If you've heard it once, you've heard it a thousand times-heat is the killer of engines. Managing it properly is critical in maintaining engine longevity and making power. This month, we evaluate six products that claim to make power by keeping heat in its place. But unlike other mags that simply say you should do something and leave it that, we're giving you the numbers. By installing each and putting them through their paces-road, temperature, and dyno testing-we show you exactly what to expect by adding them to your modified import. Some are common; others not so much, but each represents a different approach to making power through heat management-something particularly useful (if not downright vital) during these hot summer months.
Thermo-Tec Exhaust Insulating Wrapand Turbo Insulating Kit
What It Does: Manages heat to decrease underhood temperatures and increase power.
How It Works: Wrapping a turbine and turbo manifold with insulating material decreases the amount of heat energy radiated from them, forcing more to pass through the turbine. Hot gasses are expansive, and directing more heat through a turbine wheel will cause it to spin faster, increasing spool and power production.
How It Was Tested: Carter's SR-swapped '91 240SX was driven to G-Dimension in City of Industry, Calif., where resident Nissan guru Stephen Rhim strapped it to the Dynojet in preparation for baseline runs while I fit Auto Meter probes underhood, monitoring temperature in three key locations above the manifold and turbo. After starting the car cold and allowing it to idle to maximum temperature, three pulls were made to establish an average baseline power number, while maximum underhood temperatures were tracked along the way. After wrapping the manifold with Thermo-Tec's exhaust wrap and the S14 GT2560's turbine in turbo insulating material, the test was repeated and final numbers were documented.
What It Delivered: Compared to baseline power and temperature numbers, installing the Thermo-Tec products increased power output by 10.7 whp and 12.6 lb-ft of torque, and dropped underhood temperatures by 30 degrees.
Notes:
Wrapping the downpipe shouldn't affect power production in and of itself, but we theorize doing so could reduce underhood temperatures even more, which may result in an additional pony or two on the dyno. Additionally, look for even bigger power increases from wrapping manifolds that are closer to intake or intercooler piping than our 240SX's.
Hondata Heatshield
What It Does: Decreases intake temperatures by decreasing heat transfer from an engine to its intake manifold