Well I think I've settled on 1.39*stock maf for about perfect scaling for my car and the 3.5" maf. Ironically:
area of circle: pi*r*r
inner diameter(stock): 2.8" (r=1.4)
inner diameter(primo): 3.3" (r=1.65)
area (stock) = 1.4*1.4*3.14 = 6.15 sq inches
area (primo) = 1.65*1.65*3.14 = 8.55 sq inches
conversion ratio (primo/stock): 8.55/6.15= 1.39
Others had told me 1.5 so I went with 1.48 to start....gah.
Anyways, been playing with boost. Goal is to peak to ~26psi and hold at least 25psi at 8000rpm. It's *not* perfect, but I'm getting there
This is after about 3 revisions of testing.
(note: these pulls were started around 5000rpm, just for testing upper rpm boost...full pulls I will do when road conditions allow)
This is using my hybrid setup: hallman MBC inline with pierburg 3-port bcs. Seems to be working nicely