Hi, I probably already know the answer to this but I'm wondering what others have to say. My rocker arm assemblies for my 426 hemi are drilled out for 1/2" head bolts. They are not the assemblies that were on the engine the last time it ran. My block is still the standard 7/16". First off, will these work with 7/16" head bolts and maintain proper oil pressure? If not, does anybody know of a crafty fix to try before I search for four oiler rocker stands? thanks in advance, Rob

I want to add that I have a CNC and a few endmils at my disposal so I could machine a bushing for each stand - but I'm hoping somebody has used this combo with success first.

I would fix it
The stock steel stands where machined for them,7/16 head bolts with washers and the stock head bolt shoulder size, not bushed, if I'm remembering correctly
All the after market stands I've seen had bushings in them

The larger hole will have no effect on oiling as long as you did not drill the lube passage within the stand.

Thank you for the replies Cab_Burge and Transman. It doesn't appear as though the oil passages in the stands were drilled too. Does anybody know the stock size of those passages so I can measure mine to be sure? If they were not drilled out as well, then I should be good to go.

A .250” drill bit fits nicely in those oil passages.

Everything will probably work fine. I would be more concerned with that washer on top having to span a bigger hole. I would be inclined to use this opportunity to acquire a set of those sexy anodized aluminum rocker stands for 7/16" head bolts.

Transman, thank you, I will try one today and hopefully it fits just right.

rickseeman, that was on my mind too. If I had the additional funds I would buy a nice sexy set...lol I'm going to look at McMaster-Carr and try to find a hardened - larger diameter washer with the same ID for just that purpose.

I know propel that have had problems running the sexy aluminum stands they flex on the street