Please note that this heat shield fits IS500 per photos in the photo gallery for this product!

This product improves on Lexus intake design and consequently improves power delivery. Please note that this product is also available together with our Carbon Intake Elbow in a package.

Sometimes the best solution to a problem, is also the simplest solution. Years ago, when we set out to design a new intake for the RCF/GSF, we discovered that we could not improve upon the airflow of the original intake air box. Introducing a fancy looking intake that makes no power, or worse results in a loss of power was not an option. However, we did discover a major shortcoming in the design of the RCF/GSF intake box.

As shown in the datalog below, the RCF/GSF intake box suffers from significant heat soak. I turns out that when the secondary intake “flapper” door opens on the intake box at about 3500rpm, the intake box is sucking in hot air from under the hood. A simple datalog shows that with an ambient air temperature of about 85F, and cruising at about 40mph and 3000rpm, our intake air temperature was about 91F. However, as we accelerate and the flapper door opens, intake air actually rises substantially up to 118F! So clearly we have a design flaw in the OEM intake, because as air speed increases, we would actually expect intake air to decrease with greater airflow to the front of the car.



Datalog below shows intake air temperature with our new RCF Carbon Fiber Intake Heat Shield. With the heat shield in place, temperature only increased by 5 degrees!



The bottom line is that intake air temperature directly influences HORSEPOWER. This is not something that can be observed on a dyno with the hood open, but in the real world, where you drive with the hood closed, reduction of intake temperature is a must.

How much power can you expect to make with our GS F Carbon Fiber Intake Heat Shield? Dyno manufacturers apply a correction factor to dyno results based on temperature. These correction factors typically adjust HP by 1% for every 10 degrees. Therefore, comparing the 22 deg F temperature difference with and without our heat shield, a simple modification like this intake duct will add 2.1% power increase, or about 11 hp.

So, there you have it, our GS F Carbon Fiber Intake Heat Shield gets you about 11hp, very affordable, and LOOKS GREAT TOO!