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427 small block?

Discussion in 'The Garage' started by blazin_blazer, Feb 28, 2007.

  1. blazin_blazer

    blazin_blazer 1/2 ton status

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    i read an article one time where they used small journal rods(like in my '67 327) and bored a 400 .060 and offset ground thr rod journals on the 400 crank for the 2'' rod end thus creating a stroked engine. i've talked with several local machine shops to no avail. any1 know a machine shop that would know what i'm talking about and also perform the work? the closer the better but any shop that knows what they are doing would work ....uuhh hmmm 4x4high....i know you the man for this!
     
  2. DEMON44

    DEMON44 Low-Tech Redneck

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    Sure you can a friend of mine has a 434 SBC. stroked 400. its dyno'd 500hp carb'd, no juice.
     
  3. boz42

    boz42 1/2 ton status GMOTM Winner

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    i would think using an old 327 rod would cause a rod length to stroke issue, but u can get them aftermarket in longer lengths.

    i did the same thing to my caddy 500. offset ground the crank journals from 2.500 to 2.200 & used a 6.800 bbc rod. had to buy custom pistons. for the crank work i used the crankshaft superman. thier shop is hear in memphis & they are good at what they do. i wound up w/ a few more than 540 cubes.
     
  4. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    You can weld the crank so that it can be offset ground to effectively make a stroker using the factory rods. You will have to have a piston custom made though to relocate the wrist pin in the proper position otherwise the piston will come out the top of the bore. The same thing can be accomplished by using a small journal rod like you heard but once again you will need to have p[istons custom made. It would be cheaper to just buy a stroker crank and the required off the shelf pistons.
     
  5. blazin_blazer

    blazin_blazer 1/2 ton status

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    any idea who has these parts or part #'s. the small journal 327 rod is 5.7 like a large journal just the wrist pin in the piston is higher. tell me where to find off the shelf parts to do this? how would you build it?

    they didn't weld the crank...they just offset ground the 400 crank the .100(the difference in a lg journal and smal journal rod)

    boz...who is this superman crank in memphis..i'm only about 1 1/2 hr away!

    i want a 427 sbc! and run the 427 badges to mess with peoples head!

    i've read that nascar use a 1.88 rod journal in some of their motors to get more stroke out of the crank
     
  6. blazin_blazer

    blazin_blazer 1/2 ton status

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    i'm out over and out have to study for a chem test and a bible test! goodnight all
     
  7. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    small journal rods are still 5.7" center to center. Custom pistons will have to be made. Also i forgot you were asking about offset grinding a 400 crank but it can be done.
    The small journal rods use a smaller rod bolt which is weaker.
     
  8. 1979jimmy350

    1979jimmy350 1/2 ton status

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    you can get 427 small blocks form world, they even make a 454 small block, or you could go with the LS7 thats a 427 small block
     
  9. superwrench

    superwrench Registered Member

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    There are several companies that make off the shelf pistons for this type setup, depending on how much they offset ground the crank. The piston is not the problem. Off set grinding a crank can be done, but by the time you get done welding it up and offset grinding it, you have as much in it as just buying a stroker crank already made. Plus the fact that you still have a cheap quality crank when done. I have managed to offset grind one to a 3.825 stroke with out welding it but it is hard to find a stock crank good enough to do that to. Also it changes you oil degrees in the crank and location, and you usually have to cut the counter weights down, some thing most people and crank grinders forget about. The stock small journal rods when properly redone will handel a fair amount of horse power and rpm on a regular basis. You can also buy these as an aftermarket rod. On big stroker motors, I use longer rods to eleminate side load on the cylinder. Dont forget that you have to clearence the block in these motors as well. You need to grind out in the pan rail area and down it the cam area so youre rods dont hit, not only the block or the cam. Tha last thing you should do is add hard block to the bottom off a stock block, not alot just up to the soft plug holes to add stability to the bottom of the block, and it tends to make the block run hotter some.
     
  10. blazin_blazer

    blazin_blazer 1/2 ton status

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    4x4high apply some of your mathmatical wizardry to what i'm talking about.
    A .060 400 block with the crank offset ground .100. reconed sj rods w/arp bolts. Would you gain .100 more stroke or would it be like a tire and you only gain 1/2 of the offset? thanks Rufus
     
  11. 71 Blazer

    71 Blazer 1/2 ton status

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    Gm performance parts has a small block that can be machined out to 500cubic inches, its called the LSX. 6 bolt main, handels up to 2500HP. Crazy.
     
  12. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    I talked with my crank grinder this morning and was told that you can only offest grind a crank .045" for a total gain stroke of .090" making it a 3.840" stroke instead of a 3.75" stroke using the small journal rods.
     
  13. blazin_blazer

    blazin_blazer 1/2 ton status

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    what limits the amount you can offset grind the crank?
     
  14. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    The size of the original journal. You can weld the crank and get more but most crank grinders won't weld that much on a cast crank. Besides, it is cheaper to buy a storker crank than to offset grind the original 400 crank. You do realize that you have to remove .200" from the main bearings in order to install it into a large main 327/350 block.
     
  15. blazin_blazer

    blazin_blazer 1/2 ton status

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    yes, its going to stay in a 400 block, so if its the o.e. size that limits you...thats why you see the smaller ''big'' end like the 1.88 or 1.87 so it can obtain the ability to gain more stroke

    so there is a limit there where the more you stroke the motor the smaller the rod end has to become to stay within the confines of an original sized crank?

    otherwise so the inside doesn't get to small as not to be there, does that make any sense?
     

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