If you’ve been following the progress of our in-house drag radial Camaro, Project BlownZ, it’s pretty obvious that we’ve come a very long way from where we started. We make plans, take the car to the track, then discover that we have only scratched the surface of what we don’t know, and go back to the drawing board to try something new. It’s a process that any serious racer will find familiar – at the level we’re finally flying at, there are no tried-and-true recipes to follow, and every extra horsepower, hundredth of a second, and mile an hour through the traps has to be earned through hard experience.
Fortunately, our most current changes have been pretty successful. The recent switch to a ProCharger F-1X finally got us into the sevens, and one big improvement was converting to larger, four inch diameter piping from Race Part Solutions. Why the switch? It’s all about less resistance.
Air might not seem to have much substance to it, but when you’re moving as much of it around under pressure as BlownZ’s combo does, inertia and drag start to play a large role. Ideally, we want it to progress smoothly from the supercharger outlet to the intercooler’s frosty heart, then deliver it gently to the throttle body for consumption by the engine. Unfortunately, the reality of packaging all that hardware means it has to take a pretty violent trip through a maze of tubing, slamming into bends like a Labrador Retriever on tile hitting the kitchen cabinets.
The large diameter tubing, with its higher volume-to-surface-area ratio, will significantly reduce “skin drag.” Like a Boeing 737 fuselage turned inside out (don’t picture that, nervous flyers) the inside of the tube creates drag that has to be overcome by the supercharger – with less area exposed per cubic foot of air, we expect to see an increase in real airflow delivered to the intake valves.
So, where does Race Part Solutions come in? Well, they’re our go-to guys for the hardware we need to connect all this stuff together. RPS was founded in 2005 by racers who wanted to turn their avocation into a business, but not just any business – they wanted to be the kind of shop that they’d always wished for from the customer side of the counter. That means top quality, great customer service, and technical knowledge “baked in” from scratch.
Grace Under Pressure
Do the math, and you’ll see that at just 20 PSI, there is more than 250 pounds of force trying to separate any place where you’ve joined 4-inch diameter tube. That means we need aluminum cones (so that we can cut some custom transitions), V-band clamp hardware (for the ultimate in strength for rigid connections) and silicone couplers and T-bolt clamps (for joints that need some flex).
Of course, expecting any setup that relies solely on friction, a rolled bead on the tube, and the power of positive thinking to keep a silicone coupler connected at the kind of boost we’re running is asking for trouble, so we also picked up some RPS Boost Braces – weld-on links with a quick release pin that reinforce connections spanned by silicone couplers, yet still allow some flex.
Whenever you’re doing this much fabrication (in other words, ‘building any serious heads-up race car’), just like every other step along the way, there will be some glitches. But, we’ve got the right parts to do the job, so there’s nothing to do but press on!