I would stay away from header wrap. From what I have read it tends to hold moisture, which tends to rust the pipes. I had my new in 2001 pph headers...
I watched Engine Masters, thermal wrap made zero HP, same engine/same headers on the dyno. I only ask because I wanted to reduce my under hood heat,...
I have seen this happen but to my SS/E 428 Mustang about a thousand years ago. Best in that car was a 10.99 w a 6000 rpm hole shot (stick shift) and...