I've got a 318 w/ 2 1/4" duals with stock 73 318 manifolds. I'm getting ready to finish my build & am weighing the options of 340H.P. manifolds vs. traditional headers. I'm not sure that $600+ TTI headers are in my future but I may be able to pull together enough for the Hi-po manifolds or headers with a less than ideal fit. I'd appreciate some folks talking through the pros & cons of my options. Thx.