One of many multi-stage tuned pipes that have been tested. This pipe when used on the .90 motor produced 7.2 HP at 26,000 rpm during dyno pulls. Fuel used was 80% nitro, 12 to 14% ethylene oxide & 6 to 8% oil. With 65% nitro, this same pipe gave 6.8 HP. The exhaust header & fuel system pressure pick up are shown in the photo.
