Some of the car enthusiast magazines write a story about new airbox/free flow filters from time to time. The numbers indicate a very modest 3-4hp gain. However it isn't at the axle it's at the flywheel. Remember that Kayo Ong of NYC had a high performance maker of exhausts, fabricate a "free flow exhaust and filter assembly" After spend the $$$ (thousands of dollars) he put the stock DeLorean parts & muffler back on. The only car that I have driven that "felt free at revs" was when I drove Rob Grady's BRG DeLorean. If you trying to do burn outs in a DeLorean...forget about it. Even the Countach will not do a burn out. The gears in both of the DMC and Countach are too tall. The only real effective way to make the DeLorean in to a high performance beast is to follow what the Pantera owners are doing...totally reengineering the car, from the ground up. Brakes, trans., engine, body structure upgrades, cooling, electrical, tires, rims, etc., etc., etc. Only the shape is original.