well i havent posted too much on here but i bought a sami about 4 weeks ago for 500 dollars but it was in peices the motor was just sitting in the bay so i pulled it the rest of the out and the put the engine back together i have a problem it sputter im not sure if it is my hommade header with nothing after that (no back pressure) or it its one of the million vacume lines i cant seem to figure out where they go so i just plugged them besides the sputter it was a very enjoyable experience

it sputter im not sure if it is my hommade header with nothing after that (no back pressure)

Nope.  Backpressure shmackpressure.  Whatever is causing the misfire, your exhaust has nothing to do with it.

well its not a missfire its a spudder at 4500 and up

carb, vacuum lines, or vacuum leak would be my guess.
download the factory service manual, or look for a diagram on the bottom side of the hood for a vacuum hose diagram that will show you where the hoses go.

thanks everyone for the help it turned out to be the spark plug wires they looked good but they were arking out by the boots