not an exhaust leak.
yeah you need the metra's gasket shims to make the metra work.
as far as points go try running with them more open then now, and then more closed....not exactly scientific but you can see if it makes a difference.
an 80 would be a tad lean on break in for the metra in my experience.
my kstar thingie was running on 16x40
i just never had the time to tune it to make it tolerable.
Im not a shitty tuner either, it is hard work to tune those little guys so they get out of thier own way. A few dudes on here will say its easy but they are either really good tuners or had someone do it for em. They arent easy.
They are easy to bolt on with a bigger pipe and go 5 mph faster.
They are not so easy to case match, and run a big carb on and tune. If i had to do it again there is no way id do it without a phbh so i could adjust the air / fuel mixture to compensate for the high revving nature of the little thing.
but i wont do it again. Maybe an athena 50cc reed or a 7 port zeta, but those little kstars just dont seem worth the agrivation to me. I get more reliability and off line torque and usable rippin mids out of a reg puch cylinder