Camshaft Thrust Plate Bearings?

Discussion in 'General Ranchero Help' started by colnago, Apr 4, 2019.

  1. colnago

    colnago In Overdrive

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    I was cruising the Comp Cams site today, and ran across their "Camshaft Thrust Plate & Bearing set," for improved spacing and wear protection at the front of the block, blah blah blah. This is the first time I've run across something like this. I take it that this is really for the hot rodder who has everything, and not a must-have for us mere mortals. Pretty sexy little item, but I think $120 in my bank account is sexier. Anyone use one?

    Joseph
     
  2. pmrphil

    pmrphil In Overdrive GOLD MEMBER

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    never even give it another thought, not anything for a street engine. Have only installed 2 in all the years I've been in business building engines.
     
  3. colnago

    colnago In Overdrive

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    I read one review on Summit that said, "I have roller rockers, I have roller lifters, and I have roller thrust bearings, so I have a complete roller engine!" I had just never heard of such a thing. Mostly, it got me wondering about any front-to-back movement of the camshaft.

    Joseph
     
  4. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    A proper timing set has so little slop, that as long as the cam install (including the cam plug at the back of the block) was done correctly, there should not be any physical contact. Only a very-high-performance engine would have to worry about that.
     
  5. Hillbilly

    Hillbilly In Maximum Overdrive

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    I can tell that you avoided GM engines when you could Andy. You missed out on those pitiful small block Chevys with mis-aligned cam bearing bores. Those jokes had to have something retro-fitted to keep the cam from walking forward or to the rear. Due to the firing order most of them required a button of sorts installed in the front of the cam that ran against the inside of the timing chain cover. On the ones that walked to the rear a roller thrust bearing was put behind the cam timing chain gear where our Fords had a thrust plate up front that kept the cam in alignment.
     
  6. colnago

    colnago In Overdrive

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    Don't some of the Ford roller camshafts also use a button in the front to keep them aligned?

    Joseph
     
  7. Hillbilly

    Hillbilly In Maximum Overdrive

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    All I have ever seen have that common thrust plate bolted in behind the cam sprocket. It may exist but I haven't seen one yet.
     
  8. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Yes, I have dealt with 'cam buttons' because I did a replacement of a FWD 3.8 where the cam gear and stretched chain ground through the timing cover, no cam button, so the whole engine was ruined. I had to hit up the Pull-my-Pud yard for a suitable core.
     
  9. colnago

    colnago In Overdrive

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    I thought I saw something to keep roller cans from wandering, and running the cam lobes into the next lifter. I think Edelbrock makes a special timing cover to keep the plate on the water pump from flexing. Maybe I saw it on a Chevy site, though.

    The more I read, the more I learn that the less I know.

    Joseph
     
  10. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    On a roller cam, the lobes are not cut the same way as the lobes on a non-roller (I'm not using the word 'flat' so you understand). The non-roller, whether with solid, liquid or hydraulic tappets, has a slight 'crowning' to each lobe, and each tappet has a very slight convex to the bottom. This allows half the tappet bottom to rest on the lobe at an odd angle in order to spin the tappets in their bores. You do not want to spin the tappets on a roller cam, of course, so the lobes are square across the face, and devices on the tappets prevent them from turning inside their bores.
     
  11. pmrphil

    pmrphil In Overdrive GOLD MEMBER

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    No.
     
  12. pmrphil

    pmrphil In Overdrive GOLD MEMBER

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    Yes, that is on a Chevy. Kind of a common problem with high volume/high pressure oil pumps.
     
  13. pmrphil

    pmrphil In Overdrive GOLD MEMBER

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    You are correct, not on a small block.
     

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