What should I be using in a '83 SBC?

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Originally Posted by bullwinkle
Originally Posted by michaelluscher
Originally Posted by bullwinkle
Rotella T5 10W30 seems to do pretty well in these. It's possible to flatten cams in those, I had an '85 Chevy G20 van that ate one on a 305.
Diesel rated oil in a gas engine? I didn't know you could do that shrug Should I still add a zinc additive, or it's good out of the bottle? I saw they've got a "Multi Vehicle" T6 that's both CK4 and SN rated, but that's kinda thin 5W-30 They've got T6 5W-40 in good value 2.5 gallon bottles for a fair price, would that do it?
T6 would be good too-check Brickseek for local Wal-Marts carrying it for $15/2.5 gallon jug, that would work too. People add ZDDP to it too, but I'm not sure a 305 would have an aggressive enough cam to need it. T5 (&T6) were dual gas/diesel rated until recent (SN rating) times.
And if he can find some, also pick up a Fram XG5 while he's a Walmart, for around $25 he'll have enough oil for two oil changes and that XG5 should last for both OCIs,
 
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Originally Posted by chainblu
Those cams are super mild. No need for more zinc than what regular 10w30 has in it. There are thousands and thousands of flat tappet camshafts running right now, as you read this, without any kind of special oil and they haven't turned into broom sticks.
My flat tappet f150 has been living quite well with SM and SN 5w/10w-30 oil for the last 15 years.
 

SR5

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Originally Posted by BrocLuno
As long as that 305 is stock, any HDEO will be fine, but so would any good name brand marine oil like Quicksilver from Mercury. Bazzillions of boats out there with flat tappet cams..
Originally Posted by Red91
I'll be bold and recommend an sn rated pcmo straight 30.
Hey BrocLuno, Hey Red91, Good to see you both again ! SR5
 
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[Linked Image] [Linked Image] Walmart's been clearancing Delo 400XSP 5w40 and in some really slow stores I've still seen 400LE on the shelf from before they reformulated to meet API SN and CK-4 and reduced the Zinc and Phosphorous to 0.08%, for $5 a gallon that'd probably be a good oil for this engine if you can find any, one store I was in had 7 jugs of the old 400LE still on the shelf.
 
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That tiny LG4 Cam already broken in with ink pen strength valve springs will survive on anything in my opinion. A buddy is still running the 1984 LG4 out of my Z28 in his 1963 Chevy II from when I put in the 415". It's never had anything but regular old 10W-30 and still runs as good as ever.
 
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Originally Posted by blufeb95
[Linked Image] [Linked Image] Walmart's been clearancing Delo 400XSP 5w40 and in some really slow stores I've still seen 400LE on the shelf from before they reformulated to meet API SN and CK-4 and reduced the Zinc and Phosphorous to 0.08%, for $5 a gallon that'd probably be a good oil for this engine if you can find any, one store I was in had 7 jugs of the old 400LE still on the shelf.
400LE would be my choice in a old FTC, otherwise 10w/30 with 5 oz zinc additive.
 

SR5

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Originally Posted by Red91
Howdy. You've got to back me up on the straight weight suggestion.
To me a straight weight / monograde is the top hat and tails of the oil world, an old school but classy look. Long as the temperature is above freezing for startup. No shear with a monograde and now that they should all be Group II based, they are much improved over the old Group I stuff.
 
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Originally Posted by SR5
Originally Posted by Red91
Howdy. You've got to back me up on the straight weight suggestion.
To me a straight weight / monograde is the top hat and tails of the oil world, an old school but classy look. Long as the temperature is above freezing for startup. No shear with a monograde and now that they should all be Group II based, they are much improved over the old Group I stuff.
If today's monogrades are all group II based would that mean that their cold flow properties would probably be a lot better than what the old manuals that said not to use monograde 30 below 32F, because those manuals were written with the expectation that mono grade 30 oils would generally be oils formulated using cheap solvent refined base stock, Do you think an oil labeled as SAE30 consisting of almost all group II basestock would maybe perform like a 15W30 or 20w30 multigrade but isn't labeled as such because, one, almost nobody would buy 15W30, and two , you don't have to do nearly as many tests to be able to sell an oil as monograde, and thus really a modern monograde 30 could actually be used in the temperature ranges that a 15wX or 20wX are spec'd for on the viscosity/temperature chart?
 
