Who doesn't want an extra nearly 20 horsepower, and 10 extra pound-feet of torque? And what if that extra power cost less than $100, and could be installed in under an hour? Well, say hello to your new best friend: Heatshield Products I-M Shield™!
I-M Shield simply attaches to the underside of the intake manifold via its specially formulated adhesive backing that can withstand temps to a sustained 300 degrees Fahrenheit. I-M Shield creates a thermal barrier between the intake manifold and the top of the engine, minimizing heat to the intake manifold. Even modern composite intakes are susceptible to heat soak, and the heat can raise the air temps inside the intake, costing horsepower and torque. By keeping intake air temps cooler, the computer is less prone to reducing ignition timing and/or increasing the air/fuel ratio, which decreases horsepower, torque and throttle response.
On any modern electronic fuel injection engine, when air intake temperatures rise, the computer's first reaction is to reduce timing to help guard against detonation. Any time this happens, horsepower and torque will decrease. Even on engines like the Ford Coyote V-8 and GM LS-series V-8 that utilize reinforced nylon composite intake manifolds, ambient heat from the engine can "soak" the intake, raising intake air temps and causing a loss of power.
I-M Shield stops this, acting as a thermal barrier between the intake and top of the engine. Installation is easy, especially with today's intakes being dry (meaning they have no coolant passing through them). The I-M Shield installs on the underside of the intake using its integrated, heat resistant adhesive backing. It comes precut to fit the underside of the intake, and requires minimal, if any, trimming for a perfect fit.
To test the effectiveness of I-M Shield, we used a 2010 Camaro SS and the Dynojet chassis dyno at Antivenom Performance in Seffner, Florida. The Camaro used for the test had an LS3 that was modified with a set of ported factory heads, Brian Tooley Racing camshaft, headers and high-flow exhaust system, cold air intake, and custom computer tune done by Greg Lovell at Antivenom Performance.
On a hot, humid Florida day in August, we baselined the car once the engine was up to operating temperature. Results were 459 horsepower at 6,500 rpm, and 423 pound-feet of torque at 5,300 rpm.
We ran the baseline tests and then went about the easy task of installing the I-M Shield. After letting the engine cool down, we removed the intake, wiped down the underside with some degreasing solvent so the surface was totally clean, then affixed the I-M Shield, and trimmed away a little bit of material from the edges for a clean and perfect fit. Then the intake was bolted back onto the engine, everything else reinstalled, then the LS3 was run up to operating temp before we did our post install dyno run.
The results? With I-M Shield installed, the LS3 put out 476 rear-wheel horsepower at 6,300 rpm, and 434 pound-feet of torque at 5,400 rpm on the Dynojet chassis dyno. That's a gain of 17 horsepower and 11 pound-feet of torque! And that's with no tuning or other heavy work, just unbolting and reinstalling the intake manifold. Those are major power gains from installing a product with a retail price under $100.
Here's the before and after horsepower and torque numbers side by side:
I-M Shield is available for GM LS-series factory car intakes (LS1, LS2, LS3, LS6, LS7), 2011-14 Ford 5.0L GT and Boss intakes, and Ford 2011-14 3.7L V-6 intakes.
If you found this information interesting and useful to gain horsepower, we encourage you to share with your friends and online communities. And if you are using Heatshield Products Header Armor™, be sure to post a picture of your car on our Facebook page!