Because most parts of the flat-4 engine other than the crankcase are bolted on, they are easily exchanged with larger or more high-performance items. The standard VW engine has been modified from 1600 cc (the largest factory-produced Type 1 engine) to configurations well over 2400 cc using larger piston/cylinder kits, turbochargers, and other performance-enhancing parts. A variety of other powerplants, including the VW Type 4 (also used in the 914) 2-liter flat four, Chevy Corvair and Porsche 911 flat sixes have been used. Even the turbocharged flat 4s from Subaru or Alfa Romeo have been used as well. Kits for installing Rover V8 engines have also been available. These variants tend to be mated to the stronger Type 2 (Bus, Combi) transmission. Dual carb setups are very common on Beetles (especially the 1600 cc dual port engine) as well as EFI. Also a wide range of exhaust systems are available. “Stingers” (equal-length, tuned headers with straight pipes or glasspacks) are popular in nearly any type of custom Beetle. The world record for fastest and quickest four cylinder 1/4 mile drag vehicle is held by a type 1 based engine built and maintained by vwparadise of San Marcos California. Its official run is 6.60 @ 203.94 MPH quarter-mile although unofficially the quickest & fastest has been a 6.53 at 209.98 MPH.