Best Oil

[jaybale23]

What is the best oil recommended for a 351c 1972 Mach 1. I have been using an advanced engine oil high mileage full synthetic 5w-30. Is this the proper oil?

 

[MAD IRISHMAN]

Boy is this opening a Pandora's box of recommendations, opinions, and bulls#*t! LOL

Probably need to give more details like mileage on engine or run time. Flat tappet lifters (solid or hydraulic) or roller lifters.
Currently I'm using Lucas Hot Rod 5W-30 in mine. Although I use synthetics in about everything else, I don't get out much, so not needed.
But that's me.

 

[jaybale23]

Haha. Thanks for the warning. Mileage is over 100k. Not sure about lifters. Oil change is the extent of my mechanical skills. So sounds like 5w-30 from mobile 1 is acceptable. Just wanted to make sure I won’t blow up my engine.

 

[Ron Tanzi]

What is the best oil recommended for a 351c 1972 Mach 1. I have been using an advanced engine oil high mileage full synthetic 5w-30. Is this the proper oil?

That is a bit on the lighter side of oils for a Cleveland. I would not be using 5w-30. I use Brad Penn 20w-50. It has all the additives needed to protect your cam. I use my car in warm weather and it lives in a heated garage hence the 20w-50.

Ron

 

[Steed73]

The new oils have less zinc in them and that can damage older model engines. You need an oil with high zinc content or you can use synthetics

 

[Ryunker]

What is the best oil recommended for a 351c 1972 Mach 1. I have been using an advanced engine oil high mileage full synthetic 5w-30. Is this the proper oil?

Many opinions, everyone has them.

I use the Valvoline VR1 20w50, old design of engines were never designed to run on current thin oils.

Mind you I run full synthetic in everything else, big fan of them.

The thicker oil with the forementioned zinc is recommended, the old engines are very heavy, all pieces in there are also heavy, my belief if the 20w50 acts some of a "shock absorber" for the rod bearings as well.

 

[basstrix]

In my opinion, to determine what the "best" is of just about anything, "best" must be clearly defined. There are many suitable options, but doubtful that a rigorous battery of tests has been done to distinguish one from the rest. Throw in the lack of a clear root-cause for the high rate of cam/lifter failures over the last few years and "best" becomes even more unclear.

For flat tappet cammed engines, I use Valvoline VR-1 Racing in conventional formulation. Valvoline has a good reputation and the conventional Racing formula has a high level of zinc....just in case that IS the root cause for the cam/lifter failures. For rollers, my truck runs Rotella and the car runs Mobil 1.

 

[jdj327]

Amsoil Z rod 10w 30, this oil is designed for our older engines. You will want an oil with zinc in it. Don't do the zinc additive, you want an oil formulated to keep it in suspension.

 

[Spike Morelli]

This is what is in your Owner’s Manual: When outside “Temp Is Constant”-

Multi-viscosity Oils -

Below 32F degrees, 5w-30

10F to 90F, 10w-30

Above +32F degrees, 10w-40 or 20w-40



Single Viscosity Oils –

-10F to +32 F degrees, 10w

+10F to +60F degrees, 20w- 20

+32F to +90F degrees, 30w

Above 60Fdegrees, 40w

The Ford manual recommends to change oil every 6 months or 6000 miles. I use Valvoline VR-1 Racing Oil. It has been a standard of the industry for performance oils as long as I can remember. Of course, I use it, not that I think my Mustang is a "race car", but because it has the required amounts of "ZDDP", ( zinc), for our flat tappet engines. I use it in my roller cammed engines as well because it is a high quality oil, ashless, and has the anti-foaming aspect.

Besides all that, I feel quite comfortable with a straight 30 Racing in my every day, street clearanced 351c, car. An engine running larger racing clearances may benefit by using a next higher viscosity oil. My Blown/Injected Hemi drag boat, for instance, uses Valvoline Racing 50, but obviously has looser rod and main, as well as rod-to-rod side clearances, so a higher viscosity is appropriate here.

