dba

Does high oil useage denote mechanical deficiencies,does high oil useage reduce power,why,what,how!!!

like specifically,why do Alfa twin sparks use oil,and Imprezas don't?

Steve vRS

Best answer I can give until someone more knowledgeable steps in is that all engines are different. This is due to a number of factors and starts with how the engine leaves the factory.

Each engine component is built to a tolerance (= or - 0.05mm for example). SO on average once all the components are assembled, the engine will be average. You may get a looser or a tighter engine depending on how the tolerances built up along the assembly process.

Perhaps an Alfa's tolerances are wider than a Subaru's?

The other factor is wear. The more an engine is worn, the wider the gaps between for example the piston rings and the engine bore get so oil is lost that way.

Steve "Standing to be corrected" Sherwen

mutant_matt

I think some of it is down to how it's run in. If you run it in hard then it will be looser, will burn more oil and will not last as long but will produce more power. If you run it in carefully and gently, it will be tighter and burn less oil and will last longer and be slower......

Of course, if there is something wrong with it (worn rings/bores/valve seals) then it will burn a lot more also.

Matt