Site Information

 Loading... Please wait...
  • Image 1

GrimmSpeed Phenolic Thermal Manifold Spacer

0 Star Rating


In case you weren't aware, the cooler your intake air is the more HP your car will achieve. One way to reduce intake air temperatures is to raise the intake manifold off the engine with GrimmSpeed's Phenolic Intake-Manifold-to-Engine Thermal Spacer. Phenolic spacers have been used for years by many other specialized automotive companies, but GrimmSpeed is one of the first to offer this technology to the Subaru world.



  • Benefits/Notes:
  • Phenolic spacers greatly reduces the transfer of heat from engine to intake manifold, which reduces heat soak.
  • One of a kind true Phenolic material, not cutting board material like others.
  • Cooler intake temperature = denser air = more power.
  • Every 5° reduction in temperature increases power by 1%.
  • Direct OEM replacement.
  • 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.
  • Made in the USA
  • Available in both 3mm and 8mm thicknesses.
  • GrimmSpeed suggests using one 14035AA421 on each side of their spacer.


This product hasn't received any reviews yet. Be the first to review this product!

Write Review