Updated....
1957 Maserati 3500 GT Frua Spyder
A one-off example by Frua, a car I've never seen before but one can definitely see outlines of the future AC 428....
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Also many more pictures....
http://www.pietro-frua.de/1959_maserati.htm _______________________
1957 Maserati 3500GT Frua Spyder
Chassis Number: AM101.268
One-Off Example!
The 3500 GT debuted at the Geneva show in March 1957 and it would be the first real series-produced Maserati, remaining in production through several generations and model names until 1970. Its twin-plug ignition immediately betrayed the racing origin of this high performance six although it was completely redesigned, in fact twice, to make it both more easily maintainable by non-racing mechanics and more economical to build.
The dual overhead camshafts operated the valves through bucket followers with shim adjustment in preference to the screw-type adjustment favored on the racing engines. Both the cylinder block and the head were cast in light alloy with iron cylinder sleeves. Seven main bearings ensured reliability. This 1957 Maserati Frua Spider was purchased by Mr. Alfredo Brener’s collection of exceptional Maseratis several years ago. It had been restored in Britain for a previous owner in its original color of light yellow and retains its original green interior.
http://autocollections.com/index.cfm?id=143&action=details&tab=inventory&cartable=&sortorder=car,year&sr=46 
With Grateful Acknowledgements
