Well it is getting close to that with these TF heads. I'm considering making my own valley plate so I can just run paper gaskets between the intake and the head. I haven't quite figured out how to do it yet so I'll stare at it some more.
It is possible that the bathtub is costing me some power. There is a slight bit of overhang in a few areas but it isn't much.
Have done this before but had a problem because I made it from thin Aluminium, with vibration it broke the seals on the block ends. So if your going to make one use about 1/4 ali.