 

[turtle5353]

15w-40 Rotella. Has all the good stuff in it

 

[Ron Tanzi]

From what I have read Shell's Rotella oils have been cutting back if not totally removed by now most of the zinc in their oils. Due their effect on modern diesel emission systems. It is all about those dang emissions.

Ron

 

[mrgmhale]

Boy is this opening a Pandora's box of recommendations, opinions, and bulls#*t! LOL

Probably need to give more details like mileage on engine or run time. Flat tappet lifters (solid or hydraulic) or roller lifters.
Currently I'm using Lucas Hot Rod 5W-30 in mine. Although I use synthetics in about everything else, I don't get out much, so not needed.
But that's me.

Mad Irishman is so correct. Jaybale23 definitely opened up a can of worms with his inquiry. But, as luck would have it, there are no really bad answers, mostly because engine oils overall have become quite refined with their protective abilities as compared to oils from as recently as the 60s and 70s. And, opinions exist aplenty, to include my own thoughts. Of course, I feel my opinions have some credible backing as I have made a sincere effort to form an opinion based on original engine oil requirements from the vehicle manufacturer, and based on my own evaluations when reviewing research results from several credible sources. So, following I offer my thoughts on the matter.

The engine oil weight recommended by Ford for a particular year and engine size is what I tend to follow. For our 68 Shelby GT500 with its phenomenal 428CJ engine I use a 10/30 weight oil. The 351W (not C) engine in our 1973 Mach 1 came out of a 1994 F-150, and was built to a moderate street/street degree, resulting in a spirited 360HP at the crankshaft - enough to keep things thrilling, especially with its 3.5:1 TractionLok rear axle gear set and the transplanted 4 speed AOD tranny. The engine rebuilder apparently recommended 10/30 oil for it (just like the Shelby), so as with the GT500, I have been using 10/30 for the Mach 1 also. The same goes for our 1973 Mustang Convertible and its bone stock 302 2v engine, 10/30. But... In the event any of the engine were to begin to use or burn oil due to the engine getting worn I will move to a 20/40 (or 10/40) weight oil right away. And once that 20/40 oil begins to get used/burned "too quickly," I will have my excuse, er, I mean, reason for rebuilding the engine with the alleged problem. And, of course, I will be rebuilding the affected engine in a way that it will have superior performance and longevity issues addressed from the inside out. For me (getting off track a little, sorry) that would include moving to a roller hydraulic valve train design, inserting bronze wall valve guides, using single piece, high quality intake and exhaust valves, aluminum alloy high performance pistons and high performance connecting rods, hardened valve seats, Perfect Circle "real" valve guide seals as opposed to the upside umbrella oil splash diverter excuse for a seal from the factory design, dual roller timing chain, and timing gears that are all metal (no nylon/plastic tips on the cam gear teeth). Okay, back to the main subject in this thread now...

The next hurdle to deal with is deciding between petroleum based and synthetic oils. For me, the decision was an easy one. Synthetic engine oils outperform petroleum based engine oils - hands down in all categories other than price per volume. I dare say there really is no competition between petroleum and synthetic oils. And, although the petroleum oils are less per any given volume, the synthetic oils offer a greater value, period - no qualifying statements needed. That said, a high quality petroleum oil that includes the various additives in its blend for any particular purpose is going to be a good choice, although the synthetic oils will still beat the petroleum oils in every performance category.

Alas, there are two things to consider when dealing with synthetic oil (I am purposely ignoring the cost of synthetic oils, as for me I will pay what I must for the best products available). One is the pervasive claim/belief that synthetic oils will cause engine oil leaks to occur. I will not mock that assertion as being totally inaccurate, as there is plenty of anecdotal "evidence" that synthetic oils will cause leaks to appear where once there was no leaking. In my reading on that subject it comes down to this. Synthetic oils do not "cause" engine oil leakage. Rather, they create a situation that "allows" leaks to occur. So, what looks at first like an ambiguity at best, and weasel wording at worst, can be explained rather simply. Synthetic oils have superior cleansing additives that tend to get rid of the very materials that may otherwise (with petroleum based oil) be present in sufficient quantity to hide or obscure oil leaks that would otherwise be occurring, So, conditions that would otherwise allow for a leak are masked because petroleum based oils do not clean deeply enough to let the oil leak occur. The synthetic oil additives, doing their superior job, will clean up those issues not handled by petroleum based oils, and a leak may appear.

