[msell44]

I was thinking of changing to synthetic oil for my 1967 330GTC. The weather has been so darn hot I thought the synthetic oil would allow the engine to run a bit cooler. It worked last summer when I converted to synthetic oil in my Porsche 356.
Any opinions if this is a good idea? I did find one reference on the Forum that synthetic oil should not be used due to seals not being compatible (but on most old car Forums, there are some guys who believe that, and the seals are fine after the change...)
So is anyone using synthetic oil? If so, what type of oil? I went to the Redline website and it suggested 5/40 weight oil but the local distributor does not carry that weight nor can he get it. If 5/40 is the correct choice, I will need to order it from Redline directly.
Thanks for the help & opinions.
Matt