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so sad

Discussion in 'Trucks and Trailers' started by beerandcope, Apr 9, 2001.

  1. beerandcope

    beerandcope LawnSite Member
    Messages: 36

    well its a sad day in 350 land as mine has died once again. i am finally putting it to sleep. can anyone give me some perks and or problems with a 400 small block?
    what kinda carb should i run? will it give me trouble with a 350 turbo tranny behind it? or will it give me trouble period??? thanks in advance for your input

  2. 85w/350

    85w/350 LawnSite Member
    Messages: 244

    I havent heard anythign bad to be bashing a 400 but the way I look at it:
    So many parts.....
    So many still avalible.....
    So many still out there running well.... :)
  3. mike reeh

    mike reeh LawnSite Member
    Messages: 229

    400sb is a great motor. if you have one already available, then I say go with it. it will bolt up to just about anything that any other small block will, and take all the same bolt on parts. carb? i would recommend a q-jet but if youre into the square bore carbs, any will do.. id probably run a 650 or 700cfm max especially on a mild motor.

    you wanna make sure your cooling system is in excellent shape.. some say the 400 creates a lot of heat.. one thing i know is that they are a little more susceptible to heat damage so you dont want em getting hot in the first place..

    i run a sb400 and probably will always, ive had real good luck with mine..

    thats my opinion

  4. 75

    75 LawnSite Senior Member
    Messages: 992

    OK, here's my opinion(s):

    To get the 400 cid into a small-block package, the cylinder bore had to be increased. This means there is no water jacket between adjacent cylinders ("siamesed" bores) which is why the 400 is more susceptible to damage from overheating. As long as your cooling system is in good shape & you pay attention to the temperature gauge, there should be no problem.

    400 is the same (externally) as a 350, so bolting up to the T350 trans will be no problem, and the transmission should handle the 400 engine OK.

    Just remember that the 400 is balanced externally - they use a special flywheel/flex plate and harmonic balancer because with the extra bore & stroke stuffed into a small-black package, there isn't much room for counterweights on the crank. The 350 flywheel/flex plate & balancer will NOT interchange.

    As for carb, I like the Q-jet, especially for everyday driving.

    The 400 is more of a "torque" engine, not as much top end/RPM as some of the other members of the small-block family. In my opinion, torque & low/mid range power is what you want in a truck - at least one that's used as a truck!

    If you have or can get a 400, by all means use it! Since it'll bolt right in where your 350 was, it should be a simple swap and if for any reason it doesn't work out (always check out a used engine thoroughly if you go that route!) a 350 can go right back in.
  5. John DiMartino

    John DiMartino LawnSite Silver Member
    Messages: 2,555

    For a truck the 400 is the way to go,torque,torque and more torque.I replaced 350's with 400's twice-both times the truck went from barley adequete to super truck-capable of topping big hills with no problems at all.
  6. 75

    75 LawnSite Senior Member
    Messages: 992

    Just wondering John - I know this is going to vary a lot from one area to the next, but how readily available are 400's? I don't see them too much around here in the used marketplace - maybe those that got 'em, hoard 'em! :D

    My 350 does fine (4:10 gears help for pulling power, but are lousy for mileage!) but the extra 50 cubes & more torque are always good. Changing an engine in an old truck like mine is real easy, so I'd gladly drop a 400 in some day.
  7. Alan

    Alan Member
    Messages: 1,185

    If my memory is right, I think the 400 made more torque than the old 396/325 hp did. And made it at lower RPM as well. If I can ever find a decent late 70s chassis to build the way I want it WILL have a 400 in it.
  8. beerandcope

    beerandcope LawnSite Member
    Messages: 36

    thanks for all your input guys. im leaning more and more toward putting a 400 in my truck. just a few more ?'s can anyone recomend a tranny to back it upand possibly a transfer behind that? thanks again

  9. 75

    75 LawnSite Senior Member
    Messages: 992

    Here's my 2 choices for trans/T-case:

    Manual: 4 speed/205

    Automatic: T400/205

    I realize these may not be the best combos from a gas mileage standpoint, but I like to build strong!
  10. mike reeh

    mike reeh LawnSite Member
    Messages: 229

    for tranny + transfer case its personal preference.. 205 is a strong beast, 203 is a good case too and you can get a 2 wheel lo-range with the part time kit, which I really like, plus they're cheap.. turbo400 automatic is a beast but it takes more power to turn and is more expensive than a turbo350.. turbo350s can be built extremely strong, too. 700-r4 is an excellent choice also, with its overdrive.

    let us know what you choose


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