If exhaust is used to drive the turbine while it is at its hottest, such as close to the exit from the engine, it will effectively have more volume and velocity as the hot gasses try to expand in the confined space of a header. This harnessing of heat can be used to reduce turbo spool and lag and maximize the efficiency of turbocharged applications increasing horsepower! It is common knowledge that the more air and fuel you can force into an engine, the more power it will output, to a point. Hot air is less dense than cold air and must be delivered to the engine with a leaner fuel mixture. Less air and fuel equals less power. With the exhaust wrapped, under hood temperatures are also reduced, leaving cooler air available for intake.
For an experiment we used a 2008, Dodge 2500 with a 6.7-liter Cummins turbo-diesel, featured an Edge Programmer. Here we wanted to show a few Heatshield applications anyone can do, and will net gains without sacrificing reliability fuel economy. Heatshield tape is the thinest and narrowest product for wrapping small engine parts to protect them from heat. Electrical looms, fuel lines, brake lines, and other such applications can benefit from this heat-reflective tape.
We used Heatshield Armor to insulate the Dodge’s exhaust between the cat and the Diesel Particulate Filter (DPF). Thermo-Tec’s Clamp On Heat Shield or Exhaust Insulating Wrap would be a good choice here. The new and improved flexible Clamp-On Heat Shield blocks over 95% of the damaging radiant heat of the exhaust. Wrapping headers and exhaust maintains hotter exhaust gases that exit the system faster through decreased density. Increased exhaust scavenging is produced, along with lower intake temperatures.
For the air intake tubes, we use a high grade S fiberglass, that allows us to give a mirror-like finish, makes it more flexible and more reflective. Thermo-Tec’s Cool Air Tube Heat Shield can also be used---it is laced up with 4 different colors.
We chose to wrap the air charge to intercooler pipe with reflective mat. The result will be a cooler air charge to the intercooler, and ultimately to the engine. Turbo Blanket Covers are one of the few insulation modifications specifically designed to keep heat in as a performance improvement. By wrapping the turbine side of a turbocharger in a thick insulated blanket, more heat will be retained to promote faster spool and less lag. By keeping more heat inside the turbo, temperatures under the hood will be lower and less heat will affect the induction, cooling, electrical, or other systems.
The baseline readings netted 355.39 horsepower, and 653.79 lb ft of torque. With all the Heatshield Products installed, the resulting power and torque curves show a +4 horsepower gain, and +12.5 lb-ft of torque over the baseline run! In a daily driver application.
As hot under-hood components radiate heat to surrounding components temperatures in air, fuel, electronics, coolant, and oil rise. By reducing heat soak one can reduce the affected systems, and possibly increase their lifespan, and effectiveness.
Some other good products are:
Battery Wrap Heat Shield which keeps your battery cooler in summer and warmer in winter.