If you know anybody into small block Ford racing. I have a set of new in the box assembled Trick Flow "R" heads for sale. Have raised exhaust ports. Part # is 52400100 and the serial #'s are 4971 and 4972 for each head. Will make 600hp plus on a 427 small block on pump gas. Some of the SBF turbo guys are making 1300hp plus with these heads. I have had them for three years and decided to stick with the big block stuff. New and never bolted to a engine. I will trade for a 521 rotating assembly depending on what it includes. For sale price is $1300 plus shipping for the heads. They are $1700 new from Summit Racing. Email or pm any ?'s.