I will be using the valve with a shorty header, whereas I think these were designed for stock manifolds. Will there be a problem with that?
Does anybody know if these valves are closed 100% when cold or if they are just reducing airflow? Obviously if the restriction in the crossover is alot, then the exhaust is going to blow the valve if it is closed up tight. Would be great if these things were just sort of sprung closed so if the pressure was too much, then it would allow it to open.