So, it is not the synthetic oil that causes the leaks, when they occur. It is more that the leak condition already existed, but the petroleum oils did not keep things so clean that the actual leak ever began. Is the synthetic oil responsible for the leak? No. But, did it allow the leak to occur once it cleaned away the residue missed by the petroleum oil, well, yeah - that it did. Therefore, the synthetic oil is blamed for the leak, as opposed to being cheered for doing such a good job getting things cleaned up. Sadly, reverting back to petroleum oil will likely not "fix" the leak as the residue that once kept the leak from becoming evident is already gone. I get how frustrating this can be for someone who has switched to synthetic oil, where the synthetic only made it clear there is a sealing issue simply by cleaning things up so well. Personally, I would not have been very happy if a leak, much less a rear main seal leak (for example), were to start after moving to a synthetic oil. In fact, I may even be angry enough to be tempted to other folks to not use synthetic oil as it causes leaks - other than the fact that I know why this happens at times (not in all cases), and I also recognize all the massive benefit synthetic oil brings to the table. I would, instead, roll up my sleeves and get on with correcting a condition I would not have seen otherwise.

The other issue is one that I cry out about every chance I get. And, I was very pleased to see was clearly addressed in this thread by Steed73, and mentioned by a few other folks as well. The older, flat tappet engines used in First Generation Mustangs and Shelbys, need Zinc, or actually Zinc and Phosphate, in their engine oil. Most modern engine oil no longer has Zinc in it. The reason is because it turns out Zinc fouls catalytic converters. So, in correcting a problem with Zinc for newer, catalytic converter based cars, the oil manufacturers have caused a potential problem for older engines - namely a lack of Zinc that will result in excessively and badly worn camshaft lobes, and lifter faces. The situation is one where anyone with old school flat tappet engines needs to make certain their engine oil has Zinc in it, or they need to use a Zinc additive. For older engine that are rebuilt and fit with a roller hydraulic valve train, as opposed to keeping the old school flat tappet valve train design, Zinc is not needed. But, it does not hurt for it to be present as our pre-74 vehicles were not equipped with catalytic converters.

Now, finally, we get to the place where I give my sworn testimony re: which oil is "best." Right out the gate I will confess this is both my opinion, and meant in the context of the vintage vehicles Lynda and I have, and how we drive them. And, I will provide my reason(a) for why I have chosen as I have. But first, we have gotten to the point with automotive engine oil where I can say there really is no "bad" oil. There may be incorrect weights and/or additive choices based on certain factors (flat tappet valve trains vs hydraulic roller valve trains, environmental temperature, intended use of the engine, etc.). So, here it is. For our 1969 Shelby and 1973 Mustangs I use AmsOil Z-Rod 10/30 oil (https://www.amsoil.com/p/z-rod-10w-30-synthetic-motor-oil-zrt/). It is the correct viscosity (10/30) per engine builder/vehicle manufacturer, has the Zinc needed for the old school flat tappet valve train design of their engines, and in some really well designed tests has been proven to be the very best of the best of engine oils (of the best). Some of the more recent, really good tests I have seen ware performed by Project Farm (YouTube Channel name). I find the guy who presents the tests on the Project Farm videos does a terrific job - matching the quality and extent of the tests run on a lot of different things (I tend to watch his videos on car parts, oils, and automotive tools - check his channel out, I am a raving fan). The Project Farm video re: oil comparisons that involve AmsOil Z-Rod are at the following links:

https://www.youtube.com/watch?v=TWuKvnCq1js

https://www.youtube.com/watch?v=E2zS8MyvJxU

https://www.youtube.com/watch?v=rPLrknPf3Do

Okay, I now rest my case... YMMV

 

[LloydB]

Flat tappet cams = high zinc oil or whatever oil you choose plus a zinc additive. I emailed every camshaft manufacture I found online, they all said "Hi-Zinc is required" and then a random brand name OR zinc additive of your choice. Brand, weight and source of purchase are based on your personal preference with guidance from your engine manufacture.

