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383 stroker or 350? What is it

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by zach78k5, Mar 11, 2002.

  1. zach78k5

    zach78k5 1/2 ton status

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    what is the difference. i am told that a 383 is just a 400 crank in a 350 block. is that correct. does anything else have to be changed? rebored? what is the benefit of a 383. Rather, what is the comparison. higher hp, torque. is the peak hp or torque occuring at different rpm range. any info would be useful. which should i go with?
     
  2. 55Willy

    55Willy 3/4 ton status

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    the 383 is a 350 with a 400 crank then overbored .030"
    you'll need the dampner and flywheel off the 400 as well, unless you get an aftermarlet crank then most are now set up to reuse the 350 parts.
    Compression depends on what pistons
    more torque, long stroke/forums/images/icons/cool.gif
    horsepower and torgue will always cross at 5250rpms.
    torgue gets ya rolling, horsepower keeps it moving.

    I'd build a 383.
     
  3. TopOff

    TopOff 1/2 ton status

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    If I had to do it over again, I would have saved my money and got some better heads...
    Just my .02

    Then again, I would probably always be wondering... how it would be if I had a 383. Now I know /forums/images/icons/smile.gif
     
  4. zach78k5

    zach78k5 1/2 ton status

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    well i have kick ass heads and i am replacing the crank. what is the horse power difference? the torque difference? where is peak horse? peak torque? i see that they cross at the same point, but what is the benefit to a 383 over a 350. if i have to rebore and replace pistons i want to make sure it is for good reason.
     
  5. outlaw612

    outlaw612 1/2 ton status

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    There is no replacement for displacement, more cubes=more power
     
  6. 4x4blazer

    4x4blazer 1/2 ton status

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    There is more than just reboring. The block itself has to be machined in a couple of places to allow room for the 400 crank to turn. Most good machine shops will know what has to be done.
     
  7. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    Hey 55willy, you are the first person that I have seen that also seems to understand that "torgue gets ya rolling, horsepower keeps it moving." Most people that you see post something on here about their truck always seem to be worried about HP. When I build a motor for a truck I am looking for large torque figures at low RPM's. Maybe someday they will also learn what it takes to make a truck move from a dead stop and also to pull hills and trailers.
     
  8. reddog64

    reddog64 1/2 ton status

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    how do you spell torque? I spell it 468... er that's how my truck spells it... /forums/images/icons/smile.gif
     
  9. Seventy4Blazer

    Seventy4Blazer 3/4 ton status

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    ah, but if you had 383 WITH better heads, then you would love it.
    Grant
     
  10. CaptCrunch

    CaptCrunch 1/2 ton status

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    A 383 needs to breathe... so heads are important. This is especially true if you want power over 4000 rpm. IMO the only stock gm head worth using is the vortecs, otherwise move up to bit larger port head... 180-190cc range.

    The other thing is the machining costs add up quick. I would look at a short block or long block setup w/ warranty. Will probably cost about the same as doing it yourself. One last thing is IMO a 400 would be better and cheaper. Only real additional cost is machining heads for the steam holes, but that isn't anything too pricey. The whole reason 383's were thought up/are popular now is because 400 blocks are getting harder to find in many areas of the country.
    Also don't forget the right combo on a 350 will do wonders. You can make 400 ft-lbs of torque pretty easily with a 350, Have seen dyno numbers up at 440 for a setup that doesn't care about hp figures.

    Whoever said they would rather have aftermarket heads... I agree. One of the old racers I hang out with says "Whoever has the best heads wins" and it is the truth.
     
  11. TopOff

    TopOff 1/2 ton status

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    Yeah, I built myine for reliability and HIGH torque figures. I LOVE to go rock-crawling. So I want HIGH torque at low RPMs. I also KNEW I would have the TH350 for some time. Of course I REALLY want a sm465 now. SO with an AUTO, wanting low RPMs and HIGH torque. I crunched the numbers and figured out want I want. I got an RV type cam basically, I figured with an auto and the rock-craling, and freeway speeds I will be doing I am better off getting ALL the torque I can from idle to 2500 rpms +. That is what I got.

