Hey m8, havin problems with my message replies so will try replying here regarding the VCM9 cam (sent ya two messages but didnt go through). Anyway fuel use is the same as when i only had extractors, full exhaust, otr and mafless tune (450 km per tank). Power went from 228RWKW to 265RWKW with the cam (or 355 kw at the engine). Pulls hard and fast from idle right through the rev range with no delay at any speed. Idles nice, not too lumpy but u can tell its cammed. It will totally transform your car in response and grunt plus no need for a stally with the vcm9. My tuner also said the vcm21 is a good similar cam. With the exhaust, mafless tune, cam and now 3.73 diff gears it spins the wheels into second without trying too hard so thats pretty good for a heavy auto. No regrets with this cam for a daily driver. Hope that was a help to u. Cheers, Rob