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SR5

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Originally Posted by blufeb95
Originally Posted by SR5
Originally Posted by Red91
Howdy. You've got to back me up on the straight weight suggestion.
To me a straight weight / monograde is the top hat and tails of the oil world, an old school but classy look. Long as the temperature is above freezing for startup. No shear with a monograde and now that they should all be Group II based, they are much improved over the old Group I stuff.
If today's monogrades are all group II based would that mean that their cold flow properties would probably be a lot better than what the old manuals that said not to use monograde 30 below 32F, because those manuals were written with the expectation that mono grade 30 oils would generally be oils formulated using cheap solvent refined base stock, Do you think an oil labeled as SAE30 consisting of almost all group II basestock would maybe perform like a 15W30 or 20w30 multigrade but isn't labeled as such because, one, almost nobody would buy 15W30, and two , you don't have to do nearly as many tests to be able to sell an oil as monograde, and thus really a modern monograde 30 could actually be used in the temperature ranges that a 15wX or 20wX are spec'd for on the viscosity/temperature chart?
Yes I believe a modern SAE30 made on Group II would probably pass as something like a 15W30 multi-grade. You can get some very good ones with modern API SN-Plus add packages such as this Mag-1 SAE30 (Mag1 SAE30 PDF) Compare it to the Mag1 10W30 and it is the same add pack. The modern Mag-1 SAE30 linked to above has a Pour Point of -33C (-27F) and a Noack Volatility of only 5%. With a modern LSPI friendly Ca & Mg detergent package, a TBN of 7, a HTHS of 3.37 Cp, 200 ppm Boron, 79 ppm Moly and 850 ppm zinc. That high HTHS and low Noack is very impressive, and yes given a -33C pour point it should easily start below freezing now days, just not exactly sure how low.
 
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Going off of various pour point data, most sn rated 30 wt oil seems to behave like a 20w-30. We've speculated that possibly this is achieved with a touch of pao basestock. Idk if anyone ever confirmed that, but perhaps a company like shell slips a little gtl into their pcmo monogrades to provide a vi free blend with an improved cold flow capability. Again, this is strictly speculation, but I dont think its farfetched.
 
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Also OP, I did not intend to hijack your thread. I do think an sae 30 would be a fine option for any stock or slightly modified sbc. If I'm not mistaken your location is New York? Probably would be testing a mono to its limit in winter, but down where I'm from straight 30 is doable year round. A stout 10/30 like rotella t5 or m1 hm 10/30 would also be a good, thick multi grade 30. Of course, ilsac 10/30 does fine too. Overall my opinion is a decent 30 or 40, mono or multi. Even 20w-50 wouldn't be a bad choice in the summer months.
 
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Euro blend mobile 1 0w40 is what I would use in your car without any type of additive. My 94 ford E150 5.8l 351 engine I'm not positive it's a roller or flat tappet being they did go to the roller setup in 94 but I have read that the vans kept the flat tappet till 95. The majority say all 94 ford 5.8 did get the new roller setup. I still like to use a oil I know would work great either way.
 
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My dad had a 1978 Malibu with a 305. I still have the OM for it, and it has that exact same viscosity chart in it. The 305 is an absolute garbage engine that will fail eventually, if you want to keep it going for now extra zinc will be needed, so the HDEO plan is a good one. Very nice GP, when the engine gives up a mild 400 would work well in its place wink
 
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My dad had a 1978 Malibu with a 305. I still have the OM for it, and it has that exact same viscosity chart in it. The 305 is an absolute garbage engine that will fail eventually, if you want to keep it going for now extra zinc will be needed, so the HDEO plan is a good one. Very nice GP, when the engine gives up a mild 400 would work well in its place wink

My 83 305 has 240k miles. My last one (an 89 roller cam 305 had 332k miles). I've had several and known lots of people that had them, never heard anyone say anything like that. Gutless yes, unreliable...no. Remember it's basically just a 350 Chevy with a smaller bore. Same rods and crank.

They did have camshaft issues mainly 77-83. A friend of mine has the original cam in his 77 with 330k miles though. His dad bought new.

I run 0w40 euro in mine usually because it's my winter beater, cold starts at minus 20 or colder.

If it's low mileage I'd worry more about the cam. High mileage like mine it's either had the cam replaced years ago or it's not going to fail.
 

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My 83 305 has 240k miles. My last one (an 89 roller cam 305 had 332k miles). I've had several and known lots of people that had them, never heard anyone say anything like that. Gutless yes, unreliable...no. Remember it's basically just a 350 Chevy with a smaller bore. Same rods and crank.

They did have camshaft issues mainly 77-83. A friend of mine has the original cam in his 77 with 330k miles though. His dad bought new.

I run 0w40 euro in mine usually because it's my winter beater, cold starts at minus 20 or colder.

If it's low mileage I'd worry more about the cam. High mileage like mine it's either had the cam replaced years ago or it's not going to fail.

Yeah, I've never regarded, nor heard the 305 noted as an unreliable engine. Low on power? yep. Very poor choice to hotrod because of the small bores? Yep. But unreliable? No. There was a very high mileage Vortec 305 in a 1/2-ton at a local trailer park I did the IT for more than a decade ago, as I was friends with the manager. At the time it was one of the highest mileage vehicles I'd ever had the privilege of sitting in. IIRC, it had over 500,000km on it just going from memory. Didn't fog blue, wasn't maintained in any special way and, for a 305, still worked well; I'd say better than the 4.8L in my buddy's work-issued Sierra :LOL:
 
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