im about to purchase a set of headers and h-pipe. i have a 86 5spd. im probably gonna go with an offroad h-pipe and shorty headers. my question is... are the oem headers equal length or un-equal length? and is 1 5/8" bigger than the stock size header? thanks for any input.

 

yes the 1 5/8 is bigger than the stock size which will flow better plus they aren't crimped like the stock one's and they are unequal length headers

 

sotck is unequal loke stangpower said, and if you want either equal length shorties or longtubes for the best power.