New EQ Head port misalignment?

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At one time I was going to try and make drilling jigs. Just what WOULD BE a "zero" reference point for everything else? I mean, the deck surface can change, so would you start with the valve spring seats? The rocker cover surface is a casting so that is not exactly a precision starting point.
 
Just measure it.

But regardless…. They’d be going back if it were my build.
oh Im certainly calling EQ again on monday. Im starting to think the deck isnt machined down all the way. But that means the valve seats are probably machined too deep, and my valvetrain wont be right... etc etc...


I don’t think the intake will even bolt on. Do you have a short block you can place the heads on and mock the intake up. No way those holes are lining up.
I bet the intake will. The bolt holes look in the right spot in relation to the deck surface, and that is what will determine the ability to bolt up. but the ports are no where close to the right spot. I guess Ill lug this out to the shop and mock it up.
 
At one time I was going to try and make drilling jigs. Just what WOULD BE a "zero" reference point for everything else? I mean, the deck surface can change, so would you start with the valve spring seats? The rocker cover surface is a casting so that is not exactly a precision starting point.
Deck surface would be my datum IMO. sure it may change a few thousandths if machined but gaskets have tolerances that a .010 skim can soak up.

And looking at the intake gaskets, they have tabs that align them up and down from the deck surface and left and right based on the headgasket. And the headgasket is doweled to the block/heads
 
I can move the gasket up 0.200" and the ceiling of the port is line-to-line with the gasket and everything looks ok (except for the obvious intake bolts. But machining the deck .200" id be well into the valve seat...
 
As a point of reference……..
On a stock 596 head, I put a straight edge against the bottom of two intake bolts and scribed a line at that point on the port center divider.
That line is 1.135 from the bottom of the head.
The bottom of the intake ports are .400 from the bottom of the head, top of ports 1.530 from bottom of head.

View attachment 1716348074
If i scribe the line you mention, from deck surface to line is about 1.100", the floor of the port is about 0.675" from the deck surface, and the ceiling of the port to deck is about 2.700" (im assuming you meant 2.530" in your post).
 
If i scribe the line you mention, from deck surface to line is about 1.100", the floor of the port is about 0.675" from the deck surface, and the ceiling of the port to deck is about 2.700" (im assuming you meant 2.530" in your post).
Oops.
Yup, 2.530”
Sounds like the ports being way off is the bigger problem.

Heads like that shouldn’t require jumping thru hoops to be able to use.
 
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Oops.
Yup, 2.530”
Sounds like the ports being way off is the bigger problem.

Heads like that shouldn’t require jumping thru hoops to be able to use.
Agreed. Im going to reach out to EQ on monday and fuss a storm and see what they say.

Anyone have a set of Magnum R/T heads they dont want?? haha

I'm 0/2 for getting projects crossed off today...:mad:
 
I think 318willrun used a set of those heads.
As I recall He had a few issues, but nothing like that.

I’m pretty sure he has a video on them.
 
I didn't know you could even get those with the LA pattern. All the newer china EQs I have worked on were magnum pattern.
 
Well, they do have the LA bolt pattern.
That seems the be where the good news ends.

Have you started thinking about a plan “B”?
 
The reason I went with these heads, is allegedly they add more material to not make them crack between the seats, played a little with the port and came with LA pattern already. I was ok with it being rough around the corners because I was already planning on some light cleanup porting anyway...

welp, not pleased with the product I received... BTW, both heads are showing the same problem.
 
I imagine they are CNC machined, so all they need to do is fix the coordinates in the bolt pattern drilling step.
 
Id say the 0.030 off is within tolerance of what intakes can absorb.

the entire port 0.200" off however.....
 
I’m guessing they located the bolt holes so the intake will bolt on……..without consideration for the port alignment.

If the bolt holes were raised .200 to be correct for the ports, the intake won’t bolt on.
 
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I suspect NC EB has probably used the Magnum style version?
Any issues youre aware of using the universal Chinese RPM intakes on those?
 
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I suspect NC EB has probably used the Magnum style version?
Any issues youre aware of using the universal Chinese RPM intakes on those?
Havnt used any of those heads in a while, last few sets were just stock replacement deals for stock magnum rebuilds, so no experience with intake fitment with the carbureted intakes.
 
I borrowed a factory magnum head from a friend and found that the floor of the port was 0.450" from the deck and the ceiling was 2.600"

So these "magnum" eq head ports are every bit of 1/8" off or more.
 
Called EQ again. Told them about measuring magnum heads and it wasn't close to that. That i also tried the magnum gaskets. I basically got a shrug of "I don't know, we sell a bunch to drag racers and factory replacement and they should be fine."

Guess I'm just going to return them and go get some factory magnum heads and drill for LA intakes.
 
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