Well guys, I know this has probably bee discussed over and over in many places before, ad nauseum, and after discussing it SOME MORE, with some of my race team, I think we may try a synthetic motor oil for the next LeMons race in the '66 Tunachucker Volvo Amazon.
My reasons for being shy of synthetics in the past were:
1) Shortly after switching to synthetic, my old '67 Imperial spun a cam bearing and broke the camshaft in half.
2) I have heard that synthetic oil tends to find leaks and exacerbate them.
3) Related to #1, I have heard that synthetics have more detergent powers, which can dislodge sludge and plug up oil passages elsewhere in the engine, causing failures.
However, I also realized that we've blown two B18 Volvo engines racing on conventional motor oils. And I have about as much proof that conventional oils killed the engines in the race car as I do that synthetics killed my old Imperial's engine. Also, the race car B20 has been rebuilt, and should be relatively sludge free. Its already been "broken in" by about 400 miles (last Fall's race), and I've heard you should not use synthetics during the break in period. And, synthetics do have advantages- especially the ability to withstand higher temperatures. Since we aren't running an oil cooler, and are using the stock radiator, this would be a big advantage.
The race is in February, which won't be so cold, but still, it'll be 14 hours of hard pounding, WOT action on the engine. I think we may use Mobil 1, 10W-30 or 10W-40, and add some of that ZDDP zinc additive for the flat tappet lifters. And of course, a new MANN oil filter.
Any other thoughts or ideas or suggestions? I had one friend tell me we should go with the 15W-50 viscosity, his logic being that even though it would create more drag and increase oil temperatures slightly, the synthetic could handle the higher temps, and the thicker oil would provide better lubrication for an older engine with looser tolerances than something more modern. Also, the thicker oil may contain more additives?
The floor's open...give me what you got!
--Mike, aka "VCH"
Captain, Tunachuckers 24 Hours of LeMons Race Team