you didn't get this from the full throttle tv show did you?
first off you have headers, not a manifold. 2ndly the headers you have will work fine unless you are moving tons of air. so unless you have a big turbo, and reworked heads i wouldnt' even concider headers. the small tube headers you have now ARE good. if there cracked, spray all the bolts down with wd-40 every day for about a week, then take the bolts out, the headers should come out pretty easly form the bottom (never played with a hot air car, just ASSuming its similar to a ic car) and have them welded. reverse the process to get them back in.
