Do shorty headers make any difference what so ever in sound or tone?
Shorty headers on a stock 4.6 will offer little in terms of performances gains vs the cost/effort tradeoff of getting them on there. Additionally, though you may notice a minor difference in tone/volume it will be relatively insignificant. If you want a change in tone/volume I’d suggest getting a high-flow cat h or x pipe. The stock cats are very restrictive and adding headers while leaving the stock h-pipe is an exercise in futility. You can install an off-road h/x pipe which will be even louder, but then you’ll have to deal with emissions, MIL eliminators, and the fact that you’re polluting more (you may or may not care about this.) Long tube headers offer significant change in tone and performance but must have a matching mid-pipe installed. Installation of long tubes is a WHOLE DIFFERENT ANIMAL from installing shorties. Anyone who says different has never tried, and may have never even looked in a modular Mustang’s engine bay. If you’re set on headers, I’d go for long tubes. With a
