X2 on the 496", forged rotating assmy's for under $2000.00, Dart 320's very reasonable, no way on the 200R4 it want live unless you spend about $2,000.00 on it, go with the turbo 400. If it's in your budget go with a hydraulic roller around .660 lift. It's easy to make 600/700 HP with this combo and it can handle a 200 shot of nitrous.
JMO
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