head pipe

I have a 87 250x with a white brothers pro meg with a web all around cam, 11 to 1 aries piston ultra lite, bored 80 over, K and N filer and air box mods, 20 inch razor rears, stock gearing, is fairly fast will beat warriors with the same mods. WOuld it be worth the money to buy and after market head pipe? How much of an increase would I notice? WOuld I benefit from a 14 tooth front sprocket?

Thanks