345 heads on an IC392?

Discussion in 'The Skunkwerks' started by Zorak, Jul 26, 2020.


  1. Zorak

    Zorak Farmall Cub

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    hey, first post so here i go...

    i have a 1978 Scout2 with a 345A, i am looking to build a 392 short motor and fit my existing 345 heads, Isky cam and RPT alloy inlet.
    my question is as the IC 392 is fairly available, can that block be easily modified to suit the non IC 345 heads, or the heads be modified to suit the IC block?

    thanks
     
  2. Jeff Jamison

    Jeff Jamison Lives in an IH Dealership

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    Cant be made to work,the cooling passages are different,it would work with an older 392
     
  3. jeff campbell

    jeff campbell Lives in an IH Dealership

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    Yup.non improved cooling 392
     
  4. walkersscout

    walkersscout High Wheeler

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    Yes it works with non IC. There is no advantage though. You get a smaller combustion chamber for higher compretion, but you lose the bigger valves. You will hear lots of mumbo jumbo about improved bottom end or more torque, but from experience it felt like a little bit of a loss. The one thing you do lose that is benificial is the propensity of the 392 heads cracking.
     
  5. 1975IH200

    1975IH200 Y-Block King

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    If you want to increase the compression ratio of an IH SV-8 engine:
    a) Zero deck the block.
    b) Mill the heads.
    c) Instal the correct pistons.
    It's that simple.
     
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  6. Zorak

    Zorak Farmall Cub

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    thanks for the replies.
    there are a few reasons for wanting to keep the 345 heads, main reason is i already have modified the ones i have, another is the engine wont see high rpms so the smaller valves wont be a problem. although thinner stems would be desirable, also I had read the 392 heads have a different valve angle than the 345, but i don't know if this is correct.

    i have been offered a 392 that was a warranty recall due to overheating issues, the engine was completely stripped and put into boxes about 35 years ago. i haven't seen the engine so i can not confirm if it's an IC version or not. Was the IC 392 released in the 1970's or 1980's?
     
  7. Zorak

    Zorak Farmall Cub

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    i know this is the difference and wondered if anyone had welded and moved the location of the cooling galleries to suit
     
  8. tdc

    tdc Dreams of Cub Cadets

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    This one is a 1973 392 improved cooling. It will power a Scout ll soon.
    392ic 7.4.2020.jpe
     
    Last edited: Aug 2, 2020 at 2:30 PM
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  9. Zorak

    Zorak Farmall Cub

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    are you installing the engine as is, or planning to do some work to it first?
     

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