Just a sticky note for people that are building a new World/Mopar Iron Wedge block and Edelbrock RPM heads. The oil drain back holes in the heads are completely blocked by the beefy/additional cast iron in the valley. Im helping a friend with his 540" street engine and ran into this when I was setting the heads on. Im fairly certain that grinding or drillng the block in that area wont be a problem, but I will sonic it first. This wouldnt be an issue if I knew about it up front. No biggy...live an learn. I really like these blocks, but dealing with the little fitment issues vs. a stock block are interesting to say the least. Im kinda bummed because I already have the long block assembled when I noticed this. DOH!!!!! Everything else went smooth. Im using hydraulic roller lifters from Comp and they clear the valley unlike many other manufacturers roller lifter link bars. Crower is working on a new lifter that has a taller link bar and its supposed to be ready in a few months. Again, the block is extra beefy in the valley, which adds to the complications of fitting parts that normally fit a stock block.
Anyways, Im not complaining at all, just giving other people a heads up before assembling your engine yourself. Just a few things to look at. I know the majority of engine builders on this forum already know about this as they had to find out when these blocks came out, but for the guys that build their own engines this info could save some time and headaches.

Thanks for the heads up.

Can you share a pic showing the problem area?
As I recall, the Edelbrock RPM heads only have relatively small holes for drain back, not a big cut out in the pushrod area like some other heads.

I will post a few just for referance. I am taking this engine completely apart so as I dont get any shavings in places that I dont want. I used the head as a template to drill/mark the locations of the oil drain back holes on the block surface. The holes that my philips screw driver is pointing at were not there at all prior to me drilling. I sonic tested that area for my own knowledge and there is no issues of hitting water especially since I will drill some at an angle towards the valley and grind others that simply need minimal work to allow oil drain back.

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#5 Sorry, this picture my aim with the screwdriver as a pointer was bad, but you can easily see the dillema.

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I have a set of INDY SR aluminum heads over here as well and these heads dont have the same issue. The heads are much taller therefore the oil drainage issue is non existant. The Victor heads may be OK but Im not sure. I set the INDY SR heads on the block just to see. So I think its more of a stock style head issue here. I know it seems overkill to use this block with these heads, but my friend wanted a NEW block. 540" stock unported eddy RPM heads with a SIX PACK setup. Wierd setup if you ask me, but its what he wanted for his heavy street car. Oh yeah, its a hydraulic roller cam and the pushrod holes need to be opened up to clear 3/8 pushrods due to the tall roller lifter causing the pushrods to sit at a slightly different angle. Its all good.

The area that needed to be taken care of was solid cast iron. I drilled most of them and used my die grinder on the rest. About 5 hours later, the engine is ready to be washed and reassembled.

Many thanks for the info!

Thanks for the pictures, that shows it very well. I added some labels to your head picture for everyone.