| Primary Tube Length
Determines torque above or below the peak horsepower RPM point. Shorter tubes add torque above the peak RPM point and reduce torque below. Longer tubes add torque below the peak RPM point and reduce torque above it. Primary Tube Diameter Determines peak horsepower RPM point. Use small diameter tubes on small CID engines to produce mid-to-high-RPM torque. Use large diameter on large CID engines to produce mid-to-high-RPM torque. If in doubt, use smaller diameter tubes |
