Engine oil

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what's everyone's opinion on engine oil for a 68 imperial with a 440. I am going to put in a 160 or 180 thermostat in it and it is due for an oil change just curious what the best oil for these. Should I go with 10-30, 10-40 or like a 15-40 diesel oil that has all the extra vitamins & minerals in it. The motor is original & has never been rebuilt. It runs pretty good but does blow a little bit of smoke when you start it after it has been sitting for a while
 
Flat tappet cams need zinc and phosphorus among other things, there are several oils that supply them, valvoline and mobile make "classic car" and "hot rod" and " older car" branded oils, as do the performance oil manufacturers, driven, joe gibbs, amsoil, schaeffer, lucas, etc. Stick with the recomended weight, and take your pick of the appropriate oil. Diesel oil can supply them as well, but you may want to check the relative amounts of additive if going with it.
 
In reading the owners manuals from Chrysler back then, even straight-weight 30 was common in areas where the temps dropped to 32*F, then the 10W-30 and 20W oils past that. Probably even 10W-40.

For general principles, 10W-40 viscosity. Other than that, a brand which has an API rating of "SL, which was the last rating that was supposed to have at least 1000ppm of zddp in it. Probably a semi-synthetic oil too.

With all of the online purchase possibilities of modern times, no need to just use what is available locally.

Might be better to look at what to NOT use? Anything currently OEM-spec, as Dexos-branded oils, for one. Although their zddp content of Dexos1 and "SP" rated oils is supposed to be at 900ppm. You can look in the Virgin Oil Forum postings of oil analysis at www.bobistheoilguy.com and also the PQIA website for verifications.

I used to be a proponent of Diesel-rated oils in the past, due to their higher zddp levels and better detergency levels. THEN came Lake Speed, Jr. and his comments about diesel-oriented zddp being a different style of zddp than was optimum for gas engines! At the same time, there are many other moving parts in a diesel engine that need zddp, too. I used Rotella T6 5W-40 (when that was the syn oil spec for modern diesels and not used on gas engines) in an engine with a 210@.050, .440 lift cam and stock valve springs for well past 100K miles with no indication of lobe wear issues.

Yet Mr. Speed, Jr. has stated that in dyno tests, the diesel oils did not like gas engines. I suspect their gas engines were probably race engines rather than reasonably-stock motors. It was not stated, so that possibility exists. You can watch his videos on YouTube as himself or under the moniker of "The Motor Oil Geek" to look at his information and see what you think of it. He was the designer of the Joe Gibbs Driven oil line when he worked for Gibbs Racing.

If you do your own oil changes, the available products can be endless, including online purchases. IF you let others do it, then head toward a full-syn oil at the best viscosity match for your particular temp ranges. To do that can escalate the price of a 5qt full-syn oil & oil filter change to the $100.00 range quickly! As a 5 qt jug of the same oil at WalMart is abt $30.00 USD.

YOUR judgment call,
CBODY67
 
Basically I was hoping to find VR1 in 10-40 but they only had it in 10-30 or 20-50. so I just bought napa premium 10-40 & Lucas Oil TB Zinc Plus additive
 
I run Penn Grade or more recently Driven because it was in stock.
 
Couple of thoughts....I would not use a 160 thermostat, this is below factory stock of 180. Later on I think they recommended 195 even for these cars that came with 180 stock. Also, use a hot rod/classic car oil like Amsoil rather than racing oil. Racing oil is meant to be changed frequently it does not have a lot of detergent or corrosion inhibitors.
 
Couple of thoughts....I would not use a 160 thermostat, this is below factory stock of 180. Later on I think they recommended 195 even for these cars that came with 180 stock. Also, use a hot rod/classic car oil like Amsoil rather than racing oil. Racing oil is meant to be changed frequently it does not have a lot of detergent or corrosion inhibitors.
the reason I was looking to go with a 160 is. I am Installing a Sniper 2 EFI system I have been watching and reading a bunch of videos & install stuff about throttle body efi systems. There were 4 common items/issues people have come across. Makes sure the electrical install is done properly, lowering to a thermostat in the 160-180 range, blocking off the heat crossover in the intake manifold, and if the intake manifold is a dual plane a 3/4" or taller spacer is needed or modifying the manifold so there is about 3/4 gap between the base of the EFI & the part that separates the two planes in the intake manifold
 
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Basically I was hoping to find VR1 in 10-40 but they only had it in 10-30 or 20-50. so I just bought napa premium 10-40 & Lucas Oil TB Zinc Plus additive

Good choice. Add in only 2 oz of the Lucas additive. That will suffice. One CAN put too much ZDDP in, which will cause corrosion.
 
what's everyone's opinion on engine oil for a 68 imperial with a 440. I am going to put in a 160 or 180 thermostat in it and it is due for an oil change just curious what the best oil for these. Should I go with 10-30, 10-40 or like a 15-40 diesel oil that has all the extra vitamins & minerals in it. The motor is original & has never been rebuilt. It runs pretty good but does blow a little bit of smoke when you start it after it has been sitting for a while
AMSOIL Zrod oil has the extra zinc and minerals for our older engines. PM for more info!
 
I used Shell Rotella a few years ago but they dropped the zinc levels was down when the DEF issue hit the roads. I think that was around 200 - 2010)
Now, I use Valvoline VR-1 but the viscosity selection on that stuff is limited. I use the 20W-50 but I believe they have a straight 50 as well.
I also have used ZDDP additive as well. My slant six '72 Dart has been serviced with that for 20 years or so.
 
Regarding ZDDP...found this interesting article. From there:
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I think the forum compressed the image so the text looks fuzzy...
 
10w30 conventional oil in my 300J. Add ZDDP every change. Sure, Diesel oils have zink BUT, totally different additive package due to the soot in the oil. Stick with a good quality oil for gasoline engines and add the zinc. Or, use a specific oil for older flat tappet engines.
 
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