Have 67 SS Chevelle 396 TH400 etc. Currently in paint. Fixing and upgrading countless other areas. One question i need answered...Need info on headers for my application. Temp coated, 3" collector,1 7/8" primary. Eng. is street/strip as was turned 13.0 with a big bog at the line. Beleived to have fixed bog. Pics. to follow when i figure out how to.