Rather than reiterating the gist of the message I'll copy and paste this email I got from my mate Peter's pal who is a smallblock tragic in Townsville. Essentially I have the same manual as him so I'm as much in the dark as he is. If anybody has ACCURATE,(As opposed to factory supplied via 'Manglish'!) figures for spring free length and possibly seating poundage it would be a great help!
I hope you and Jude didnít get clobbered in the hail storm too badly.
I have made a small start on the assembly of the 2 monzas under the house, beginning with cylinder heads, I have measured the valve springs free length and the measurements are substantially different to the measurements in the manual I have and I have found no specs in my copy of Guzzioligy that relate to the Monza valve spring lengths. The inner valve springs I have measured (free length) are around 33.5mm for one engine and 34.5 for the other, the outer springs are 35.5 and 36.5mm respectively.
My issue is the manual has a free length of 36mm for the inner spring and 40.5mm for the outer, this seems to be too much of a discrepancy to be just rooted vale springs on both engines. I would like to know what the free length is really supposed to be as well as the loaded lengths, the manual has a couple of lengths to test at different loads which I will do when I am confident I know the correct lengths free and loaded. Also the assembled height of the valve inclusive of the spring seat/spacer to the top of the valve spring is close to 34.6mm, the manual states 37mm ! All the valves are well within the length tolerances so that is not a factor.
I would like to shim the valve springs to the correct length but I need to know what it is first, Peter and I had a look on the internet and have so far come up empty handed, if you have the correct lengths or know where to find them I would be greatly appreciative, cheers