5mm Phenolic Intake Manifold Spacer for VW 16V Golf Corrado Scirocco Cabriolet Jetta Caddy Pickup Rabbit ABF KR PL 6A

Phenolic inlet manifold gasket acts as a barrier stopping heat transferring from the engine block through into the inlet manifold. Stopping this heat transfer results in a cooler inlet charge temperature and in doing so increases engine power in much the same way an intercooler does, except this is able to benefit a turbo and non-turbo setup.

Second picture: 2.0 16V ABF VW engine without phenolic heat shield.
Third picture: 2.0 16V ABF VW engine with phenolic heat shield.
Both pictures taken by heat camera.