IAG Performance 3mm Phenolic Spacer KitIAG Performance is proud to offer 3mm phenolic grade CE spacers for your 2. 0L and 2. 5L engine. This is a simple, cost effective way to maximize the power of your current set up. The 3mm spacer is thick enough to provide superior thermal insulation to the factory steel gasket but thin enough to avoid clearance issues that can arise with the 8mm spacer Why it works: The concept behind the phenolic spacer is simple: isolate the heat produced by the