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Are you talking advertised or 50 thou timing?

it would be 050 duration i'd say!

According to google xu1 has 240 at 50 and 300 advertised with 450 lift. Peak power somewhere around the 6800-7000 mark. They has a measly 10:1 comp but fuel was shit back then and so was any tuning accuracy.

General rule of thumb would say 11:1 or slightly more for that cam size in today's standards.

All cam timing I talk of is .050" duration. Depending on what XU1 cam that is mentioned, but they were all around 220 degrees except for the 1973 model which was bigger &the fuel was 98 octane Super or Avgas. The comp was 10:1 because it was a factory carthat they had to give warranty on.

Yeah I guess the warranty is a good point and probably cooling too. Those old inline 6 holden cars struggled with the rad and aero to get solid cooling. Was easy to overheat them I recall and a high comp would make it even harder to cool.

Drive faster

immortality wrote:Drive faster