Speed Pro Rod Bearings

[texasquake]

:?:
Replacing the rod bearings on my SBC. New Speed Pro bearings have a camfer edge that can be installed near the "slot" on the rod cap or on the opposite side. Does it matter how the camfer portion of the bearing faces in the rod cap?
Thanks

[wayne petty]

rod bearings will only fit in the rod in one direction do to the alignment tang...

if the upper or lower bearings are different that is strange..



please post the numbers off the end of the box...   for more info .,.,

[texasquake]

Wayne, I understand the alignment thing. The issue is, I have half of the bearings with the camfer on the side of the alignment notch, the other half have the camfer opposite of the alignment slot. Interesting, huh? Box number - C8-7100CH  10 Duroshield  .010 undesized.

[wayne petty]

thanks for the part numbers...  it helped a bit...

i still think a call to speed pro might be in order...   i cannot seem to find a current catalog online that describes the bearings... other than they are serious race bearings.. built with decent materials...  

i am also wondering if the relief in the bearing shell is a reserve for oil...

or a place for the oil to be spread out on the bearing surface by the rotation of the crank surface...

according to what i read ... the mains use a wave shape to the thrust bearings so the oil film is allowed to build then forced under the thrust bearing face ... this would provide in my thoughts a thicker film for the thrust face...   this might be what they are doing with the rod bearings...

i have thought about doing that with rod bearings..   putting a wedge area on the rod bearing so the rotation of the crank will grab the oil and force it into the narrower and narrower area which raises the film pressure between the bearing and the rotating crank journal...

got a picture of  the face of the bearing... if so... since the squirter side is up ... that gets a shot of oil as the oil hole passes to spray oil up into the various parts...  my thought would be to use it on the other side... as a reserve wedge...


this is just my opinion    i did not read anything other than the article/ad a few years ago about the thrust bearing surface shapes...

since these are used by professional race teams... they might be designed  with feedback from the engine builders at the teams so they don't have to modify uncoated bearings.. then send them out for coating...  having the production line modify the bearings to the racers modifications saves time and money for the racer and makes them a more desirable product for the professional race engine builders...

[Crosley.In.AZ]

Usually the chamfer goes against the crank edge for the rolled radius area so the oil is not locked in and can freely flow out.

[wayne petty]

tony.. that makes to total sense      i was thinking of the parting lines..

one side of the bearings have a chamfer .    that is to clear increased sides of corners ground into the crank journal..   larger corners ground in increase fatigue strength... and prevent cracking...

if conventional rod bearings are installed on a large radius crank... they will rub metal to metal...     some rods even have a slight chamfer on one side to match the bearings...  and to clear the crank...

again.. thanks tony for pointing to the side in stead of what was right in front of my



so the chamfered faces  fit in the rods with the chamfer facing away from the other rod on that journal...



here is a link to a picture of the chamfer on the rod..
http://www.bustedcar.com/2006-03-07_045.JPG

i did not find any decent picture of the chamfered edge of the bearing

after i posted and was closing windows... i ran across this link...

http://www.turbomagazine.com/tech/0610turp_castillo_crankshaft_service/index.html

many will find it interesting...


wayne