    I get 440 lb/ft torque from 1200 RPM and it DROPS at 2800 RPM.
    ~300 hp I think at 3200 rpm. This makes ROCKIN' and Towing a breeze.... /forums/images/icons/smile.gif

    Looking at bigger better heads, I would only gain another 15 lb/ft and another 10 maybe 15 hp. Unless I change my cam...
     
  12. Zepplin

    Zepplin 1/2 ton status

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    I spell torque like; 496!
     
  13. muddin4fun

    muddin4fun 3/4 ton status

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    I've got a 383. It's a little stump puller and gets 13 m/gal /forums/images/icons/smile.gif. The truck will climb anything!

    I love it! Next up for it is MP fuel injection /forums/images/icons/cool.gif
     
  14. TopOff

    TopOff 1/2 ton status

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    Oh yeah, I get 14 mpg with Howell TBI. I was getting 15 MPG with my Edelbrock carb... weird.
    Edelbrock carb flooded going uphill.
     
  15. 79Beast

    79Beast 1/2 ton status

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    Nobody seems to be answering your actual questions, rather they are restating what they know about stroker motors. Build the 383. Put good (vortec, if it was me) heads on it. With a longer stroke, you will get more torque across the entire RPM range than with the shorter stroke. Your motor will not have the ability to run as high and RPM as the shorter stroke motor however, the RPM limitations of a stroker motor do not come into play for most of us "under 7000" guys. Your 350 block with have to be machined to keep the 400 crank from hitting the bottom of the cylinder bores. Your choice of cam, heads, intake, carb, etc will influence your power numbers and where they fall on the RPM chart. Done correctly, all other factors remaining the same, a 383 will make more power than a 350.
     
  16. Muddin_Mavric

    Muddin_Mavric Registered Member

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    You all spelled tork rong

    Its spelled ..... DIESEL !!!


    why do you think semi truck that are made to pull heavy loads are all diesels.
     
  17. zakk

    zakk 1/2 ton status

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    383 is a 400 in a 350 block bored over .030

    Compression will need to stay at 9:1 if you want to run 87 octane (or aluminum heads)

    My pick for cost and torque is a 350 engine w/ good heads and 6" rods. the longer rods improve the stroke ratio and will give you a flatter torque curve through the powerband. it will also let it rev a bit higher (IMHO...i don't like spinning 400 cranks out, almost all are cast and they are notoriously weak in the upper RPM's)

    Most 383's use the 400's rods, which are a measly 5.5sumthin' which is worse than the 5.7 350 rods which are worse than the Olds "Rocket" 6in" rods.

    If you are looking for that kinda power, go to a BBC.

    Last months Car (Chevy) Craft had an article where it broke down the cost per HP in a 383 SBC vs. a 454 BBC. to get about 450 hp each spent about $14.50 per HP. but the BBC obviously had more and lower torque numbers.

    just a ramblimg FYI...i need sleep...
     
  18. 84_Chevy_K10

    84_Chevy_K10 Banned

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    A 400 crank will not fit into a 350 block without turning the main journals down. Somehow all you 383 guys must have forgotten this because 383 cranks are cheap and easy to come by now.
     
  19. AKT K5

    AKT K5 Newbie

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    I've found that using a stock 350 motor and heads out of a '73-'76 camper special produce good torque for us budget buyers. These motors have the 176cc heads on them, since they where originally made for towing campers and trailers. This motor can produce 370 peak HP and I picked one up for $250.
     
  20. arveetek

    arveetek 1/2 ton status

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    <blockquote><font class="small">In reply to:</font><hr>

    You all spelled tork rong

    Its spelled ..... DIESEL !!!

    <hr></blockquote>


    /forums/images/icons/laugh.gif /forums/images/icons/laugh.gif /forums/images/icons/laugh.gif

    Casey
     

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