If you want a big performance change get old style stage 2 port and polish heads best bang for buck and easy to do. 434 bbk old stage 2 cams no lid on air box port polish head kibble white valves drz springs 175 main jet yoshi exhaust.
Just FYI, The stage 2 are the same as the old school except with an auto decomp. You'll want that. It makes life easier on your starter and and battery. I ran the old school cams for years but got tired of it being hard to turn over so I got a new stage 2 exhaust cam with the decomp. So much nicer. Also, If the topend is in good condition, wait on the bbk. Do the supporting mods for the bbk first and see what you think. Im still running on the original piston, rings, and jug and its a beast with just the supporting mods. No smoke. Perfect compression. And I run the hell out of it. I just take really good care of it. But, it also depends on what kind of riding you do. I'm all fast trail riding and hillclimbs. Set it up for what you're going to do with it. I helped my buddy build his Raptor a while back. I advised against it but he went with a 727 bbk and everything else he could do to get more power. It turned out to be useless in the trails. He couldn't keep up with my little 400. But get out on some flat straight roads or something and it would scream. Just too fast for what it was being used for. Just something to think about.
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