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Speedmaster's 540-inch Chevy big block project, producing 939 horsepower with boost and nitrous, was featured in the August 2017 edition of Performance Racing Industry Magazine alongside coverage of power adders, header designs, and technology previewed for PRI 2017.

Richard Holdener puts the Speedmaster Eliminator dual-plane intake head-to-head against a Trick Flow Specialties Street Heat EFI system on a modified 5.0L Ford, with dyno results revealing where each configuration delivers its advantage.

Using a junkyard 5.0L Ford topped with Trick Flow 11R heads and a Speedmaster Eliminator dual-plane intake, Richard Holdener tested 1-inch open and 4-hole carb spacers from Wilson Manifolds - measuring where each design adds power and where it trades torque.

Richard Holdener puts the BluePrint Engines 540 big-block Chevy through a progressive boost test using a Speedmaster 8-71 supercharger kit, reaching 939 hp and 866 lb-ft of torque at 11.1 psi.

What actually happens when oil pressure drops to zero and you keep driving? Richard Holdener and Chad Reynolds put it to the test on The Wheel of Death, combining controlled destruction with real failure analysis.

Running a 331 Ford stroker to 761 hp on a factory 5.0L block revealed a critical lesson: boost is a multiplier, not a solution. Building normally aspirated power first delivers more output at lower, safer boost levels.

On a 331 Ford stroker equipped with Speedmaster forged internals and a COMP cam, swapping from stock E7TE iron heads to Edelbrock Performer RPM aluminum heads delivered an 85 hp gain. The results reinforce why the order of modifications matters.

On a mild 5.7L Gen III Hemi, the Speedmaster Stack Attack individual-runner intake system produced 461 hp and 412 lb-ft of torque, outperforming a Mopar Performance single-plane intake by 35 hp with gains throughout the entire rev range.

A modified 4.8L LS equipped with Speedmaster rods, JE forged pistons, and a Vortech Ti supercharger produced 799 hp at 15.8 psi, nearly doubling the 438 hp naturally aspirated baseline. The results demonstrate the value of building NA power before adding boost.

The Speedmaster downdraft system for small block Chevy produced 401 horsepower on the dyno, tested by Richard Holdener. The video covers the full dyno session and results.

A complete top end kit for the Big Block Chevy, tested on the dyno by Richard Holdener. The Speedmaster kit delivers over 100 horsepower in a single bolt-on upgrade.

Speedmaster puts its blower components through a side-by-side shootout on a Small Block Chevy. The test measures real output differences between supercharger setups on the same engine.

A Gen VI 454 pulled from a wrecking yard produced 369 hp in baseline trim. After installing Edelbrock RPM 454-O aluminum heads, a Performer RPM Air Gap intake, and a COMP XR271HR12 hydraulic roller cam, output climbed to 481 hp and 527 lb-ft of torque.

A 383 cubic-inch LS stroker built around a 4.8L iron block produced 527 hp naturally aspirated. After installing the Speedmaster 6-71 supercharger kit with a dual-quad carburetor setup at 7.3 psi, output reached 753 hp and 625 lb-ft of torque.

A full-length 2.5-inch Hooker Blackheart exhaust system was tested against open headers on a 383 LS stroker to measure the actual power cost of running a street-legal exhaust. The results showed a difference of just 9 hp at peak, with the street system delivering 542 hp at 6,000 rpm.

A stock LQ4 6.0L truck engine was upgraded with LQ9 flat-top pistons, a COMP 54-454-11 cam, Stage 2 ported 317 heads from Total Engine Airflow, and a FAST LSXR intake. The result: 549 hp at 6,700 rpm and 481 lb-ft of torque at 4,900 rpm.

A throttle body comparison on a 427 LSX equipped with Mast Black Label LS3 heads and a CNC-ported single-plane intake showed a 12-hp gain when stepping from a 4150 to a 4500-series unit. The results confirmed that the high-flow Mast intake was being restricted at the throttle body.

Tested back-to-back against the factory LS7 intake on a 427-inch engine, the Speedmaster downdraft individual-runner intake produced 673 hp and 605 lb-ft of torque - gains of 32 hp and 34 lb-ft across the full rev range.