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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.

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.

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.

Starting at 388 hp, a Speedmaster 383 stroker gained nearly 100 horsepower through three targeted upgrades: CNC-ported heads, a more aggressive cam, and a single-plane intake. Each swap shifted the torque curve higher in the rev range, illustrating the direct relationship between component selection and where an engine makes its power.

A 331 Windsor stroker equipped with stock E7TE heads produced 353 hp. Swapping to Trick Flow's as-cast Twisted Wedge Track Heat 170 heads raised output to 439 hp and 437 lb-ft, with gains across the full rev range.

A 347ci small-block Ford built with Speedmaster forged internals and a CXRacing twin-turbo system produced 1,003 hp and 891 lb-ft of torque on the dyno. The key was upgrading from restrictive T3 turbine housings to properly sized T4 units with precise boost control.

A Dart SHP 363 stroker equipped with a Speedmaster Parker Funnel Web intake produced 563 hp naturally aspirated, then reached 775 hp and 727 lb-ft with a 200-hp ZEX Perimeter Plate nitrous shot - exceeding the kit's advertised rating.

Starting from a stock 5.3L iron block, this 383 LS stroker used a Speedmaster forged 4.0-inch crank and single turbo to reach 1,015 hp at 6,300 rpm on 16.4 psi of boost.

Horsepower is torque multiplied by rpm. This dyno series isolates the individual contribution of cylinder heads, camshaft, and intake manifold on a Speedmaster 383 stroker, demonstrating how each component shifts the torque curve and where the trade-offs occur.

A 347 Ford stroker built with forged internals, AFR Renegade heads, and a Speedmaster Funnel Web intake produced 519 hp naturally aspirated. After fitting a CXRacing twin-turbo kit adapted for blow-through carburetor use, the combination reached 919 hp at 15 psi with power still climbing.

A back-to-back dyno test on a 383 stroker quantifies the power hidden behind rotating mass. Swapping from a 55-pound steel flywheel and drive plate combination to a 29-pound aluminum setup delivered a measurable 7 hp and 9 lb-ft gain across the entire rpm range.

A side-by-side dyno and flow bench comparison of eleven Chevrolet LS cathedral-port cylinder heads, tested on a 408 stroker. Results cover peak power, average torque, port volume, and airflow from stock LS1 castings through dedicated aftermarket offerings.

Starting with a production 460 block stroked to 557 cubic inches, this build combined CNC-ported Trick Flow A460 heads, a COMP drag-race roller cam, and a dual-Dominator tunnel ram to produce 931 hp and 757 lb-ft of torque - all naturally aspirated.

Built around a Speedmaster 4.50-inch stroker crank and rods, this 557-cubic-inch Ford big-block topped with Kaase P-51 heads delivered 754 hp on pump gas and 1,014 hp with a 200-hp nitrous shot.

A Speedmaster Chevy LS1 396 cubic-inch stroker crate motor put down 533 HP (398 kW) on 98-octane pump fuel during dyno testing at Sydney Speed Supplies.

This installation guide covers the essential steps involved in fitting a Speedmaster stroker kit, from initial teardown through final assembly. Watch the full walkthrough from Sydney Speed Supplies.