Two things,

They lowered the compression and reduced the flow in an effort to appease. It's still the same block. They can be turned to beast but you're gonna have to do a little more work. Honestly, If it's a 360 and it hasn't been messed with it ought to scoot along pretty well.

I'd worry more about the body. The power train can be done to any level you desire. New vinyl scares me.

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