Journalists constantly struggle to find new ways to describe how a car feels. For example, comparing an engine revving to redline with a pack of rabid Himalayan badgers chasing a fast-moving dinner. The boundaries of good taste are slammed back and forth like the pistons in said engine. It becomes even more complicated trying to describe a tuned car, having to express what it feels like now and how that relates to a stock version. Superlatives dance with analogies as metaphors reverberate with words not commonly used in conversation, like cacophony or crescendo.

VF Engineering has made my job easier with its recently updated supercharger kits. Yes, they're powerful, but when it comes to how they make the car feel, well, they feel stock. It feels just like the factory normally aspirated engine, there's just more of it. If you look at the dyno graphs, the new curves follow the stock curves point for point, just higher up on the page. There's no sledgehammer to the lumbar, just a smooth shove, something akin to a hydraulic press. Sometimes similes just happen.

VFE spent hundreds of hours developing the kit to the level it's at now. They didn't cut any corners either. It probably could have been made cheaper, but descriptions like "cheaper" and "almost as good" really shouldn't be associated with a Porsche now should they?

When VFE begins a design, the engine bay and hard points crucial to fitting the kit are digitized into a CAD program utilizing a three-dimensional digitizing arm. Think of a robotic arm that you see in car factories, but instead of moving on its own to weld something, it's holding a ruby-tipped probe that allows the user to set points in virtual space. It's a long way from an erector set and Play-Doh for judging fitment.

Once the area is digitized, the components are fitted virtually before all the mounting harware and plumbing is modeled. Those components are then stress tested digitally to make sure failures will never occur on the road due to fatigue or lack of strength. Flow throughout the intake system is then optimized through the use of CFD software and verified in real-world flowbench testing. The results of all this testing can be seen in the compressor inlet tube. Right before the inlet on the supercharger, the entire tube flares out to equalize flow around the opening. Apparently a constant diameter during the 90-degree bend caused starvation on the far side of the inlet. That flair, resembling a muffin top on the inlet, cured the problem.

The result of all the extra effort in construction becomes immediately obvious on the road. On startup, there's no evidence of aftermarket equipment except for slight gear chatter from the supercharger itself. Owners familiar with air-cooled 911s will likely welcome the extra bit of mechanical noise coming from the engine bay. The idle is smooth and feels completely stock. That's the whole idea according to Nik Saran, VFE's head of R&D. He doesn't want something with a big, lumpy idle, or worse, no idle at all. Factory functionality is always the main goal.

Once on the road, that factory-like driveability doesn't stop. It is, however, overshadowed by the extra thrust from the supercharger. At speed, the blower's chatter disappears and is replaced by a whooshing intake noise. Again, air-cooled 911 drivers will think someone has put a fan back in their engine compartment. It's strange how much you miss mechanical noises absent in modern cars. Manufacturers do so much work to eliminate noise that cars no longer sound like machines.

Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!