The regulator controls fuel pressure for your engine. When it goes bad, signs include misfires, black exhaust smoke, stalling ...

An ultra-high-performance engine, whether in a NASCAR, a Pro Stocker, or even a heavy-duty street machine, needs an incredible amount of fuel to do what it's supposed to do at high speeds.

Unlike with carburetors (which use about 7 psi), fuel injection relies on much higher fuel pressure (usually between 38-50 psi). The elevated pressure helps atomize the fuel as it flows through the ...