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350 small block horspower output

Discussion in 'The Hokey Ass Message Board' started by 1950kale, Jul 21, 2013.

  1. travj31
    Joined: May 19, 2008
    Posts: 1,520

    travj31
    Member
    from Western PA

    Back in the mid-90's, my dad had a mildly built 307 that he got for a song in a more door 55 sedan. First time at the track he was knocking off brand new 5.0 Mustang GT's and to say the least, they weren't happy! I was always shocked how good that damn thing ran for a "lowly" 307 in a rather big, un-aerodynamic car like the 55. By no means was it setting the world on fire, but ran really well for what it was.

     
  2. Truckedup
    Joined: Jul 25, 2006
    Posts: 4,660

    Truckedup
    Member

    Common thinking is certain engines are better than others based on old stories.Certain engines are so called "torque monsters", but the reality is they might make less torque than other engines more know for higher rpm's.
    It's pretty easy to build a 350 with 9.5 compression,aftermarket heads,single 4 barrel,streetable cam and headers that'll make 350-375 HP and a good amount of torque.This might be 2 grand depending on the builder's source of parts.
     
  3. 1950kale
    Joined: Jan 22, 2013
    Posts: 252

    1950kale

    awsome, sorry i wasent on, diddent have internet fro a coupple of days. but i'm actually trying to get this chunk of metal drivable by aug... & i have done this al ready & the engine runs beautifully on the frame. are you guys saying that if i put some Vortec heads on it it will get me better fuel econonmy & a little better power? thanks
     
  4. hoop98
    Joined: Jan 23, 2013
    Posts: 1,362

    hoop98
    Member
    from Texas

    I found the flow numbers on your swirl port heads and redid the stock simulation with a Q-Jet

    [​IMG]

    With Stock L31 Iron Vortecs and Comp XE 250H cam, I tried the Voodoo 250/256 in the simulation but the comp was best by about 10 Foot Pounds

    [​IMG]

    I played around and a 4 degree retard worked best. Intake at 110.

    [​IMG]

    So that's l31 heads, XE250H cam, and you will need a Vortec 4bbl intake.

    Oh the numbers are usually optimistic but for comparison you can see the improvement.
     
  5. 1950kale
    Joined: Jan 22, 2013
    Posts: 252

    1950kale

    oh wow this is very help-full, thank you very much now at least i know what to keep my eyes open for
     
  6. hoop98
    Joined: Jan 23, 2013
    Posts: 1,362

    hoop98
    Member
    from Texas

    100 HP for about 750 not bad!
     
  7. Hey hoop, I know you've said before in another thread which computer dyno you used for those but I can't remember or find it.

    I'd like to run a sim on a 350 vortec roller block & heads fitted with 3.25 stroke & 327 flat tops w/ valve reliefs pistons.
    Not sure of the cam yet but heads have guides cut and will have springs to match, probably a big cam to get dynamic compression in range.
    0.040 quench and 10.5 ish static compression.
    Should be better on gas, and rev faster and higher.
    (?might need aluminum heads on this one ? But I have the iron heads on the shelf)

    Then there's my favorite 307 combo.
    Flat top pistons w/valve reliefs (stock bore), 305 (416) heads w/ springs to match the cam, 0.017 steel head gasket , 0.04ish quench, and a comp XE 262 cam hydraulic flat tappet. oem 305 ho aluminum intake. 625 4 bbl on a 1" spacer. 1-1/2" long tube headers.
    ($600.00 in this combo btw.)
     

  8. Kale,
    You are going to detune it and expect better mileage, that's actually backwards but it is a different discussion.

    You have dropped the 'puter and EFI and added basic stock old junk, take your original HP numbers and drop them by 15-30%. That will ballpark you.
     
  9. hoop98
    Joined: Jan 23, 2013
    Posts: 1,362

    hoop98
    Member
    from Texas

    Desktop dyno

    31Vick, I'll take a stab at yours today.


    Posted using the Full Custom H.A.M.B. App!
     
    Last edited: Jul 25, 2013
  10. hoop98
    Joined: Jan 23, 2013
    Posts: 1,362

    hoop98
    Member
    from Texas

    31Vicky

    Here is your 327

    First with Comp 270HR (8.49 DCR)

    [​IMG]

    Next with 280 HR (8.17 DCR)

    [​IMG]

    And with 286 HR (7.97 DCR)

    [​IMG]
     
  11. Looks like that 327 will run pretty damn good hoop, thanks
     
  12. hoop98
    Joined: Jan 23, 2013
    Posts: 1,362

    hoop98
    Member
    from Texas

    307 first with the cam in at 106ICL, second retarded to 110 ICL

    I used the flow numbers I found for your 305 heads and guessed at 9.5 compression.

    106 Intake Centerline
    [​IMG]

    110 Intake Centerline

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]
     
  13. The 307 / 305 head (casting 416) combo with 0.017 head gasket actually measures out to 10.43:1 average across 8 cylinders. That's with stock uncut block, and stock un cut heads and all the other mass production variances. I busted over all the hard edges in the combustion chambers to eliminate potential hot spots, and I'm more than reasonably certain that all chambers aren't exactly identical.

    That's one sweet little combo for $600.00 ain't it?
    Not going to break any records with it but the hp:dollar ratio is phenomenal and 330 ish in a hot rod is plenty fun.
     
  14. hoop98
    Joined: Jan 23, 2013
    Posts: 1,362

    hoop98
    Member
    from Texas

    With 10.43 :)

    [​IMG]

    Voodoo 262/268 @110 ICL

    [​IMG]
     
  15. 1950kale
    Joined: Jan 22, 2013
    Posts: 252

    1950kale

    kind of an old thread but what HP & torque numbers do you think i would see on the 1991 350 with stock heads and cam, but 4 bbl edelbrock aluminum intake (high flow) with a holley 600 and block hugger headers? would that be better than the Quadrajet? (someone gave me a holley 600 off a 237 for free so i rebuilt it. i drove the truck down the highway the other night to get windows, it still docent have a bed but ill say, you drop it to third and hit the gas and that thing is gone! more power than anything I'm used to
     
  16. ChanceDean
    Joined: Feb 7, 2014
    Posts: 152

    ChanceDean
    Member

    A cheep route to help that engine run a little better is just putting vortec heads on it from the '95 and up sbc's. with this you have to change to a vortec intake but it does help with milage.


    Posted using the Full Custom H.A.M.B. App!
     

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