Solidus311

My rb was dyno tuned with stock everything except a custom front mount kit, greddy intake plenum and a walbro pump. The fuel was turned down like 20% by an SAFC but is still running rich.

I heard that a fuel pressure regulator would remedy my problem. I was going to opt for a nismo regulator but I wanted to know what the correct pressure was. Am I supposed to make it a certain psi while idling and driving? Or just idling? I will probably get an AEM wideband before anything else. Thanks.