400 small block

Discussion in 'General Chevy & GMC Pickups Talk' started by Glen, Nov 28, 2002.

  1. Glen

    Glen Member

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    Ok guys, give me some input here. I have a chance to get a 400 small block for the best price (come and get it). It has the heads on it, a manifold, crank, pistons etc., but is missing the pan. I realize a tear down and rebuild is in order. How available are aftermarket parts, such as headers, A/C and Alt. brackets, etc. I am I really going to get that much more performance and horsepower than a regular old 350? What about fuel economy? This is going in my wife's '59 fleetside and will be backed by the original 4-spd. Are parts going to be so much more expensive that I should just by a used 350 for a few hundered dollars? I am used to dealing with 235, 261, 230 and 250 six cylinders. This v-8 stuff is new territory for me. Thanks.
    Glen.

    I've also got a '63 3/4 ton we bought new and a '60 c-60 with a 5 yard dump bed.
     
  2. 57heaven

    57heaven Member

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    :) howziit Glen!

    JMO, i would jump at the chance of running the sbc400.

    what is the final gear ratio of your truck?

    with the generous amount of low-end torque, the 400 does not need to run at rpms over 4500 rpm.

    just rebuild it stock, with QJet carb and intake, HEI and dual exhaust. that may be all you need!

    with the exception of rods, pistons, balancer and flywheel, sbc stuff will interchange.

    parts and gas mileage-wise, prices are about the same as sbc350.
     
  3. Glen

    Glen Member

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    myron,
    Thanks for the input. I was hoping it would work good. The '59 still has the stock rear end, which should be about 3.90. I may splurg and by CD's 3.38 gear set or check with some of the local shops here. I'm going to try to pick up the engine tomorrow and start tearing in to it.
    Glen
     
  4. 57heaven

    57heaven Member

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    [updated:LAST EDITED ON Nov-29-02 AT 04:05 PM (CST)]:) howziit again Glen!

    log on to www.smokemup.com

    using the diameter of your present-size tires and your 3.9 gear ratio, you can calculate engine rpm at any given speed.

    then, by recalculating with taller-diameter tires, you will see a reduction in effective gear ratio, and a corresponding decrease in engine speed, at any given speed.

    by choosing a taller tire, you may be able to relieve freeway engine strain, without resorting to overdrive trans, or a change in rear gears.

    BTW, i have 3.9 rear gears, with 29" tires, as compared to the commonly used 235/60-15, which has a 26" diameter. effective gear ratio is reduced to 3.50:1, so at 60mph, i'm cruising at 2,711rpm, not 3024rpm, by a simple change in tire diameter size.

    JMO, i would compare the labor charges of rebuilding your existing heads and connecting rods, versus buying new vortec heads(or world products heads), and aftermarket rods. if the cost difference is small, i would advise to buy new parts.

    www.dirttrackthunder.com has GREAT prices; their TRW hypereutectic pistons go for $169, yielding 8.8:1 compression ratio with your 76cc heads.

    new rods with good bolts sell for $119, a price that no machinist can rebuild for.
     
  5. chevy_man_3

    chevy_man_3 Member

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    Also remember that you have to get a flywheel for the 400 or you will tear the engine apart. The 400 is an externally balanced engine, it is balanced by the flywheel or the flexplate and the harmonic balancer. VO
     
  6. Glen

    Glen Member

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    Here is an update guys. Sorry to say I probably won't be using the 400. Someone has robbed one of the main bearing caps off of it while it has been sitting. I can buy a new one but then it will have to be line bored, adding a couple of hundred dollars to the rebuild cost. Several of the rod bearing caps have been taken off and some idiot horsed the crankshaft around a few times, bending several rods, scoring the journals with the bolts (regrind crank, all new rods), etc..... Well I guess I'm back to the 305 I was going to install. I will pick up a rebuilt long block this week ($589 exch.). Anyone out there want to buy a 400 small block, 4 bolt main, with a 2 barrel intake on it. I'm in Tulsa, OK. Make me an offer.
    Glen
    (glenlynn@aol.com)
     
  7. 57heaven

    57heaven Member

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    what a shame, what a waste.:'(

    JMO, don't throw it away. maybe the bearing cap will show up, and the block won't need align-bore.

    FWIW, a new crank, rods and pistonscan be bought at a cheap price.
     
  8. basketcase

    basketcase Member

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    With some careful shopping you could put that 400 together for the price of that 305 shortblock assy. The difference in the torque between the two would make a big difference in getting that heavy '59 rolling. Don't be affraid to save some money by using cast pistons on a basically stock rebuild. Chevrolet and everyone else have installed trillions of them over the years in all sorts of engines that have run well over one hundred thousand miles each without failure. How many engines have you owned that have run one hundred grand or more on stock pistons? Ive had several and didn't baby them either.

    Tom
     

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