09-12-2018, 04:20 AM
Hello
Have read conflicting things regarding the exact relationship between the 747cc Seven, 900cc Big Seven and 900cc Eight engines.
Some say the latter two are virtually clean sheet designs with little commonality between them or to the Seven engine, others say either the Big Seven or the Big Seven and Eight are both redesigns of the original Seven engine.
Also if the Eight engine does indeed share a relation stretching back to the Big Seven or Seven engines, was 900cc the maximum capacity the engine was capable of or was further stretch available (as seem to recall articles about Seven-derived engines being stretched to as much as 950cc if not more)?
And lastly is it known whether the Big Seven or Eight engines were recipients of an OHV conversion along similar lines to the LAP Head for the original Seven engine (possibly by Alta, etc)?
Have read conflicting things regarding the exact relationship between the 747cc Seven, 900cc Big Seven and 900cc Eight engines.
Some say the latter two are virtually clean sheet designs with little commonality between them or to the Seven engine, others say either the Big Seven or the Big Seven and Eight are both redesigns of the original Seven engine.
Also if the Eight engine does indeed share a relation stretching back to the Big Seven or Seven engines, was 900cc the maximum capacity the engine was capable of or was further stretch available (as seem to recall articles about Seven-derived engines being stretched to as much as 950cc if not more)?
And lastly is it known whether the Big Seven or Eight engines were recipients of an OHV conversion along similar lines to the LAP Head for the original Seven engine (possibly by Alta, etc)?