"Basicly using the 2.5 or SVT upper and lower manifolds ups the compression from 10.5 to 11.1."Is he suggesting that an SVT (ST220) manifold somehow produces a volumetric increase? effectively increasing dynamic C/R? ...like electromagnetic intake pulse charging?
Or is he confused and means 2.5
heads will up the C/R?
Or… is he full of it?

I wouldn't mind but I'm relying on this guys info on another matter so I don't want to realise I'm taking advice from a 12 year old lol