Anyone here know if the Neo VCT cam gear unit will work on a non-neo (s1/s2) engine? Other then the front part with the anti-drag spring and access cover being different, they appear that you could swap between them? I ask because I have a s1 engine but getting a local guy to build build me one of his modified and rebuildable units, in hopes to eliminate the mechanism chatter I'm getting from heavy valve springs and larger cams. I replace my gear every season and it helps, but eventually starts to chatter again. He has a low miles NEO unit in stock already but I thought I would ask here first.