I'm in the same boat with Rob2005, I'm awaiting a delivery of Berks HFC's from the group buy on here. I have a scorpion exhaust and I would like to replace the original Y pipe at the same time as the HFC's. My query would be, will these Y pipes make an outrageous noise over and above that I get from the scorpion exhaust.
Sorry if I appear to be hijacking the site, I am not, just the same issues, Cheers.