1974 engine oil, no mods. Thoughts?

tvmaster

tvmaster

True Classic
Time for the first oil change. Been reading lots of threads, but what the hell, it’s 2021.

I’ve cut and copied some of your favorites. 1974 engine, with no major mods I know of.

synthetic or regular, and weight favorites for a moderate, marine climate (SoCal) where it’s mostly dry and air temperature rarely drops below 50f.

The Valvoline shows up here a lot, 20w50. Unsynthetic, Sound good?
 
These engines are pretty happy on 20w50. Unsynthetic? You mean standard petroleum? Yeah, that's fine. Valvoline would be fine. I ran Castrol 20w50 for years in my 1300 street car. Never had an issue. Hot climate and driven daily.
 
Steve Hoelscher said:
These engines are pretty happy on 20w50. Unsynthetic? You mean standard petroleum? Yeah, that's fine. Valvoline would be fine. I ran Castrol 20w50 for years in my 1300 street car. Never had an issue. Hot climate and driven daily.
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lol. Sometimes you write things while you’re in the garage, and then maybe not read read them back. No synthesizers.
 
Someone here said since we do not have roller tappets, we should use an oil with zinc. Mobil 1 Turbo Diesel truck. 5W40.
or Mobil Delvac 5W-40. If you read the fine print on the label you find zinc alkyl dithiophosphate. It was in stock at Pep Boys $32.99 / gallon. This PepBoys was having a 40% off sale because AutoZone was taking over. My price was $19.79 / gallon.
 
johnph said:
Someone here said since we do not have roller tappets, we should use an oil with zinc. Mobil 1 Turbo Diesel truck. 5W40.
or Mobil Delvac 5W-40. If you read the fine print on the label you find zinc alkyl dithiophosphate. It was in stock at Pep Boys $32.99 / gallon. This PepBoys was having a 40% off sale because AutoZone was taking over. My price was $19.79 / gallon.
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Good deal. Does EVERY, factory, exxe engine not have roller tappets?
 
johnph said:
No X 1/9 have roller tappets. I think that was a 90s or 00s tech advancement.
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Maybe Bernice mentioned diesel? This is my Haynes Manual, but is it outdated?

39E15D1B-2EBC-428F-8E2F-B03399A604CC.jpeg
 
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tvmaster said:
Time for the first oil change. Been reading lots of threads, but what the hell, it’s 2021.

I’ve cut and copied some of your favorites. 1974 engine, with no major mods I know of.

synthetic or regular, and weight favorites for a moderate, marine climate (SoCal) where it’s mostly dry and air temperature rarely drops below 50f.

The Valvoline shows up here a lot, 20w50. Unsynthetic, Sound good?
Click to expand...
I just went shopping at WalMart for oil to do this year's pre-season oil change. I was looking for my old stand-by, Castrol GTX 10w-40.

They had lots of synthetics, but only 10w-30 in dino oil and it was in the WalMart house brand. They had all sorts of other weights of oil but they were all synthetic blends or full synthetics. I bought Castrol GTX 10w-40 in a "high mileage" formulation that was a synthetic blend. I will look at the parts stores to see if I can find a full dino 10w-40, which I would rather use if I can find it.

My car does at the most 2,000 mi a year, and this year I expect to be doing more projects on it so I doubt if I'll put 1,000 on it, so I didn't lose any sleep over it.

My machinist buddy gets asked a lot what oil he recommends for rebuilt engines that leave his shop. For stock rebuilds, he usually tells them to use the same weight of oil that's in the owner's manual, and if at all possible, don't use a synthetic if the engine did not come from the factory with a synthetic. He tells them to change the oil and filter after the first startup and run in, after the first tankful of gas, and then after the first 1,000 miles. The insides of engines can't be cleaned like they used to, the environmentally friendly detergents of today are a joke compared to the hot caustic soda used in the past.
 
10 years ago, I had my 1979 X1/9 engine rebuilt at Midwest X1/9. Matt told me that the bottom end of the engine looked brand new. I had about 75K miles on at the time. He attributed it to the relativity low miles for it's age and the frequent oil changes I did. Since the X wasn't a daily driver back then ( and still isn't) I usually changed the oil in the late fall, when I put it away for the winter and again in the late spring or early summer when I got it back out again.

I had used Castrol 20w50 probably 90% of time and I still use it to this day. He certainly did not recommend using synthetics "because why change what is oblivious working well."
 
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My thoughts are that 80's and older engines weren't designed to run on synthetic so I have always stuck to Castrol 20-50w (except once). In one of my industrial college courses I tested the viscosity of different oils and was surprised at the outcome. My favorite oil that I had always run in all my cars was Valvoline 20-50 ( I'm in Cali) and it actually broke down much sooner than Castrol 20-50w did, so I switched and never looked back.

