Options for Compression Ratios 1GR

Discussion in 'F/I Mods & Tuning' started by iniazy, May 27, 2014.

  1. iniazy

    iniazy Active Member

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    I would imagine the gasket would be necessary to provide leverage to hold the open-deck cylinders in place, and to avoid distorting their surface.
     
  2. Torspd

    Torspd Moderator
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    I just confirmed that yes the head gasket is supposed to be used between the torque plate and deck of the block. To simulate everything as it should be when all torqued down.
     
    #42 Torspd, Sep 11, 2014
    Last edited: Sep 11, 2014
  3. iniazy

    iniazy Active Member

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    Guys I'm bringing this thread back to life, I am preparing my shopping list for rebuilding my old 1GR. I was looking at head gaskets, there are varying thicknesses. I think the thicker gaskets are for if someone wants to drop engine compression without replacing the pistons, am I right?

    If that's the case, then the thinner the head gasket the better, as it probably would be stronger and less likely to blow. Is that so?
     
  4. Torspd

    Torspd Moderator
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    They varying thicknesses are for more than just dropping compression. If the heads and decks are machined, and you want to maintain the stock compression ration, then a thicker set of gaskets would be needed. To compensate for the removed material. Or even to aid in a little extra room for valve relief. If just adding thickness to attain a lower compression ratio, then the math would need to be done to make sure the proper thickness is used to achieve that ratio, and not a undesired or unknown ratio.
     
  5. XMPLRY808

    XMPLRY808 Active Member

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    Yea I wouldn't get a thicker head gasket if not needed
     
  6. iniazy

    iniazy Active Member

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    Got it, thanks guys. Makes sense.

    What about valve springs? Is it always the stiffer the springs the better? I know stock springs can only handle so much boost, but not sure what springs to pick for my levels of boost.
     
  7. Torspd

    Torspd Moderator
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    Stiffer valve springs are a worthy upgrade, if you are in there, and plan on turning up the boost. It will prevent valve float. If you did happen to buy cams, with more lift, upgraded valve springs are REQUIRED. Rob tested that with his set. Turning the cams by hand deformed the OEM springs and they would not return to full height.
     
  8. iniazy

    iniazy Active Member

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    So how stiff should I go? I imagine if they're too stiff they will rob some power. I see there is 61 lbs pressure (while closed), 71, and 120. Surprisingly the 120 is cheaper than the 71.
     
  9. Torspd

    Torspd Moderator
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    Partially depends on if dual springs, or single, and if adding lift from the cams. You're not getting cams correct?

    Hypothetically if you do, would you go for a set which requires a lot of head work, or none?
     
  10. iniazy

    iniazy Active Member

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    I don't think I'll go for any aftermarket cams for now or head porting. I may later in the future.
     
  11. Torspd

    Torspd Moderator
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    The point being, is that if you do head work, and get springs, get a set that will work for any potential future mods. To prevent having to purchase another set down the road.
     
  12. XMPLRY808

    XMPLRY808 Active Member

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    You won't be able to tell at all that the stiffer springs will rob power
     
  13. iniazy

    iniazy Active Member

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    OK so I'll get the stiffest springs there is. Thanks guys for the great help.
     
  14. Gadget

    Gadget Well-Known Member

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    Stiff springs eat HP.

    Unless you are going to be spinning the engine really fast or using a high lift cam and need to worry about spring bind and fatigue, there really is no benefit in putting in real stiff springs.
     
  15. Torspd

    Torspd Moderator
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    That is the benefit of dual springs.
     
  16. XMPLRY808

    XMPLRY808 Active Member

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    On my Honda motor (no torque at all lol) I installed stiffer springs and didn't notice any loss on my low end.. Installed springs just for higher boost but yeah dual valve springs ftw!
     
  17. iniazy

    iniazy Active Member

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    Does anyone sell a Master rebuild kit for the 1GR with forged pistons and rods?

    Seems rebuild kits are sold with standard cast pistons,.

    How is Dezod reputation for engine rebuild parts? Are they as reputable as LCE?
     
  18. NHXRUNNER

    NHXRUNNER "New Hampster"
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    Talk to akakrill....his rebuilt engine just showed up the other day. He did tons of research. :top:
     
  19. Torspd

    Torspd Moderator
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    Dezod doesn't do it anymore.

    LCE probably does. They used to source the components and do complete rebuilds. A few members on here have had them done, and many in Saudi Arabia and the UAE.

    Or you can order all of the parts A la carte.
     
  20. iniazy

    iniazy Active Member

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    I'm really happy with the support and knowledge of LCE, I think I'll buy from them.
     

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