Bearing advise needed

Discussion in 'Street/strip 400/430/455' started by StfSocal, Apr 10, 2019.

  1. StfSocal

    StfSocal Well-Known Member

    Hey all,

    Question on bearings for you guys. I recently decided to ditch the stock rod bolts on my build and got the ARP rod bolts for piece of mind. Obviously I want to get them installed and then have the rods resized. The rods have already been balanced with the crank and clearances set (.0022). So I would just need to make sure that nothing changes in regards to that after resizing.

    Here is where my head is at, the bearings are basic federal mogul bearings, not sure on the size. Would it makes sense to maybe switch over to TA bearings for the rods and mains? Just the rods? Or run it with the bearings that are already in the build. These bearings were installed when the motor was built back in 2004. The motor never ran and since I bought it in 2009, I have been going through it and been changing things here and there.

    Next question is this, there are already cam bearings that have been installed. No idea what brand but likely not the fancy ones from TA. Would it make sense to pull them and swap for the dual grooves from TA for the added protection? I don't have a cam tool and would like to not have to buy one for a one time deal. However, since the TA cam bearings require specific installation, I am not sure how much i trust a shop to do it and hope it is done right.

    Thanks for the help guys,

    Scott
     
  2. Stevem

    Stevem Well-Known Member

    What part number FM Bearings are in the build now as they have a standard replacement and a performance series of Bearings.
     
  3. TrunkMonkey

    TrunkMonkey Well-Known Member

    If you change the lower bearings and have resizing done, it may well change enough on the balance.
    Consider a small change on the area with greater throw weight (the big end) will have greater effect than the same change with small throw weight, in regard to moment shift.

    As for the TA cam bearings, if your going to be in there and you are going to stomp on it down the road, it is about $200-$250 for the bearing tool and the bearings if you do the work.

    I had two sets of bearings installed incorrectly by two different shops, then did them myself. I also screwed up two bearings when I inadvertently left the washer that bears against the expanders after knocking out the bearings and put the tool away (leaving the washer on the counter) and did not have it when I went to install the bearings, they went in slightly off axis and I ruined them. Then I took the bearing tool apart to inspect it, I realized I left the washer out.

    Saying that, to say, if you do it yourself, maybe knock out the old and then put them back in to get the feel of the tool and familiar.

    It took me $40 and a week's progress to attend that bearing class... :p

    Unless your spending money on other machine shop work, it will be about the same cost to do them yourself.

    If you go with the TA bearings, the clocking at 3 and 7 all the way through as looking at the front of the block in the upright position.
    I used a sharpie to mark the bore and the bearings to keep them correct as the tool may twist a bit as you adjust the expander prior to driving it.

    Make sure you use the cone and keep things tight and loaded before that first whack on each bearing.

    I used a flashlight pointed through the gallery and oil passages to line up the cent ring between the two grooves on the bearing to the oil passages, and it set them properly in the bores.

    Given the benefits of the TA bearings, it's good insurance on the cost of a rebuild from a failed front cam bearing.

    My 2 cents.
     
  4. alvareracing

    alvareracing Platinum Level Contributor

    The bearing size should be on the back of the bearing. The bearing size is base on the crank journal size, if you mic the journals and the bearings you should be able to figure out the clearance. The big hole housing fit of the bearing on the rod should be the same as factory, if not the bearing will not fit right and pinch the journal somewhere, or not have the correct crush. The machinist need to have that big hole sized to whatever the book says it should be. I can't remember that exact number of the top of my head. As per the cam bearings, I won't run nothing but the T/A's or any other one that has the back grooves for the oil whole clocking. If your machine shop can put them in, just be sure they clock them correctly. Mark the location for them with a marker before you give them the block. Good idea to ditch the factory rod bolts, just hope all the machining and different bearings don't change your balance job. Most name brand manufacturer main and rod bearing should work. It doesn't have to be T/A specific. Hope I answer your questions.
     
  5. StfSocal

    StfSocal Well-Known Member

    Well looks like I was wrong on the brand. They are Clevite 77. Back of the bearing reads CB762P and then 10 82 010.
     
  6. alvareracing

    alvareracing Platinum Level Contributor

    nothing wrong with those, just get your clearances right. We have been known of buying multiple sets to get the correct clearances, they are not all exactly made the same. I've been able to get a few more or less tenths for that desire number.
     
