Misunderstandings about intercoolers and carbureted superchargers

Misunderstandings about intercoolers and carbureted superchargers

By Chris Beardsley:   Unlike port fuel injection systems, carburetors have a unique advantage while operating on boosted engines without an intercooler. In carbureted applications, the air charge from the supercharger is significantly warmer than ambient air. When warmer air is forced through a carburetor, the atomization process is enhanced as the cool fuel mixes with it. Ever try starting your carbureted engine in the dead of winter? Now compare that to a hot August afternoon. The warmer air of the supercharger blowing through the carburetor amplifies the atomization process. The result of superior atomization is a cooler, denser air charge under pressure. The warmer air mixing through the carburetor does something else just before it cools. The heat acting on the fuel causes the fuel particles to disperse—a chemical explosive process that sends fuel in every direction with violent force. When this occurs at the entrance to the plenum, each intake runner is filled with a more evenly balanced mixture of fuel and air that enters the cylinders. Naturally, cylinder-to-cylinder distribution affects horsepower. For these reasons, the ample performance of carburetors incorporated in boosted projects without an intercooler is evident. Even common pump fuels generate impressive power, and increasing ignition timing can further the power potential using these principles. “But intercooling is better,” I hear you say. “What if I add one of those?” While intercoolers have their place in boosted performance, for most carbureted applications adding an intercooler works against you. It looks fantastic and its associated plumbing enriches any engine compartment. But, by directing the air charge through an intercooler to feed the carburetor, we lose...
Androwick: 17 Pro Stock wins, new circle track heads & 2-pc intake manifolds for small-blocks

Androwick: 17 Pro Stock wins, new circle track heads & 2-pc intake manifolds for small-blocks

By Archie Bosman:   The first air-flow specialist I watched at work was Mike Androwick Sr.  A Pennsylvania native, he had plied his trade successfully in Pro Stock racing with Larry Morgan before moving to North Carolina in 2005. Finding efficient air flow in intake manifolds and cylinder heads and then skillfully uniting it with well-judged valve train technology is a mysterious art. Yet these are the achievements of the Androwicks: father and son, Mike Jr. Now three seasons with Gray Motorsports, they dominated NHRA Pro Stock in 2018, winning the US Nationals at Indy, the championship title with Tanner Gray and powering Drew Skillman to third in points. Remarkably, over the past two seasons, Gray Motorsports recorded 17 wins and 10 runner-up finishes. For the most part, Mike’s Racing Heads (MRH) has operated in two prominent arenas: NHRA Pro Stock and Circle Track. The big-block-powered Super DIRT series in the northeast remains a strong market for MRH, yielding 7 track champions in 2018. This year, however, with promoter Bret Deyo initiating the Short Track Super Series (STSS), MRH has introduced new cylinder heads and intake manifolds for Chevrolet small-blocks. The heads adopt valve angles of 10, 11, and 13 degrees, and the intakes are offered as two-piece billet aluminum assemblies and available in different versions for different heads. MRH has also enjoyed increasing success in Dirt Modified and Dirt Late Model categories. Currently situated just south of the I-85 in Concord, NC, they are moving this month to new facilities 7 miles away. Find them at: Mike’s Racing Heads 10 St. Charles Ave. NE Concord, NC 28025 Mikesracingheads.com...