 

[jaybale23]

Mad Irishman is so correct. Jaybale23 definitely opened up a can of worms with his inquiry. But, as luck would have it, there are no really bad answers, mostly because engine oils overall have become quite refined with their protective abilities as compared to oils from as recently as the 60s and 70s. And, opinions exist aplenty, to include my own thoughts. Of course, I feel my opinions have some credible backing as I have made a sincere effort to form an opinion based on original engine oil requirements from the vehicle manufacturer, and based on my own evaluations when reviewing research results from several credible sources. So, following I offer my thoughts on the matter.

The engine oil weight recommended by Ford for a particular year and engine size is what I tend to follow. For our 68 Shelby GT500 with its phenomenal 438CJ engine I use a 10/30 weight oil. The 351W (not C) engine in our 1973 Mach 1 came out of a 1994 F-150, and was built to a moderate street/street degree, resulting in a spirited 360HP at the crankshaft - enough to keep things thrilling, especially with its 3.5:1 TractionLok rear axle gear set and the transplanted 4 speed AOD tranny. The engine rebuilder apparently recommended 10/30 oil for it (just like the Shelby), so as with the GT500, I have been using 10/30 for the Mach 1 also. The same goes for our 1973 Mustang Convertible and its bone stock 302 2v engine, 10/30. But... In the event any of the engine were to begin to use or burn oil due to the engine getting worn I will move to a 20/40 weight oil right away. And once that 20/40 oil begins to get used/burned "too quickly," I will have my excuse, er, I mean, reason for rebuilding the engine with the alleged problem. And, of course, I will be rebuilding the affected engine in a way that it will have superior performance and longevity issues addressed from the inside out. For me (getting off track a little, sorry) that would include moving to a roller hydraulic valve train design, inserting bronze wall valve guides, using single piece, high quality intake and exhaust valves, aluminum alloy high performance pistons and high performance connecting rods, hardened valve seats, Perfect Circle "real" valve guide seals as opposed to the upside umbrella oil splash diverter excuse for a seal from the factory design, dual roller timing chain, and timing gears that are all metal (no nylon/plastic tips on the cam gear teeth). Okay, back to the main subject in this thread now...

The next hurdle to deal with is deciding between petroleum based and synthetic oils. For me, the decision was an easy one. Synthetic engine oils outperform petroleum based engine oils - hands down in all categories other than price per volume. I dare say there really is no competition between petroleum and synthetic oils. And, although the petroleum oils are less pr any given volume, the synthetic oils offer a greater value, period -no qualifying statements needed. That said, a high quality petroleum oil that incldues the various additives in its blend for any particular purpose is going to be a good choice, although the synthetic oils will still beat the petroleum oils in every performance category.

Alas, there are two things to consider when dealing with synthetic oil (I am purposely ignoring the cost of synthetic oils, as for me I will pay what I must for the best products available). One is the pervasive claim/belief that synthetic oils will cause engine oil leaks to occur. I will not mock that assertion as being totally inaccurate, as there is plenty of anecdotal "evidence" that synthetic oils will cause leaks to appear where once there was no leaking. In my reading on that subject it comes down to this. Synthetic oils do not "cause" engine oil leakage. Rather, they create a situation that "allows" leaks to occur. So, what looks at first like an ambiguity at best, and weasel wording at worst, can be explained rather simply. Synthetic oils have superior cleansing additives that tend to get rid of the very materials that may otherwise (with petroleum based oil) be present in sufficient quantity to hide or obscure oil leaks that would otherwise be occurring, So, conditions that would otherwise allow for a leak are masked because petroleum based oils do not clean deeply enough to let the oil leak occur. The synthetic oil additives, doing their superior job, will clean up those issues not handled by petroleum based oils, and a leak may appear.