  7. Bens99gtp

    Bens99gtp Well-Known Member

    In theory if the shop doing the rod work would measure each rods size, and get each rod back to that size bearing clearance shouldn't change. that being said adjusting bearing clearance by rod size is not the best way to it. either bearing size or crank size is a better way to adjust clearance.

    bearing choices over the last 15yrs has changed, I would look them all over very carefully if any scratches as all I would spend a few hundred and get new
     
  8. StfSocal

    StfSocal Well-Known Member

    Thanks all,

    Clearances were confirmed by another shop a couple years ago. Since then I’ve moved and using that shop is no longer feasible. That being said the clearances were .0022 for all rods and .0025 for all mains.

    I will look over the bearings closely for any imperfections. If some are suspect I’ll juts go ahead and change them all out.

    Looks like I’ll have to decide on the cam bearings. If i want to do it myself I’ll have to fork over coin for a tool. Not something I really wanna do at this point.

    Regards,

    Scott
     
  9. Bens99gtp

    Bens99gtp Well-Known Member

    Scott how much lift are you planning on running on that camshaft those dual feed cam bearings are really effective on all things but really needed on the high lift to keep the oil on the bottom side of the hand between the bearing if you're running a can that's in the 500 or lower there really might not be a whole ton of advantage to it the higher lift causes higher spring pressures was pushed down on the cam more and pushes that ooil wedge out from underneath of it
     
  10. StfSocal

    StfSocal Well-Known Member

    Ben,

    Camshaft i am going to be running is the TA290-94H and using factory rockers (1.55). So lift will be .476 & .486. Spring pressures were set within spec, i dont rememebr off the top of my head what they were. Obviously as time passes and if this engine proves to be a good runner, then that cam could always change. I don't foresee anything above .510 in the near future and could always change bearings later if the cam changes.
     
  11. 87GN_70GS

    87GN_70GS Well-Known Member

    I have cam bearing tool I bought but never used. I'll make you a deal
     
    Footbag and StfSocal like this.
  12. patwhac

    patwhac Well-Known Member

    Sorry to hijack, but I might be interested if the OP passes. Getting ready to do cam bearings myself!
     
  13. StfSocal

    StfSocal Well-Known Member

    Pat I’m waiting for more info from Scott, if I pass on the tool, I’ll let you know.
     
  14. patwhac

    patwhac Well-Known Member

    Sounds good! Let us know how it turns out either way, I think practicing on the old bearings like TrunkMonkey said is a good idea!
     
  15. StfSocal

    StfSocal Well-Known Member

    Ya trunk monkeys idea is good and I’ll definitely go that route.

    When are you looking to do your bearings?
     
  16. patwhac

    patwhac Well-Known Member

    Probably in the next 2 months. I still have to order my camshaft from Scott Brown, just saving up so I can buy the cam, lifters, springs, and bearings all at once. How about you?
     
  17. StfSocal

    StfSocal Well-Known Member

    Once I get a tool I’ll pop the ones currently in, out. Then I can find the size and order the TA bearings. So probably within the next month.
     
  18. StfSocal

    StfSocal Well-Known Member

    Pat,
    I’m gonna pass on the cam bearing tool that Scott has. Got a coworker who has one I can borrow.
     
  19. patwhac

    patwhac Well-Known Member

    Good to know! Hopefully I can make a deal and learn the ways of the cam bearing. I am going to attempt to pull the old cam out today actually.
     
  20. StfSocal

    StfSocal Well-Known Member

    Hey all,

    So I found a good machine shop near me to get the ARP bolts installed on the rods.

    However, I am now freaking myself out on the whole balance thing. I need to check the crank to see if it was internally balanced (look for slugs in the counter weights right?) or if it is still external. I really don't want to have to spend huge money on re-balancing but don't want the thing to come apart. I doubt this motor will see north of 5500RPM often (Single plane with a flat tappet TA290-94H) and don't plan on racing it (maybe a stoplight here and there).

    Am I overthinking this? Should I just take the pistons and rods into the shop with the bolts (along with crank to ensure clearances are still good after bolt install & resizing) and have them advise?

    Thanks,

    Scott
     

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