Hondata, Inc.



Heatshield Gasket

Installation Guide














The Hondata Heatshield Gasket is designed to reduce the intake air temperatures by up to 54F/30C. This reduction in temperature can result in horsepower gains of 3% to 9%, although 3% is the average. Unlike normal gaskets, this gasket is reusable.


Hint: Do not have an air filter sitting open under the hood. Underhood temperatures can be easily 15-20 degrees Celsius hotter than outside the car robbing you of 4-6 % of your power potential. Duct cold air from the front of the car to a sealed air filter box.


Tools Needed

        12 mm box and open ended wrench

        12 and 10 mm sockets and extensions

        Screwdrivers and pliers

        Magnetic Pickup (for the12mm nuts you will drop)





Installation involves removing the intake manifold, installing the gasket and replacing the intake manifold. Do not forget to refill the radiator once you are finished.


Note: Blocking the thermostat bypass and will stop the thermostat from opening, as the wax pellet never receives any hot water. If you choose to block the coolant bypass next to cylinder #4, you will need to remove and drill six 1/8 holes around the thermostat circumference. If you do not do this the car will overheat. Hondata gaskets do not block the coolant bypass off unless you block it off yourself, or unless otherwise noted on the gasket.




1.      It is recommended that you perform this installation on a cold engine. Drain the radiator, making sure that no animals will drink the fluid once it is drained. Remove the intake air pipe (for more maneuvering room). Next remove the fuel rail and injectors plugging the holes with rags for engine safety. Then remove the water heating pipes from the cold idle valve and idle control valve.



B16A Manifold pictured here: These will vary in location between various manifolds

2.      Remove the 12mm nuts holding the intake manifold to the head.


3.      Install the gasket making sure that all surfaces are clean and free of remnants of old gasket material.




4.      Torque the nuts to the normal factory specifications from the center of the manifold to the outside and then re-torque them after 2 hours of driving (for cars with a supercharger, torque to about 25% more since they will be inaccessible after installation is complete)



5.      Make sure all hoses and vacuum lines are reconnected to the original locations or you may experience idle problems or error codes.  On K-Series engines, it is important that the ground wire that bolts to the manifold be relocated to the top of the valve cover.


6.      Optional for slightly more cooling effect. Not all manifolds have a cold idle valve. Bypass the heater hosing for the Cold Idle valve. Cut a gasket to fit between the Cold Idle Valve and manifold and refit. Alternatively replace the Cold Idle Valve with a flat blanking plate as per the diagram. This may cause the car to idle at a lower RPM for a minute or two when starting from cold. You may need to increase your idle speed by screwing the large (7mm) screw on top of the throttle body several turns counterclockwise. Once the manifold has been pushed back disconnect the hose that runs to the idle control valve and connect to the head as shown in the diagram. Remove the cold idle control valve and install the heatshield gasket. (Above image is for a B16A, other models will vary)



H22A EGR and water flow