So, it is not the synthetic oil that causes the leaks, when they occur. It is more that the leak condition already existed, but the petroleum oils did not keep things so clean that the actual leak ever began. Is the synthetic oil responsible for the leak? No. But, did it allow the leak to occur once it cleaned away the residue missed by the petroleum oil, well, yeah - that it did. Therefore, the synthetic oil is blamed for the leak, as opposed to being cheered for doing such a good job getting things cleaned up. Sadly, reverting back to petroleum oil will likely not "fix" the leak as the residue that once kept the leak from becoming evident is already gone. I get how frustrating this can be for someone who has switched to synthetic oil, where the synthetic only made it clear there is a sealing issue simply by cleaning things up so well. Personally, I would not have been very happy if a leak, much less a rear main seal leak (for example), were to start after moving to a synthetic oil. In fact, I may even be angry enough to be tempted to other folks to not use synthetic oil as it causes leaks - other than the fact that I know why this happens at times (not in all cases), and I also recognize all the massive benefit synthetic oil brings to the table. I would, instead, roll up my sleeves and get on with correcting a condition I would not have seen otherwise.

The other issue is one that I cry out about every chance I get. And, I was very pleased to see was clearly addressed in this thread by Steed73, and mentioned by a few other folks as well. The older, flat tappet engines used in First Generation Mustangs and Shelbys, need Zinc, or actually Zinc and Phosphate, in their engine oil. Most modern engine oil no longer has Zinc in it. The reason is because it turns out Zinc fouls catalytic converters. So, in correcting a problem with Zinc for newer, catalytic converter based cars, the oil manufacturers have caused a potential problem for older engines - namely a lack of Zinc that will result in excessively and badly worn camshaft lobes, and lifter faces. The situation is one where anyone with old school flat tappet engines needs to make certain their engine oil has Zinc in it, or they need to use a Zinc additive. For older engine that are rebuilt and fit with a roller hydraulic valve train, as opposed to keeping the old school flat tappet valve train design, Zinc is not needed. But, it does not hurt for it to be present as our pre-74 vehicles were not equipped with catalytic converters.

Now, finally, we get to the place where I give my sworn testimony re: which oil is "best." Right out the gate I will confess this is both my opinion, and meant in the context of the vintage vehicles Lynda and I have, and how we drive them. And, I will provide my reason(a) for why I have chosen as I have. But first, we have gotten to the point with automotive engine oil where I can say there really is no "bad" oil. There may be incorrect weights and/or additive choices based on certain factors (flat tappet valve trains vs hydraulic roller valve trains, environmental temperature, intended use of the engine, etc.). So, here it is. For our 1969 Shelby and 1973 Mustangs I use AmsOil Z-Rod 10/30 oil (https://www.amsoil.com/p/z-rod-10w-30-synthetic-motor-oil-zrt/). It is the correct viscosity (10/30) per engine builder/vehicle manufacturer, has the Zinc needed for the old school flat tappet valve train design of their engines, and in some really well designed tests has been proven to be the very best of the best of engine oils (of the best). Some of the more recent, really good tests I have seen ware performed by Project Farm (YouTube Channel name). I find the guy who presents the tests on the Project Farm videos does a terrific job - matching the quality and extent of the tests run on a lot of different things (I tend to watch his videos on car parts, oils, and automotive tools - check his channel out, I am a raving fan). The Project Farm video re: oil comparisons that involve AmsOil Z-Rod are at the following links:

https://www.youtube.com/watch?v=TWuKvnCq1js

https://www.youtube.com/watch?v=E2zS8MyvJxU

https://www.youtube.com/watch?v=rPLrknPf3Do

Okay, I now rest my case... YMMV

Wow. Thanks for all the info. Great read.

 

[c9zx]

Wow! This question is the car guy equivalent of the question, "What religion or sect is the best?" I always find the opinions entertaining and sometimes humorous. It never fails to bring forward staunch support of oil X. Chuck

 

[Bobby]

Many opinions, everyone has them.

I use the Valvoline VR1 20w50, old design of engines were never designed to run on current thin oils.

Mind you I run full synthetic in everything else, big fan of them.

The thicker oil with the forementioned zinc is recommended, the old engines are very heavy, all pieces in there are also heavy, my belief if the 20w50 acts some of a "shock absorber" for the rod bearings as well.

