350 rebuild questions.

Discussion in 'Small Block Tech' started by Juze86, Nov 9, 2015.

  1. 8ad-f85

    8ad-f85 Well-Known Member

    Which ones won't clear?
    How much does it look like you'll have to remove and from where?
    The amount removed will vary depending on cam indexing (degreed position).
    How much slack in the timing chain?
    How much valve spring pressure and anticipated cam flex, based on which cylinder's lobes interfering?
    A generic question gets a generic response.
    Answers will vary from .050-.070" minimum, depending on builder's preference.
     
  2. DauntlessSB92

    DauntlessSB92 Addicted to Buick

    If you haven't degreed your cam yet you may not have clearance issues. The Buick 350 rod to cam clearance is pretty tight. Even with stock rods you will hit the cam if it's not degreed. I would try your best to get things lined up before checking how much material you may need to remove.
     
  3. Juze86

    Juze86 Well-Known Member

    I have not checked all yet but at least number 2 hits on number 1's intake lobe, so propably 4, 6 and 8 will hit also right? If I advance it will be bit worse. Mike from TA told me .060 clearance should be fine.
     

    Attached Files:

  4. Juze86

    Juze86 Well-Known Member

    Compared to stock rod:
     

    Attached Files:

  5. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    To add to the above, with you wanting to advance your cam may give you the clearance you need because when the cam is advanced it will clear the cam more, retarding the cam will give less clearance. GL




    Derek
     
  6. Juze86

    Juze86 Well-Known Member

    I checked that in all 3 possible timing settings and 4 degree advanced was worst, 4 degree retarded was best.
     
  7. DauntlessSB92

    DauntlessSB92 Addicted to Buick

    Do you have some more info on these Rods? I was not aware that TA was selling custom 350 steel rods. I thought they only offered aluminum rods at about $1000 for the set. Still kicking myself for using capscrew rods instead of going custom.
     
  8. Juze86

    Juze86 Well-Known Member

    Id like to hear opinion on this.

    You can get these from TA or from http://www.campbellenterprises.com

    Stock dimensions except .005 shorter, bushed pin, cost around $600.
     

    Attached Files:

  9. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

  10. Juze86

    Juze86 Well-Known Member

    Make rods to fit is not big deal. Im now more worried I only have .0015 oil clearance for connecting rods, and .002 is recommend minimum right? Is it .0015 too tight? I measured them with plastigauge so I have to go machine shop to make it sure and maybe get journals polished little bit.

    Lhetetty minun H60-L04 laitteesta Tapatalkilla
     
  11. 8ad-f85

    8ad-f85 Well-Known Member

    Not to discourage...
    Typically the crank is ground last, to set clearances (I recall you had made changes along the way though...)
    It's not recommended to attempt to create more clearance with a crank journal polish, as very few can do it without causing further problems.
    I'm offering no recommendation on appropriate clearances.

    I would try a different bearing or grind it if you have a good crank fellow...if you think you need more clearance.
     
  12. Juze86

    Juze86 Well-Known Member

    Machine shop checked clearances and all were between .002-.0023 so Im good to go.

    Lhetetty minun H60-L04 laitteesta Tapatalkilla
     
  13. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Safe clearance should be .050" for your rod to cam clearance.

    As for you wanting to advance the cam an extra 4*, I have been told that doing that will only lower your useable power range that the cam is designed for and not really giving you more low end, requiring higher octane. You can try it installed by what it calls for and if you're not happy with it you can try it 4* advanced in the car. If you decide to change the setting later though, make sure you have cam clearance both ways. In the mean time enjoy running cheaper lower octane fuel until you decide you think you need 4 more degrees. GL


    Derek
     
    Last edited: Jun 7, 2017
  14. Juze86

    Juze86 Well-Known Member

    Tried to degree cam today and ended up 112 ICL. Never done that before so probably I did something wrong, or is it possible that cam is 4 degree off? I'll have to do it again.
     
  15. Juze86

    Juze86 Well-Known Member

    Looks like cam really was 4 deg off. I advanced cam by 4 and double checked ICL and result was 107,5 so that is where I'll leave it.

    Also made clearance for rods and cam, needed to grind cylinder 1 , 2 , 4 and 5 rods.

    I noticed passenger side rods are not center in piston, could this be problem? Unless they don't hit to pistons it's ok? Driver side is much closer to center.
     
  16. alec296

    alec296 i need another buick

    The cam has been 1 degree off by other users. So your advanced 4 . Should be fine unless your compression is high. Then dynamic compression will be high also. Piston rods should be ok. They will be offset some. It allows for 1 piston to work both sides with clearance
     
  17. 8ad-f85

    8ad-f85 Well-Known Member

    If your dynamic compression is a tad high, lower your air intake temps along with your water jacket temps...use wider exhaust valve seats with full contact (not interference angle). This stuff is alone worth several octane #'s of knock resistance (not points, whole #'s).
     
  18. Juze86

    Juze86 Well-Known Member

    My DCR will be 7.3:1, is that high? I've tought it could be closer to 7.7:1 - 7.8:1.

    Here is number 1 and number 2 pistons and rods:
     

    Attached Files:

  19. Juze86

    Juze86 Well-Known Member

    If I understood this right when I advanced 4 deg Im now at 108 ICL, and that how it says on camcard it should be.
     
  20. DauntlessSB92

    DauntlessSB92 Addicted to Buick

    I know this sounds like a silly question but is it possible that the rods are installed backwards?

    I made that mistake during my build. I was unaware that the Buick 350 used offset rods. I asked several people which way to install them and I got hung up on which side of the rods were chamfered and where casting dot on the rod should point. I didn't consider the offset of the rods though.

    When I installed the pistons in the motor the rods were very close to one side of the piston. It appeared they would have to be clearanced to fit or possible that the pistons were directional (no markers or instructions stating so).

    I paid a machine shop to flip the pistons on the rods as one side had more clearance than the other. After I did this I realised the rods were offset and I installed them accordingly. All rods were centered in the bore once that was done. A simple thing to overlook but not something that is always mentioned when building an engine with offset rods.

    I'm still really jealous about those steel h beam rods. I had no idea they existed till I read this thread. Now I have to find out how much abuse a capscrew rod will take.
     

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