MACE PERFORMANCE MANIFOLD INSULATOR TO SUIT HOLDEN CREWMAN VZ ALLOYTEC LE0 3.6L V6Exclusive to Mace Engineering, here we have our design registered lower manifold insulators to suit the Holden VZ and VE series, fitted with an Alloytec 3. 6L V6. What are manifold insulators and what do they do? Manifold insulators are a thermal insulating spacer that mount betweenyour engine block and intake manifold. Made from a heat blocking composite, our manifold insulators will increase power from your engine by keeping the intake cooler and