I noticed a nice difference with CTR cams. Skunk makes a good cam. Crower too. Gets a bit pricey but you can nab CTR or ITR (get 00-01 ITR cams they have same specs as CTR) cams on ebay for around 400 and as long as you dont screw with your rev limiter you dont have to upgrade the VT to use CTR/ITR cams.