Monday mailbag

Q: What is the ideal cruising RPM, and why is it important? A: Cruising rpm—that is, the speed at which your engine’s crankshaft rotates at a given sustained speed—has an […]

Q: What is engine quench? … A: Quench is the distance between the top of the piston at TDC and the cylinder head surface. It is also called “squish” or […]

Q: Can I use a fuel injection system to control my ignition timing? … A: Yes. Most fuel injection kits will work with your existing ignition system. All they really […]

Q: How does an ignition coil work? … A: Ignition coils are electrical transformers. They convert low voltage to high voltage through a process called induction. There are various designs, […]

Q: Why do I need to use antifreeze? … A: The fluid you use in your engine’s cooling system can affect its performance. For most vehicles, a 50/50 mixture of antifreeze and […]

In a liquid cooled engine, the thermostat is a valve installed between the water pump and the radiator. It controls when the radiator starts to cool the engine. It’s job is to […]

Q: How can I figure out if these headers will fit my vehicle? … A: Exhaust headers are designed to fit a specific combination of engine and vehicle. Just because a […]

Q: Can you explain the difference between “4-1” and “Tri-Y” collectors? … A: The collector is where the primary tubes merge together. 4-1 and Tri-Y are the two main types […]

Q: What is rod ratio? … A: Rod ratio is the relationship between the Connecting Rod Length and the Stroke Length of the crankshaft. How is it calculated? Use the following formula to calculate rod […]

Q: I have a 1994 Ford F-150 with a 5.0L engine and factory mass airflow sensor. I just had the heads redone and installed a Trick Flow Stage 1 camshaft. […]