Can also verify with a non-running engine by turning the cam by hand and verifying which direction that lifter spins/ if it spins at all.
I am more than glad to be mistaken but does synthetic oil not have a higher burning temperature than conventional oil? If so, then I would think one reason for synthetics would be to prevent oil coking. I know this was a problem in the 80's but seems to be non-existant on todays turbo engines when run with even semi-synthetic oil or full synthetic, ie Ecoboost Fords. Any thoughts or experience seeing turbo failures on high mileage cars? I still change my synthetic oil often but I believe there is at least some benefit, but again, I'd be glad to be wrong about this to save some $. I know my oil pressure is higher with synthetic during the summer months vs conventional (Brad Penn vs Amsoil for me) so that leads me to believe that synthetics are at least more stable with pressure and flow over a wider range of operating temperatures... And all factory Ford oil, followed recently by GM EOS, and soon to be Chrysler Corp, all have at least semi-synthetic oil as standard equipment and standard replacement. If the OEM's are going that direction, then I'd think there is an engineer somewhere saying that it's needed, at least for the extended intervals they push now a days. I'm not saying conventional oil changed frequently won't protect a TR motor, and you are an expert and I am far from that, but to say there is NO benefit to synthetic seems to be too broad of a statement. I await my education and thanks as always for everything you do for the community, Nick. And what are some of the "numerous reasons besides price" to NOT use it?
Problem is most likely high lift cams and stiff springs. Stick with ZDDP, Comp springs that are recommended and nothing too steep on the cam. Running 208/208 myself.
I'm with Nick on the synth thing. What a waste. You asked about experiences with high mileage cars and turbo failures. I can add my experience since I own two high mileage GN's that I've owned for over 20 years, on for over 25. The 86 (my original) in on it's second turbo. Upgraded from the stocker to its present TE44 way back in the very early 90's. I've never used synth oil and never will. Coking?? Another myth with modern oils (non synth). If I had to guess I'd say this turbo has well in excess of 50,000 very hard miles including countless trips down the drag strip and it seems to have suffered NO ill effects and is still going strong! My 87 was also an early 90's upgrade from stock to a TA49. It was the ONLY turbo failure I've ever suffered, and was not due to an oiling issue but rather a chunk of Champion spark plug ripping through the tubine!! Regular oil changes every 5,000 miles and good high quality filters are all that these two have ever seen. Both still going like gang busters, and no need for synths. Just good dyno oil and zddp. Overly aggressive cams and springs that are just too heavy are what kills the flat tapped cams going into these cars!!!!! Geezz, even my 87 is still on it's original everyting (including cam lifters and springs) at 135,000 miles. Still pulls hard all the way to it's 5,000 rpm shift point. This valve sping mania that everbody suffers is also a myth. I believe this strongly enough that the original block that I'm putting back together for my 86 is going to have a mild 202/202 cam and STOCK rated springs.
Excellent. That's what I was looking for. Pretty sure I'll be making the switch back, with zddp still though. And I used 75lb valvesprings from TA when I did my cam and it pulls very well, even past 5k rpm, but I don't take it much past. I'm running an Erson 208/208 straight up and and down and probably should have went with less cam. Heads are port matched and that's it.
