Is there a big difference between your 12mm and 25mm manifold spacers for Alloytec VE? Will it fit my car g8?

The 12mm and 25mm manifold insulators for the Alloytec (LY7) engine, increase torque by 10% and 13% respectively. If you tend to spend most of your time in the mid to top end range or low to mid range, then we would recommend the 12mm and 25mm manifold insulators respectively and it will fit your car.