Would I benefit from fitting one these on a rd car.I watch something before about a Subaru tuner recommending getting one and doing away with the pcv valve.But didn't go into a std road car having one with factory power, I understand that the pcv should be changed every 30thou as part of a service

 

First, would be to check the inside of breather pipework for any residue, if dry, the head breathers probably will be, crankcase may or may not be. If dry then leave as is but if otherwise fit catch can into the existing plumbing so it acts as a filter to the standard system. No need to do away with the pcv on a road car or one that see's some track/drag.
Trev

 

I agree check the pipework for residue if oily new pipes and a can, often pipes are leaky and loose cracking, if so new pipes and if you like a can

 

He was saying that 500-600bhp is quite common now as a rd car