Help understanding what I'm seeing with compressor flow maps and VF turbo forum posts

[Guest]

I've seen this or something similar to this floating around the internet about VF Turbo's: http://forums.nasioc.com/forums/showthread.php?t=1141476

After much digging and searching around I finally managed to figure out that the type of TD04 I have on my V7 WRX is a TD04HL-15T with a compressor map that looks like the one in the attachment:

The compressor map has a point on it which says 428cfm and I wanted to know if this is what they mean when they quote cfm numbers on the VF turbo posts? If that's the case, then what's the point in upgrading my turbo to a VF turbo if they need more boost to flow the same air (VF29 18psi for 425cfm vs TD04HL-15T 14.7psi for 428cfm)?

A little confusing... so if anyone can help me understand this, that would be awesome.

[Guest]

Those are compressor maps not turbo maps. They dont mean all that much by themselves.

[Guest]

Dont bother with reading comp maps and comparing to internet figures and claims. A v7 with stock td04 is good for 170wkw odd at 16psi ish. A vf2/3# is good for 210-220wkw at 20psi. All ish as dynos/engines/tune/exhaust/mods etc varies and skew results.

[lachlan]

Post of the year right there