Yeah the title was meant to be funny, but I've got a serious question.

I did a few searches and couldnt really find anything I could apply to my situation. I'm new to this whole game, you're going to be hearing a lot more from me as I get farther into this, but I'm trying to learn!

I've got some Vortec 350 heads I bought a while back. These:



They've got guideplates on them. Is there any way to tell if they're hardened or not? From what I understand that's going to make a fairly significant difference in regards to pushrods and rocker types, but I dont know if assuming they're hardened is a safe to assumption or not.

Also, like I said I'm new to this, but what size studs do I have? Im not sure what I'm supposed to be measuring to get the stud size for the rockers I need. I cant find anything obvious, unless it's referring to the size nut that goes over the threads, in which case I wouldnt even know how to figure that out as I dont have nuts laying around to try... I dont know if they're stock or not either, so is there any easy way I can find out? Certainly there's something obvious I'm missing here... Unless the sizes are interchangable as long as they all match?

And are there any other things I need to pay attention to as far as compatibility goes? I figure I'll stick with stock ratios for the sake of cost and simplicity.

Anyway, sorry for the silly questions I'm just trying to learn. It'd be so much easier just to do a rebuild of the 305, but not nearly as much fun...

 

What brand are the guide plates? If they're GM, they're not hardened; if they're anything else, they probably are.

The size of the stud refers to the diameter of the threads. 3/8"-24 is stock. 7/16"-20 is the larger size. You can get nuts at the hardware store to try if you want. Those look like 3/8" to me.

 

I have no idea, but these heads aren't stock at all, though. But I dont know if 906/062 heads came with guideplates stock. If they didn't then I would assume these are aftermarket.

 

No, they didn't come with them.

They may or may not be aftermarket. You can buy guide plates from GM. Don't "assume" anything.

Look at them. The maker will be stamped somewhere, or at least a part # which can be just about as useful.