Street cruiser? Just get a set of shorty unequals. See if you can find a used pair of the discontinued Ford racing headers. I run BBK with no conplsints.
Gains? Minimal. Just one more piece of the puzzle.
street car? honestly, the stock headers are fine.
Shorty headers- maybe 5-10 hp gain.
LT headers- maybe 15-20 hp gain with reduced clearance for starters, transmission, and you need to buy a new midpipe.
Unless you are swapping heads, cam, etc... you are better off with a good cat back system and leave the stock headers on IMO..
street car? honestly, the stock headers are fine.
Shorty headers- maybe 5-10 hp gain.
LT headers- maybe 15-20 hp gain with reduced clearance for starters, transmission, and you need to buy a new midpipe.
Unless you are swapping heads, cam, etc... you are better off with a good cat back system and leave the stock headers on IMO..