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The guys test stepped headers, whose primaries step up in diameter, and merge collectors, which create a restriction in the collector, against good old-fashioned headers.

Engine Masters

Header Science: Step vs. Merge

Diving back into the intricacies of camshaft grinds; exploring not just split-duration cams, but how larger and larger splits affect the power curve.

The Exhaust Duration Equation

The crew tests the second iteration of Holley's throttle body EFI system.

Sniper 2 the Rescue

Freiburger's 582 big-block Chevy returns; shooting out 1050, 1250 and 1450 CFM Dominators; seeing how much difference the extra CFMs make, and how much does the tune change between them.

BIG CFM Shootout

Testing a long-told hose-length theory as well as a long-proven nitrous controller practice to illustrate how softening the hit of the nitrous can help control the power and keep a motor in one piece.

Controlling the Hit

MotorTrend reveals the people & the stories behind the machines, and takes you for an epic ride. From the makers to the menders, the drivers & the dreamers, everyone has a car story and no matter what you're looking for, with MotorTrend, its Always Moving

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Standalone air/fuel ratio gauges come with a world of tuning possibilities and pitfalls; the guys compare five off-the-shelf units, then show how things like placement, air leaks and dead cylinders can affect readings, tuning decisions and power.

A Study in O2 Sensors and AFR Readings

Whether from exhaust, transmission or any heat-generating components, controlling heat can make a hot ride comfortable, and even a hot intake charge cooler. We test header wraps and panel heat shields, to see how -- and how not -- to keep your cool.

Heat Management

The team has done intake manifold comparisons on nearly every big and small block platform, and at long last, it's big block Ford's turn; shooting out single and dual planes on a street/strip 514ci combo relating to what many BBF guys are running.

BBF Intake Manifold Comparison

The spray-bar style nitrous plate has been the standard forever; the guys put the tried-and-true spray-bar style up against the newfangled perimeter-discharge style.

The Nitrous Plate Debate

Checking to see if pushrods or valve springs affect power production, even when valve float isn't a problem; the crew tests varying combinations of valve spring and pushrod strengths.

Proper Pushrods & Sufficient Springs

The guys have run standard 14-inch round filters in the past and wondered every time if there's any difference between them.

The Surprising Findings of the Air Filter Shootout

Colder fuel makes more power; how to consistently keep fuel temps down, and what difference it really makes.

Keep Your Fuel Cool!!

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Auto parts testing and engine-to-engine shootouts; developed from the popular Engine Masters Challenge and hosted by Steve Dulcich of Engine Masters magazine, David Freiburger of Roadkill, and Steve Brule of Westech Performance Group.

S8 E20 | A Study in O2 Sensors and AFR Readings