Years ago Bob Patison from Lucas Oil told me something that has alsways stuck with me. He said "There are quite a few really good oils on the market. Use one".
Over the past 15 years I have had occasion to be inside of more motors than I care to think about. I've inspected almost-new engines, older ones that have given great service, and of course, engines that died before their time. After all of that, bob's words mean more to me now than ever. Here is what I've been taught, and what I pass along to my customers;
Use a full synthetic race oil of the viscosity reccomended by your builder. Synthec oils feature a longer-chain molecule, and this compsoition is what gives them better film strength properties. Petroleum oils will lubricate just as well as synthetics, but synthetics won't break down as quickly and when bad things do happen, you might get just that little bit of extra protection that spells the difference between a minor repair and a major overhaul. Don't pay any attention to what the top fuel cars run - remember, they only use their oil for about 4 seconds! You could use Pennzoil for that...
So what is a "good' synthetic? I have not tested them all and I'm sure that there are several great ones that I just have not worked with. But I have had very good luck with Lucas, Red Line, and the Gibbs oil. ALiSyn is also excellent if you can get it - don't know if its still being made. I've also used good 'ol Mobil 1 right off the shelf from Kragen on many occasions and will go to it in a pinch without a second thought. But for me, the best oil I've ever worked with is Royal Purple. I can tell a Royal Purple engine the second I look inside it.
Also remember, the best oil in the world wont work if its burnt or diluted. If you get the motor hot, if your fuel is off and you milk it down, if your crew chief leaves a cap off and you dump a load of dirt in there.... get that oil out.
BTW, the zinc issues as I understand it, mostly affects flat tappet engines. We have not seen any issues with the DOHC engines we work on, but for those who need help with this there are some additives that have been developed - I've heard good things about the Lucas additive - I'm sure there are others.
GOOD LUCK!
