I see a lot of sohcs using this, does it flow
Enough to gain usable power on a b18c1?

 

Not really. Expecially not for the RPM range of the GSR.

 

LOL a td04 is what they use on wrx and dsm's... people use them because they are cheap and everywhere...

You get spool almost sitting still but run out of steam at like 4K rpm and then you start going slower... On my WRX I switched the TDO4 out the week I bought it and put a Large 16g just so I could have some top end...

The exhause side of tdo4 is only like 2 inches I beleave, it will choke your Gsr quick, say good by to your red line

 

No tdo5 is what Dsms use, and vf is subie, but still don't waste your time

 

TD04 is in fact subaru. WRX is 04, STi VF series. and TD05's as well on Subaru, more along the JDM line.

 

VF** is the name.. size is tdo4

 

I guess you are right about the subie, I think you are right about the td04 I think 14b/16g are tdo4's and 18g/20g are tdo5/h