[vw911]

2.0L 914 heads are 42x36. You can use T4 heads rework them and get the performance you are looking for. 914 heads cost so much because they have sodium filled valves in them and the construction of the heads. You can put 44x40, 46x42, or 48x44 valves in your car ported and polished on T4 heads and get the performance.