Bolt on Horsepower! Grimmspeed STi Thermal Manifold Spacer
Here’s an easy bolt on mod that will instantly increase the STi wheel horsepower!
For every 5 degree reduction in temperature, increases power by 1%
The Big Difference is…
When running the oem gasket only, your intake manifold gets very hot to the touch, enough to burn your hand. When the oem gasket is replaced with our Phenolic Spacer, your hand can be placed on the intake manifold without any issues.