Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: Engine oil

  1. #1
    Join Date
    Dec 2019
    Location
    amersham
    Posts
    274

    Engine oil

    My engine manufacturer has recommended SAE 10W/30 oil for my Chevy 350. Looking at various websites the oil is listed in some cases as motorcycle oil is this usable in my engine ?. I presume that semi synthetic and fully synthetic
    is not recommended, which suggests it has to be mineral based for my engine.
    What about SAE 10W/40 ?
    Any recommendations welcome.

  2. #2
    Join Date
    Mar 2008
    Location
    Coventry
    Posts
    2,396
    A lot of us use including myself use valvoline vr1 racing oil 20w 50

    Paul
    AK, on the road Oct 2012

  3. #3
    Join Date
    Dec 2019
    Location
    amersham
    Posts
    274
    Thanks Paul
    I will have a look to see whats available.

  4. #4
    Join Date
    May 2004
    Location
    Perth
    Posts
    4,685
    Cheers, Clive

    (If I'm not here, I'm either in my new workshop or on the golf course!)

  5. #5
    Join Date
    Feb 2007
    Location
    Essex, UK
    Posts
    4,146
    Whichever oil you use, always stick a slug (or even a whole bottle) of break in oil additive in. Flat tappet cams need the extra zinc. Better safe than sorry
    Simon

  6. #6
    Join Date
    May 2016
    Location
    Hockley ,Essex
    Age
    58
    Posts
    511
    Quote Originally Posted by simon View Post
    Whichever oil you use, always stick a slug (or even a whole bottle) of break in oil additive in. Flat tappet cams need the extra zinc. Better safe than sorry
    Simon
    I have used the20/50 valvoline vr1 most of the time,
    although earlier on I did use a castrol 15/50 which is recommended for rv8's with lower mileage.
    The question that that I have with you about the break in additive is would it be a good idea to use in the rv8
    with a piper 270/2 cam and Rhoads hydraulic lifters ?
    thanks in advance,
    Chris.

  7. #7
    Join Date
    Sep 2010
    Location
    Nova Scotia
    Posts
    993
    My opinion, which follows the old saying: "free advice is worth what you pay for it", is the oil viscosity you need is dependant on bearing clearances. If the rod and main clearances are stock, then use what the engine OEM recommends. If your engine has been modified for increased performance, the clearances are often larger and a higher viscosity oil is required.

    I use Mobile 1 15W50 in mine as my clearances are higher. In fact, they are 0.0025" where Ford specs are from 0.0005" to 0.0015" but up to 0.0025" for their Police Interceptor engines and up to 0.0027 for the 427. This version of Mobile 1 also contains plenty of zinc.

    One thing I've noticed, is that no matter what viscosity oil you choose, they all have their viscosity converge as the temperature goes up. Basically at temp, the difference between them is much smaller than one would think. So even if you choose an oil that isn't 100% optimized for your engine, I doubt there's much too worry about.

    There's lots of charts on the net, but here's one that effectively shows the viscosity convergence:



    This why increasing your oil viscosity to increase oil pressure doesn't make much difference once the engine is hot. Yet there is some benefit; I think the oil molecules, or chains, are larger in the higher viscosity oils which help to fill in bearings clearances better. I'm now getting way past what I know. But back to viscosity only...

    The above graph does highlight the viscosity vs. temperature action well, but the graphs are based on only two points. In fact, the graph below shows the comparison based on many points:



    So, once you decide on a specific viscosity, the next step is to look for what brand is best. Additives like zinc is good, but as all oil should meet the latest API standards, they should all be safe.

    It appears that zinc is most beneficial during break-in and isn't really required after that, but this is quoting internet info which wasn't backed up.

    Another fact, which I can't remember where I go it, but maybe from an engine book, is to avoid 10W40. Apparently multi-grade oils have a base made to the first number (10 in this case), and that the qualities of the second number (40 in this case) is made up from additives. Over time, the additives break down and you're left with the first number viscosity. 10W40 uses a lot of additives, and going from 40 back to 10 is a big drop with very thin oil left. I will admit, I need to find this info and make sure I remembered this correctly, but the gist of it is correct.

    Of course there's always the next question.... which is the best oil filter to use... I think a very thick book could be written on that!
    John

    “A prudent person profits from personal experience, a wise one from the experience of others.”

  8. #8
    Join Date
    Sep 2009
    Location
    Leeds
    Posts
    3,056
    After having my 383 rebuilt a couple of years ago, it went from using 20W50 to my engine builders stated preference of 10w40 mineral oil - this is like trying to find rocking horse droppings and the only one i've found yet is Lucas oil. Millers where supposed to be starting to make it to, but i've not yet seen it for sale or advertised.

    What are the specs on your 350 engine Methoni ?? if standard i'd say that 20W50 mineral would be fine still.

    rgds
    Gary
    Conny - A Carnival Red Metallic (paint code Ref: Jag CGG/1811) Southern Roadcraft V8 ( SRV8 ) with 383ci stroker chevy.

  9. #9
    Join Date
    Mar 2007
    Location
    Maldon Essex
    Posts
    549
    This is the oil that my engine builder (John Sleath) recommends, as Simon says, for a flat tappet engine you need more zinc, so depending on your engine spec this may be the best option. Its the same as nealgs is looking at .

    http://www.lucasoil.co.uk/products/h...w-40-motor-oil

  10. #10
    Join Date
    Oct 2018
    Location
    Shipston-On-Stour
    Posts
    766
    I use Morris’s HD3 20/50 in my FE. Always have. Raced it with that and have 100% confidence in it. They also do a 10/40 (Servol). They are a great business. I guess many will not of heard of them but they are a top company . As far as I am concerned the big brands are exactly that, brands! https://morrislubricants.co.uk/produ...ngine-oil.html

Page 1 of 2 12 LastLast

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •