I got my head reconditioned and by looking at another rb30 head i can see that there is a fair bit of difference between the two..as in how much has been machined of the face, the head has proberly been machined a couple times and i was just wondering if this will cause issues like to much compression or possible engine damage? should i get a decompression plate? thanks

Its hard to say. Whenever you get the head faced - which shouldnt be often, then record the amount taken off... A small amount taken off is over a large area so it does affect CR. The VLT has more valve lift but lower CR pistons, I wouldnt want more than 1mm absolute max taken off the VLT one purely for the issue of valve clearance. Many people are running VL n/a with a turbo and seem not to experience much if any CR related detonation or pinging so if its on your n/a one then maybe max of 2mm... (maybe)... But seriously you would need to get it checked, the figures I have quoted above are a guess at most from what I have seen on other engines, so dont take my word for it - get it checked re valve clearance and that means to allow for things like valve bounce etc, ie If new valves then prob ok, if old valves a static clearance might be ok but not when revving to 6000 rpms Ive had heads off and only ever given them a cursory clean, not had them faced, hardly worth it unless they are warped, the gasket does tend to take up quite a bit - esp if you can smear some appropriate sealant (thinl) on both sides of the gasket *and* retorque the head after approx 1000kms runin...