Subject: Re: Suitable Engine Oil
I have to agree with what has been said here.
For the price of oil compared to an engine build, it is best to use as good a grade as possible. we use Duckhams/BP 20/50 or Motul 300V 20/60 on "performance" engines. But only if recently rebuilt!
Old engines as has quite rightly been said, contain a lot of sludge and "crap" and it is not always a good idea to loosen this into the engine and oil system, so a good Non Detergent oil should be used, Millers for example.
I tend to stray away from straight grades as they generally give too high pressure when cold and don't help poor old engines with corroded and frail fittings and pipework etc! Not to mention the strain on the oil pump drive!
If you have a newly rebuilt engine, this should have been meticulously cleaned and scrubbed and so should not have any sludge to "shift" what so ever, your engine does not "know" it's an old engine, it's just an engine, nothing else! so give it the best oil possible, including a detergent to stop any future sludge etc from accumulating. With today's oils there is a good range of very high tec oils available to help our engines run for many more years!
Regards,
Julian