im told by prev owen he put a recirc valve on and it didnt run so good so he put the atmopheric one on.... ive removed it as i read on here its not good for it, but then maybe if car was mapped it would explain why it runs better with the atmopheric, wud i be able to tell if it wasnt good if i fitted it?
What I meant was that, if your car was mapped to run an atmospheric dump valve then it's fine, I do not mean if it's mapped then it's fine.
Your picture shows that your car still has a mass air flow sensor so clearly it's not mapped to run off a table with only manifold absolute pressure sensor and revs, so your car was mapped to run recirculating only! It's easy for the previous owner of the car to so easily dismiss your questions with "o I did have a recirculating diverter valve but it runs better on atmospheric"
Very likely his recirculating diverter valve spring was the original green one which was likely weak to begin with anyway! Combined with the extra boost after remap it was probably not holding boost. Whereas the atmospheric dump valve was new and probably had a stiffer spring. Clearly he misconstrued this as the solution.