I have the Kent GS2H cam in mine. Seems to give a nice extra pull.

A performance magazine did a review on cams and said the Kent GS2H gave the best results.
Edit: Here's some specs:
Application Power Band Cam Lift(mm) Valve Lift(mm) Duration Timing Full Lift VC (mm) LTDC
Sports ' R ' 2000-6500 11.32 11.32 270 Deg 25/65 65/25 110 Deg 0.00 I 1.55mm