Empi header and stinger type 1 shoots flames now?

[72blacksuper]

I got a empi header and stinger the other day and put it on last night, i don't have baffles yet and it back fires every once in a while and shoots blueish purple flames out the back like 3"-5" long it looks cool i just don't think its safe or legal. I ordered a baffle with the exhuast but it didnt come yet so i have to wait till monday. Should this fix the back firing and flames? Ohh and i want a little more power out of my bug and im thinkin about a cam, how hard are they to install and how would it change the power on a stock motor with the exhaust listed above? Im not that much of a mechanic but i put the exhuast on, i changed my own points, adjusted my valves, changed brake pads on a s-10 before, and can do a tune up pretty good on most cars. What should i do for cheap to get a little more power, i need to run 17's by the end of august so i can beet my sisters datsun 510 that runs a 17.4. Thanks for any help.

Peace,
Wil

P.S. the empi exhuast number is 3699 i think.