Thankyou Drdato and Lemonhead for the welcome .
SOME SPECS

All the porting and valve work on the head are done by Greg which is where a lot of horse power
is made on datsun motors. It runs 2 x 45 webers,
4 into 2 into 1 extractors, simple electronic ignition, 10:1 compression ratio, valves and springs are Greg's secret,bottom end of motor is
standard.
80% of the power is produced by the cam grind that I run, which I got when I worked for the datsun racing team in the 60's & 70's the rest of the power is from the knowledge I have learn't over the years on how to build and screw a motor together that is strong and reliable.
Anymore information would give away all the tricks of the trade and everybody would be able to build a motor with similar horse power to mine.
Thanks Greg & Kay aka vixen