One exception - When I had my VW Vanagon motor built up from a 2.1 to a 2.4L the builder GoWesty (the end all for Vanagons) told me to switch to synthetic oil after the first two oil changes. Well I can't say that had anything to do with it but my rings never seated and the bottom end had to be rebuilt within 30k miles. Since then I only run dyno and I now have 210,000 miles since that rebuild and the engine burns a quart about every 1200 miles.

On break in (the second time) I learned that asides from varring ones speed one should always take a new motor up to say 65-75 mph then let off fully and compression down to 30-40 mph. When I picked up my VDub from GoWesty 200 miles away I must have done this 1-2 dozen times on the way home. Needless to say the rings seated with no problems. When and if I ever get my built HP 1300 motor in and running you can bet I will follow the same break in, and after the initial special break in oil run I will switch to Castrol 20-50w.
 
mwp8101 said:
10 years ago, I had my 1979 X1/9 engine rebuilt at Midwest X1/9. Matt told me that the bottom end of the engine looked brand new. I had about 75K miles on at the time. He attributed it to the relativity low miles for it's age and the frequent oil changes I did. Since the X wasn't a daily driver back then ( and still isn't) I usually changed the oil in the late fall, when I put it away for the winter and again in the late spring or early summer when I got it back out again.

I had used Castrol 20w50 probably 90% of time and I still use it to this day. He certainly did not recommend synthetics.
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Not particularly. I have run Redline and Mobil 1 Synthetics in my cars, including my racecar. They have been great.
 
I also think fully synthetic is ok. Oil has developed much during the years and modern oil should work also in older cars. According the manual, my Uno Turbo engine should have 15w40 fully synthetic and that engine doesn't differ much from a X1/9 engine. Why the X1/9 manual is stating mineral oil is probably because synthetic oil did not exist at the time the car was produced.
However I can't find synthetic 15w40 here (except diesel truck oil) so I use synthetic Valvoline 10w40 instead and it is working fine.
 
I run Valvoline Racing VR oil in all my old Fiats now. It is high zinc and has all the standard additives for road car oil in terms of detergents and so on. I don’t put many miles (well under 5K) on and change once a year.

I use Bosch or Mann filters. Other good alternatives are Wix and Napa (Wix makes Napa filters).

I had a bad experience with a K&N with a stuck bypass on one of my other cars and won’t use one again.

The whole synthetic thing is a non issue that stems from people believing their old cars when changed to synthetic leaked more oil years ago. I have not observed that on my OE 1969, 1970, 1985 or 1992 engines which all ran on Castrol for decades. My 850 continues to only leak from the drain plug, the Miata continues to leak from a variety of places (as did my Toyota). The X barely drips anything ever.

Many of the Diesel oils have had their zinc levels dropped because of their own catalyst issues (phosphorous in the zinc-dialkyl-dithiophosphate unfortunately creates a phosphate coating on the matrix reducing converter efficacy).
 
kmead said:
I run Valvoline Racing VR oil in all my old Fiats now. It is high zinc and has all the standard additives for road car oil in terms of detergents and so on.
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There are 3 types of Valvoline Racing VR available; 5w50 (synth.), 20w50 (mineral) and 10w60 (semi synth.). Which one do you use? I've learned that manufactures guidelines for viscosity is important to follow, at least the last two numbers. I haven't seen any synthetic racing oils with 15, 10 or 5w40 specs. so I am a little bit confused what to use. On the other hand my UT engine has been rebuilt (factory specs) and upgraded with a Volvo 850 T5 R Turbo. The car is heavily tuned to 240hp so I am not sure Fiat oil specs is still applicable.
Currently I am using Valvoline 10w40 but is it optimal?
I know this is a forever ongoing debate but would appreciate the opinion from people with experience in tuning and racing.
 
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Bjorn Nilson said:
There are 3 types of Valvoline Racing VR available; 5w50 (synth.), 20w50 (mineral) and 10w60 (semi synth.). Which one do you use? I've learned that manufactures guidelines for viscosity is important to follow, at least the last two numbers. I haven't seen any synthetic racing oils with 15, 10 or 5w40 specs. so I am a little bit confused what to use. On the other hand my UT engine has been rebuilt (factory specs) and upgraded with a Volvo 850 T5 R Turbo. The car is heavily tuned to 240hp so I am not sure Fiat oil specs is still applicable.
Currently I am using Valvoline 10w40 but is it optimal?
I know this is a forever ongoing debate but would appreciate the opinion from people with experience in tuning and racing.
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240hp in an exxe? F@#$.....
 
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