a supercharged, 3.0-liter V-6, the S5 is right up the ZHP Edition's alley in terms output. However, it is a bit slower than the Bimmer from 0 to 60 mph, needing 4.8 seconds to hit the benchmark the ZHP reaches in 4.5 ticks. The S5 is actually slower than the regular 435i as well, but that won't bother customers looking for a refined interior with top-notch fit and finish.

The exterior is where the S5 scores some extra points, mainly due to its sinister looks, especially in black. On the other hand, some might consider its interior a bit outdated style-wise and I have a feeling the ZHP Edition would be the better performer at the track. Pricing for the S5 starts from $52,500 before destination and options.

Read more about the German coupe in our detailed review here.

Chevrolet Camaro V6

You might argue that the Chevy Camaro->ke248 isn't quite as nimble as the BMW 4 Series, especially if equipped with the track-ready ZHP package, but this might very well change with the sixth-generation car. More compact and lighter than its predecessor, the Camaro has evolved into a real sports coupe.

The new V6 model is best suited to take on the ZHP Edition with a 3.6-liter V-6 rated at 335 horsepower and 284 pound-feet of torque. Sure, it's significantly less torquey than the Bimmer, but it should be good for 0-to-60 mph sprints of under five seconds. Since there's no official data available as of this writing, all we can do is wait for more info. Pricing, as you might have already guessed, is still a mystery, though the Camaro should be a bargain compared to the 4 Series.

Find out more about the sixth-gen Camaro in our detailed review here.

Conclusion

Needless to say, the ZHP Edition is the much-rumored M435i BMW never built. It has tons of M Performance parts, an upgraded engine to set it apart from the regular 435i, and it's almost as aggressive as the M4 design-wise. The fact that it wears the iconic ZHP name makes it that much better, but the limited production run places it in an exclusive niche very few people will have access to.

All I can hope is that the ZHP Edition previews that M Performance 4 Series everyone's been waiting for so long. There's absolutely no reason why BMW shouldn't build it. Hopefully, the positive response to the ZHP Edition will sway some minds. Meanwhile, get your check books ready as this limited-edition 435i will probably sell out in a matter of hours.