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* Sept WCS trades at $14.65/bbl below WTI
By Nia Williams
CALGARY, Alberta, Aug 25 (Reuters) - Canadian heavy crudedifferentials tightened on Tuesday after BP Plc restarteda crude unit at its 413,500 barrel-per-day Whiting, Indiana,refinery weeks earlier than initially expected.
BP said production at Whiting, one of the largest consumersof Canadian crude in the Midwest, would return to normal levelsin the coming days, boosting demand for heavy crude.
Western Canada Select heavy blend crude for Septemberdelivery last traded at $14.65 per barrel below the West TexasIntermediate benchmark, tightening from $15.50 per barrel belowWTI on Monday, according to Shorcan Energy brokers.
Differentials blew out to their widest level in a year whennews of the malfunction at Whiting's largest crude unit,combined with outages on two key Enbridge Inc pipelines, reached the market just over two weeks ago.
The earlier-than-expected restart provides some relief toCanadian crude producers who are struggling with a global cruderout that dragged the outright price of WCS close to $20 lastweek.
Outright WCS last traded at around $24.66 a barrel.
There was no trade in light synthetic crude from the oilsands for September delivery, according to Shorcan.
The Canadian crude market is outside the nearlythree-week-long trading "window" - from the first of each monthuntil the day before pipeline nominations are due - in which thebulk of activity takes place. (Editing by Alan Crosby)
