IMO, the text above explain the carnage...just pay atention to how the factory restricted the oil flow to top of the engine:SilverXJ wrote:
When primed oil comes up throught the rockers quickly. And its not just a trickle. My machinist thinks that is where the problem lies. However, many people run this combo and don't have issues. I compared the stock pushrod and rocker combo's holes. The stock pushrod has a .095" hole, where the ones I am using have a .088" hole. The stock rocker has a .064" hole, where the Harland Sharps I am using have a .080" hole. Another difference is that the stock hole in the rocker is offset more to the pushrod side of the rocker. I have also been through 3 sets of lifters on the 3 cams. The comp cam had the comp lifters, the Isky cam had the Johnson lifters, and the Clay Smith cam had the generic lifters that I have seen marketed under different names.My machinist recomends I go with the stock lifters. However i have a few problems with that. 1) cost, 2) where are they made, 3) it has a small hole into the body, but the hole going to the pushrod seat is the largest of the bunch. Wouldn't that have a tendancy to bleed the lifter if more oil is going out through the larger pushrod hole than the lifter can refill through the body hole?Code: Select all
Lifter Body inlet Pushrod seat Comp .098" .079" Johnson .089" .078" OEM .052" .095"
I asked him about running a restrictor pushrod with a .040" restrictor and he agreed with that.
1- The body inlet of the OEM lifter is the restriction because it is the smallest orifice.Doesn't matter if the pushrods orifices are bigger than that.
The restriction you are thinkin to do ,already is in the factory lifters.
You should get they because you need the oil restriction at the same point of the main gallery ,otherwise th oil will scape through the valvetrain lash.
2-The stock rocker oil hole is offset for the same reason : Time the oil flow through the pushrod to increase even more the pressure at main galley.
Take care of these problems and check again the oil pressure with a drill. About the oil hole on new rockers,if it can't be modified, install a restriction into it or preferably at the pushrod end.
Hear your mechanic he is right, but I'd not groove the cam journals.
Anyway, is very strange the actual lifters are sending that much oil to the top...but...
Keep us posted about how this problem is solved;