anak_liar, to fabricate your own downpipe (I'm assuming you are talking about exhaust headers), you need welding equipment, tubing benders and some other misc stuff. Unless you want to experiment with different downpipe configurations, it's wiser to get a premade one to save on all the hassle.
I've finally eaten enough maggi to save up for pistons and con rod(bought already). Hair also falling off already. with that, wanna ask the speed demons here what's the best or most practical solution for a set of...