what your opinion on millers high synthetic 10w40 an dthe cfs 10w60.
i'm running a zvh with a cossie 4wd turbo and around 20psi of boost.
i have an oil coller too on a thermostatic sandwich block.

high synthetic 10w40 is what i'm using at the moment (less than £20 a bottle from motorfactors with a little discount too)