355 not quite what I was expecting

Discussion in 'Engine Topic' started by Lewis82871, Jan 6, 2016.

  1. Lewis82871

    Lewis82871 New Member

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    Need some input here,I built a 30 over 350 2 bolt main,running stock crank,rods,8:1 flat tops,edelbrock big valve heads-64cc 185 runners,comp 292 cam 501 lift int & exst,comp timing chain,comp roller rockers,edelbrock rpm intake,demon 625 carb,msd ignition,hedman headers with flowmasters 40 series dumped before the rear axle,4l60e with 2500 FTI stall/trans-go shift kit & 342 gears
    Question is would anyone take a wild guess as how much hp this combo would be ( ballpark ) it just seems to me that I'm not putting enough power to the rear wheels,tranny is new
    To me it should have more get up than it does,thinking about switching to 373's in hopes it would bring it alive,it's my daily driver @ 8.2 mpg
    Thanks for any help or advice ( positive please )
     
  2. CNC BLOCKS

    CNC BLOCKS Veteran Member

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    With that compression and that big of cam and if the block is not decked your dynamic compression is probably low.
     
  3. 73 Z

    73 Z Veteran Member Gold Member

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    How you get 8:1 with flat tops & 64cc ?
     
  4. camarolife78

    camarolife78 Veteran Member

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    That's my thought, unless they were the stock style flat tops that were not true flat tops. Either way 8 to 1 is way low
     
  5. night rider

    night rider Veteran Member

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    If your compression is 8:1, that is half of your prob, and the big cam is the other half.

    You need a bare min of 10:1 compression for that cam to work right
     
  6. F-Bodypilot

    F-Bodypilot Veteran Member

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    Something does not add up, flat tops with a 64cc head should put you around 10.0:1.
     
  7. CNC BLOCKS

    CNC BLOCKS Veteran Member

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    I bet you will find its just a stock lower end with dished pistons that are about .045 in the hole.
     
  8. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    Beside your compression vs cam issue, your torque converter is too tight for that cam, which has a basic operating range of 3,000 - 6,200 rpm.

    The steep first gear on your transmission should work well with your 3.42 gear, I don't see any gain in switching to a 3.73. I've ran both.

    Have you taken this car to the drag strip and recorded some times? That's a pretty telling story.
     
    Last edited: Jan 7, 2016
  9. Lewis82871

    Lewis82871 New Member

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    The pistons are flat tops with reliefs,I built the motor
    When the machine shop ordered them for me he said they were 8:1
    I understand the cc & runners affect the total compression ( correct ? ) if there's a formula for a total by all means let me know,this was my first motor build & basically went off the machine shops recommendations ( probably a mistake but it is what it is now ) I haven't been to the strip as everything around here is closed for the season,truck does run out great & sounds mean as hell but I know there is something or more than one I should've done different,just picking your brain what could be done to make it better Thanks for any help !!
     
  10. Lewis82871

    Lewis82871 New Member

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    It does have flat tops with dish relief
    Machine shop ordered them & are supposed to be 8:1
    I know the cc & runners effect total compression
    If they're formulas please let me know,this was my first true engine build & went off the machine shops advice ( prolly a mistake but trusted them as they've been doing engines for 35+ years )
    Thanks for the advice/help
     

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