mustangsavage1967

Im using 10 - 30 right now but what about synthetic oil? The engine is rebuilt but i was always under the impression synthetic oil was for more modern cars and no classics. Is it possible to use synthetics and are they better? Would it help lubricate my rocker arms and lifters better? Just looking for some opinions Thanks all

Oxnard Montalvo

There are a gazillion articles with a gazillion different conclusions about this issue.
For me the cliff notes are that yes, synthetic can be used in older cars and if nothing else it lasts longer, and that the only motors that have any problem with the reduced zinc in todays oils are motors with high lift cams and heavy valve springs. If you get nervous you can and zinc... But too much zinc is bad... It goes on and on.

PaulS

Since the materials used in our engines has not undergone any fundamental change and the purpose of oil is stil to clean lube and cool it would seem to me that synthetic oils would have no detrimental effects on older engines. all oils for cars use about the same amount of zinc so during your break-in period use an additive or an oil that is higher in zinc.

mr_velocity

The biggest advantage to synthetic is how it performs when something goes terribly wrong. I punched a whole in the head of one of my big blocks, ran nearly an hour with coolant dumping into the cylinder. When I pulled the motor apart, although the oil was a milk shake, every bearing surface, every lifter, every rocker, every cylinder wall was perfect. All the motor needed was a new head.
I've also seen much cooler oil temps between M1 and Redline, as much as 25 degrees under the exact same conditions. Same weight, same motor, same ambient temp.

For me the question has a simple answer, how much is a little extra insurance worth?
Personally I run Redline in everything from the lawn mower to my high dollar big blocks.

Oxnard Montalvo

Fixed.

67mustang302

I run fully synthetic Torco 10-40 in mine, prolly gonna switch to 20-50 next change just due to the abuse factor I place on my engine.

I recently had the heads off to replace a blown gasket....with close to 250k miles on the engine, the only wear it has was a worn valve guide from when a rocker rattled loose previously. Otherwise, everything was good and the cylinders looked brand new.

urban_cowboy

I use Valvoline VR1 mostly because it is a race oil so it still has all the good stuff in it. It comes in both solid weight and multiweight. I run the 20W-50 in my 383. I also hear good things about Royal Purple but have not investigated them. Comp Cams has a new muscle car oil out, but their website is so crummy, good luck finding it.

mr_velocity

I haven't done too much research on Valvoline but be very careful with any "race" oils since many of them don't contain detergent packages or contain very low levels of detergents.

From what I understand there are 2 versions of VR1, one has detergents and one doesn't. The one that doesn't is marked "not for street use". I wouldn't have a problem running VR1, it's a good oil with lots (not up to date info) of ZDDP. Been a while since I've been down the oil research path since I've become loyal to one brand.

stephen.osborne1

I have been running Motorcraft 10-30 semi synthetic ever since my third oil change with positive results. My 2cents

rmodel65

holy huge sig/\