oil

looked again in the archives for oil. My sources for valoline 50 wt racing oil are drying up. Can I use a synthetic ie. mobil one 20-50 or should I stay with the 50wt. I have changed to synyhetic in all my cars, with great results. however I'm not sure due to the multi weight if it will work safely. any suggestions will help. last post about gas shut off valve. when mixed gas and oil. which floats? I really don't want gas in my oil.

My 46 FL engine may be clearenced diferently but I run 20-50 in Georgia. It works fine here.
F

thanks fh, I'm reasonably sure I had heard that multi grade oil worked well. But the 50wt feels so much thicker. the motor is 5 years fresh with about 3k to 4k on it. I trust the builder very much. I'm sure all the tolerances are to spec. I should have asked at the same time, how about the trans. Rebuilt by the same guy. will 20-50 work there too?

Any shop who does business with Custom Chrome can get 50WT for you. Buy it by the case so it will always be handy.

I run 20/50 semi synth in my '40 knuck. Runs fine. I tried 50wt but it ran noticably hotter. For my trans (4 speed) I like that Valvoline 75/90 semi synth gear oil. Makes it shift really smooth. I also tried Mobil 1 75/90 straight synth, but couldn't stop that stuff from leaking.

I finally made the switch to 20-50 3 yrs ago, maintains the same oil pressure as straight 50. And, seems to stay inside just as good as the straight 50 did
DD

Do you think the 20-50 would hold up to the constant heat here in Florida?

I put pressure gauges on both flatties, and the pressure readings didn't change when I made the switchover. Now, we don't always run 90+ temps in the Summer, but we get enough to make data runs The 20-50 does as advertised. Has the viscosity of 50 weight when hot. Believe me, I was a skeptic, I've been running 50 or 60 weight since I was a pup.
DD

Thanks Doc, seems to be getting harder an harder to get straight weight oil here every year. I'm running 10-40 in my 63 an 67 Fords now for a week, I just got tired of running around looking and begging parts men to order oil by the case.

Neil74,
I'll bet that those old Fords would prefer a nice 15-40 Diesel oil. It still has lots of ZDDP even the Low Emissions 15-40s still have 1100 to 1200 PPM ZDDP. The neighbors 428 ate a cam lobe shortly after they took the ZDDP out of regular motor oil. It seems to be fine this time with Delo 15-40.
Dusty

[Pa]

Try your local farm tractor supply or farm tractor repair shop. Pa

Thanks I'll look into the 15-40, funny when living in the country the farm stores the first place you look an when living in town the last. Thanks for the kick in the pants Pa, I should have looked there first:)