you can port the hell out of them, or get kits. you can still run small carbs and pipes, but you won't go as fast. just figure out how to "hide" a tm24 and a destroyer, and your good.
i would think that pug would be faster, my U3 went almost 40. i got a pipe and ported mine a little tho.
25 sucks, but on the stock pipe, that's about right. u got a bigger bing on there? the 12s r slow. get a 15, and match the intake real good.
keeping them stock looking is cool, but having a performance exhaust really makes all the difference in the world. proma circuits get a solid 5mph anywhere u put them. maybe just slip the cigar's baffle cover over the stinger.