It a bit quiet so I thought I had better say what I have been up to. Not a lot in summary, other than working on a new head for Marvin. Its a 90 Engine head, and its been skimmed a further 20 thou. The valves are standard size not super-sized, the valve seats are now blended, the valves smoother and rounded, the valve guides have new bronze inserts.
Jobs left to do, lap the valves in, clean up the inlet and exhaust ports and reassemble.
The plan is to swap off the super sized head at a later date and get the engine back to near standard and re-start the process of modification from there. The large ports and valves in the present head are great for top end power but most of the work Marvin does is off the line and pulling through the gears, low gas speed at low revs is actually holding him back (that’s the theory anyway).