My VR pulled 184bhp on the Docs DD rolling road with just a de-cat and im pretty sure them rollers are as god as any when it comes to accuracy. I now have the 2.9 obd1 plenum with port matched and polished tb so I reckon I wont be far off 200bhp now.
With not a great deal of work, you can get passed the 200bhp mark with a VR (Cams), however it will never handle aswell as a Valver, thats a certainty