GS350 vs. skylark 350 what are the differences?

Discussion in 'Small Block Tech' started by 70skylark350, Aug 6, 2018.

  1. 70skylark350

    70skylark350 Jesus loves you unconditionally

    so I know this topic has been posted before but I could not find it on a thread search. What is the difference between the 70 GS350 and the Skylark 350?

    Compression ratio? Cam? and what about the car, were there suspension and rear end differences?
     
  2. rkammer

    rkammer Gold Level Contributor

    In 1970 there were three 350 cu. in. engines available. A 260 HP 2 barrel carb (9.0 compression) , a 285 HP 4 barrel carb (9.0 compression) , and a 315 HP 4 barrel carb (10.25 compression). All three engines were available with any Skylark but the 315 HP engine was standard on the GS350.
     
    1967 Big Buick likes this.
  3. rkammer

    rkammer Gold Level Contributor

    Rear Axles:
    3 speed manual - 2.93
    350 2 barrel - 2.56 standard, 3.23 optional
    350 4 barrel - 2.73 standard, Optional - 2.56 economy, 3.23 performance
    GS350 - 3.23 standard, Optional - 3.42 performance

    Posi was available with all axles but not standard on any of them (even on the GS350) unless a performance axle was ordered. Then, posi was standard.
     
    Last edited: Aug 6, 2018
    1967 Big Buick likes this.
  4. gstewart

    gstewart Well-Known Member

    Was the same cam used in all three engines?
     
  5. rkammer

    rkammer Gold Level Contributor

    As has been said in previous posts a few years ago, "it's complicated". Some say that all the 350 cams were the same up to 1970 and then, changed due to emission regulations after that. There is some info that says that the 315 HP GS350 in 1970 had a different cam. Here's a link that gives a lot of info on 350 cams over the years. It's a good read.

    http://www.v8buick.com/index.php?th...pecs-on-the-stock-buick-350-1973-2bbl.292468/
     
    MrSony likes this.
  6. Paul Stewart

    Paul Stewart Well-Known Member

    Here's the spec sheet on the 315 HP.....
     

    Attached Files:

  7. alec296

    alec296 i need another buick

    Engine power and compression are overrated.
    Figure 9.45 compression on the hi compression 350-4 with steel shim head gaskets. 9.2 with replacement fel pro gasket.
    The 9.0 compression engines are about 8.2 compression. As far as I know they don’t use the steel shim head gasket.
    Hi compression engine hp is closer to 260
    The “9.0” 350-4 is about 185 hp
    The “9.0” 350-2 is about 170hp basically the same as the 72 model.
    I thought 3.08 was standard in the gs350 rear axle. Or atleast that’s what I was told.
     
  8. rkammer

    rkammer Gold Level Contributor

    GS350 was 3.08 in '71 & '72. It was 3.23 in 1970
     
  9. Mark Demko

    Mark Demko Well-Known Member

    Correct:cool:
     
    rkammer likes this.

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