All professionals here but nobody has that information
All anyone has is intake air temp, which obviously isn't even key for most gtp owners. I'd think you could have a 4in diameter 10in long pipe mandrel bent at 22.5 degrees fabricated by any exhaust shop. Give it a couple good coats of hi temp heat reducer and go open cone. The time to figure it all out or the money it takes isn't worth it.
Only reason I was concerned is because of still got the stock air box assembley in my 98gtp and I want it to go by by.![]()