Call it a blower, call it a supercharger, we don’t care, but what we do care about it how much power it takes to spin one for a top fuel engine and how much air those suckers can, well, suck and blow! This video is super cool, and it has been a long time since I watched it the first time, but I thought I’d share it after it came up in conversation with my buddy Crosby last night. This dyno is one of only a handful that exist to test superchargers like this, and it is also used to test clutch discs. I know the guy that built John Force’s blower dyno in Yorba Linda years and years ago, and it used an electric motor that took so much power that the electric company got pissed when they’d crank it up. No foolin’!
Kalitta’s blower dyno is powered by a small block Chevrolet that, with a transmission behind it, spins up a 4,000 lb flywheel assembly to over 8,000 rpm before the clutch lets loose and spins the blower up. It really is awesome to watch. In the ultra competitive world of NHRA Fuel Category racing, having all the data and performance possible is what it takes to win. In order to put their best effort forward, they test these superchargers so that they can know exactly what each one will do when bolted onto the engine. This way the crewchief can use the data from a particular supercharger as a tuning aid. It’s smart, but man it takes a lot of work. The same goes for the clutch discs, which get an initial run in behind one of the blowers, so that the discs can be “seasoned” if you will. Data from this is also used to give clutch packs to the crewchiefs that they can choose for particular track conditions.
It really is fascinating to watch what goes into running something that is so brutal and nasty on the one hand, but that requires such precision and a gentle touch on the other.
Here is all the info on the video and dyno from the guys at Kalitta. CLICK HERE TO VISIT KALITTA MOTORSPORTS
What’s that screeching whine coming from the north end of the Kalitta Motorsports race shop, you ask? Well, friends, that is the supercharger (blower)/clutch dyno in action. It’s one of only about a half dozen in use. Using a 350 Chevy motor to get things rolling, the dyno utilizes a 4,000 lb. flywheel. Once the flywheel gets up to about 8,000 rpm it applies the equivalent of 11,080 rpm to the blower via the belt and pulley to closely represent what it gets from the power of one of our race cars. Once the blower has spun for four seconds, team members like Andy Cetwinski break down all the data from the computer to determine that the flow of air and boost are correct and assign each blower a rating based on percentage to help our Team Kalitta crew chiefs decide how each fits with certain engine tune-ups. The same apparatus is used to test torque curves on clutch discs. Pretty cool, huh?