I wanted to share the results I got with a cylinder head up grade. The changes I made were to replace the TF 240 heads with TF 270's. Using the TF 270 matching large port intake and to install a carb base plate with a dual pattern so as to fit the dominator flange intake. Also installed adaptor / shear plate under the carb. {AR engineering part. thank you BradH ! ] . I've raced the car several times and the end result is car went from mid 10.70's avg to mid 10.50's avg. My best pass with the new heads so far is a 10.48 at 128.77. in ok weather. The changes have not quite gotten me where I want to be , which is to be able a 10.50 index in summer weather. My 60' times are still soft with 1.49 to 1.51 times. Are my results what you would expect ? I was expecting better.