SR code SF code 455's whats the Difference

Discussion in 'Street/strip 400/430/455' started by calvin dubose, May 30, 2006.

  1. DeuceCoupe

    DeuceCoupe Member

    So I just found this thread on 455 cams.
    In fact, I am trying to calculate what torq/power these old motors might have actually made, so trying to figure the .050 lobe durations as commonly used today.

    I have some scrappy .050 info on 2 cams, and a guess on a 3rd one.
    .050intake - .050 exhaust - LobeSep - Int.Lift - Exh.Lift

    194-226-117 .388 .458 Clevite 1646 - guessing this is the 70-up "base" cam?
    206-220-117 .421 .450 (.050 guessed) guess for the "GS" cam ie the 70-455/370, 71-45/330, also 67-69 430/360?
    210-226-117 .455 .480 guess at the Stage 1 cam 70-455/360 72-73-455/270net etc

    These are REALLY guesses, just trying to put the picture together.
    Nov.1970 Road&Trac article does say that the "GS" engine 71-455/330 had a "slightly hotter" cam than the base 71-455/315 but that is just a mag article so could be urban legend?
    Any help appreciated thanks!!


    EDIT- well I just read the JPG from Dennis Manner so may have to re-think this. Maybe the .421 .450 lift cam was just for the earlier 430/360 years and there was no "hotter GS cam"?
    Looks like from 70-74 Buick did a lot more with LSA and cam advance but the two basic grinds (Base and Stage1) were the same or close anyway?
     
  2. BadBrad

    BadBrad Got 4-speed?

    The SF block (from a '70 Riv) in my car was drilled and tapped for the z-bar stud. :Do No:
     
  3. Jim Jones

    Jim Jones Wretched Excess

    Duane, first accept my apology for dredging up such an old thread. Secondly, there is reference to an "SG" coded 455 among this information, something I had never seen. Well, live long enough and anything is likely to happen. Today I saw a photo of an SG coded 455. This is from a car assembled at the Wilmington, Delaware plant, and the stamp appears to be original. After talking with the owner, and mentioning to him that I have a '70 SF coded 455 block from Wilmington car which has the VIN stamped on the passenger side deck surface, he stated his is also stamped on the passenger side.

    Any information you can share about the oddball "SG" code?

    SG_455.jpg

    -JPJones
     
  4. Electra Sweden

    Electra Sweden Well-Known Member

    The letters are in a disarray compared to other stamps of this kind I have seen on my engine and other online. So maybe a hungover summer intern confused F with G in a hurry? :)
     
  5. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    For all intents and purposes, there isn't a difference between 455 blocks despite what the specs say. Stated compression ratios, and HP ratings weren't very accurate. The Stage1 heads had bigger valves that supposedly took up more room in the combustion chamber resulting in a .5 difference in static compression. Probably wasn't that much though. The blocks themselves were pretty much the same. There were some differences in camshafts.

    Stage1Cams2.jpg

    CompressionCalculations.jpg
     
  6. Electra Sweden

    Electra Sweden Well-Known Member

    That paper looks it could be be solid gold! Where was it originally published?
     
  7. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    In a publication by the GS club of America.
     

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