I’m in total agreement. The older cars have larger tolerances so they need thicker oil. I ran 10w-40 back in the day and my current Mach 1 gets the same. It’s all subjective and up to each individual preferences.

 

[lectricegg]

I have another can of worms to open on oil. If you store your car over winter, do you change the oil in the fall before storage or in the spring when you get it ready to run? I always felt fall was better so the old oil, which I was told was acidic, didnt sit all winter long on the engine parts. Your thoughts?

 

[Sheriff41]

 

[Cleveland Crush]

View attachment 74353

That settles it, the best oil is from the Best Oil Company!

 

[Ron Tanzi]

Mad Irishman is so correct. Jaybale23 definitely opened up a can of worms with his inquiry. But, as luck would have it, there are no really bad answers, mostly because engine oils overall have become quite refined with their protective abilities as compared to oils from as recently as the 60s and 70s. And, opinions exist aplenty, to include my own thoughts. Of course, I feel my opinions have some credible backing as I have made a sincere effort to form an opinion based on original engine oil requirements from the vehicle manufacturer, and based on my own evaluations when reviewing research results from several credible sources. So, following I offer my thoughts on the matter.

The engine oil weight recommended by Ford for a particular year and engine size is what I tend to follow. For our 68 Shelby GT500 with its phenomenal 438CJ engine I use a 10/30 weight oil. The 351W (not C) engine in our 1973 Mach 1 came out of a 1994 F-150, and was built to a moderate street/street degree, resulting in a spirited 360HP at the crankshaft - enough to keep things thrilling, especially with its 3.5:1 TractionLok rear axle gear set and the transplanted 4 speed AOD tranny. The engine rebuilder apparently recommended 10/30 oil for it (just like the Shelby), so as with the GT500, I have been using 10/30 for the Mach 1 also. The same goes for our 1973 Mustang Convertible and its bone stock 302 2v engine, 10/30. But... In the event any of the engine were to begin to use or burn oil due to the engine getting worn I will move to a 20/40 weight oil right away. And once that 20/40 oil begins to get used/burned "too quickly," I will have my excuse, er, I mean, reason for rebuilding the engine with the alleged problem. And, of course, I will be rebuilding the affected engine in a way that it will have superior performance and longevity issues addressed from the inside out. For me (getting off track a little, sorry) that would include moving to a roller hydraulic valve train design, inserting bronze wall valve guides, using single piece, high quality intake and exhaust valves, aluminum alloy high performance pistons and high performance connecting rods, hardened valve seats, Perfect Circle "real" valve guide seals as opposed to the upside umbrella oil splash diverter excuse for a seal from the factory design, dual roller timing chain, and timing gears that are all metal (no nylon/plastic tips on the cam gear teeth). Okay, back to the main subject in this thread now...

The next hurdle to deal with is deciding between petroleum based and synthetic oils. For me, the decision was an easy one. Synthetic engine oils outperform petroleum based engine oils - hands down in all categories other than price per volume. I dare say there really is no competition between petroleum and synthetic oils. And, although the petroleum oils are less pr any given volume, the synthetic oils offer a greater value, period -no qualifying statements needed. That said, a high quality petroleum oil that incldues the various additives in its blend for any particular purpose is going to be a good choice, although the synthetic oils will still beat the petroleum oils in every performance category.

Alas, there are two things to consider when dealing with synthetic oil (I am purposely ignoring the cost of synthetic oils, as for me I will pay what I must for the best products available). One is the pervasive claim/belief that synthetic oils will cause engine oil leaks to occur. I will not mock that assertion as being totally inaccurate, as there is plenty of anecdotal "evidence" that synthetic oils will cause leaks to appear where once there was no leaking. In my reading on that subject it comes down to this. Synthetic oils do not "cause" engine oil leakage. Rather, they create a situation that "allows" leaks to occur. So, what looks at first like an ambiguity at best, and weasel wording at worst, can be explained rather simply. Synthetic oils have superior cleansing additives that tend to get rid of the very materials that may otherwise (with petroleum based oil) be present in sufficient quantity to hide or obscure oil leaks that would otherwise be occurring, So, conditions that would otherwise allow for a leak are masked because petroleum based oils do not clean deeply enough to let the oil leak occur. The synthetic oil additives, doing their superior job, will clean up those issues not handled by petroleum based oils, and a leak may appear.

