Can't comment on the overhead cam but everything I've read says otherwise. VVT is just valve timing and pretty much all engine have that capability now days. I don't have to prove anything on the Ford gauges why don't you prove otherwise. I've driven many of Ford's over the years and never the seen the temp gauge regardless of slammed to the floor climbing a mountain or cruising at a steady 55. I can make the temp gauge change on the only Chevy in our fleet based on the same circumstances. Never gets close to overheating so not sure why it even matters. Buy a ScanGuage and bet you'll see temps fluctuate more than you think.