So, it is not the synthetic oil that causes the leaks, when they occur. It is more that the leak condition already existed, but the petroleum oils did not keep things so clean that the actual leak ever began. Is the synthetic oil responsible for the leak? No. But, did it allow the leak to occur once it cleaned away the residue missed by the petroleum oil, well, yeah - that it did. Therefore, the synthetic oil is blamed for the leak, as opposed to being cheered for doing such a good job getting things cleaned up. Sadly, reverting back to petroleum oil will likely not "fix" the leak as the residue that once kept the leak from becoming evident is already gone. I get how frustrating this can be for someone who has switched to synthetic oil, where the synthetic only made it clear there is a sealing issue simply by cleaning things up so well. Personally, I would not have been very happy if a leak, much less a rear main seal leak (for example), were to start after moving to a synthetic oil. In fact, I may even be angry enough to be tempted to other folks to not use synthetic oil as it causes leaks - other than the fact that I know why this happens at times (not in all cases), and I also recognize all the massive benefit synthetic oil brings to the table. I would, instead, roll up my sleeves and get on with correcting a condition I would not have seen otherwise.

The other issue is one that I cry out about every chance I get. And, I was very pleased to see was clearly addressed in this thread by Steed73, and mentioned by a few other folks as well. The older, flat tappet engines used in First Generation Mustangs and Shelbys, need Zinc, or actually Zinc and Phosphate, in their engine oil. Most modern engine oil no longer has Zinc in it. The reason is because it turns out Zinc fouls catalytic converters. So, in correcting a problem with Zinc for newer, catalytic converter based cars, the oil manufacturers have caused a potential problem for older engines - namely a lack of Zinc that will result in excessively and badly worn camshaft lobes, and lifter faces. The situation is one where anyone with old school flat tappet engines needs to make certain their engine oil has Zinc in it, or they need to use a Zinc additive. For older engine that are rebuilt and fit with a roller hydraulic valve train, as opposed to keeping the old school flat tappet valve train design, Zinc is not needed. But, it does not hurt for it to be present as our pre-74 vehicles were not equipped with catalytic converters.

Now, finally, we get to the place where I give my sworn testimony re: which oil is "best." Right out the gate I will confess this is both my opinion, and meant in the context of the vintage vehicles Lynda and I have, and how we drive them. And, I will provide my reason(a) for why I have chosen as I have. But first, we have gotten to the point with automotive engine oil where I can say there really is no "bad" oil. There may be incorrect weights and/or additive choices based on certain factors (flat tappet valve trains vs hydraulic roller valve trains, environmental temperature, intended use of the engine, etc.). So, here it is. For our 1969 Shelby and 1973 Mustangs I use AmsOil Z-Rod 10/30 oil (https://www.amsoil.com/p/z-rod-10w-30-synthetic-motor-oil-zrt/). It is the correct viscosity (10/30) per engine builder/vehicle manufacturer, has the Zinc needed for the old school flat tappet valve train design of their engines, and in some really well designed tests has been proven to be the very best of the best of engine oils (of the best). Some of the more recent, really good tests I have seen ware performed by Project Farm (YouTube Channel name). I find the guy who presents the tests on the Project Farm videos does a terrific job - matching the quality and extent of the tests run on a lot of different things (I tend to watch his videos on car parts, oils, and automotive tools - check his channel out, I am a raving fan). The Project Farm video re: oil comparisons that involve AmsOil Z-Rod are at the following links:

https://www.youtube.com/watch?v=TWuKvnCq1js

https://www.youtube.com/watch?v=E2zS8MyvJxU

https://www.youtube.com/watch?v=rPLrknPf3Do

Okay, I now rest my case... YMMV

Great dissertation sir. I am a big fan of Project farm as well and I recommend everyone watch his videos. I think he does a great job and an important service to the consumer.