New EQ Head port misalignment?

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I used a set of these with the magnum intake pattern.
I also used a Chinese magnum intake. The intake ports were a bit smaller than the cylinder head but nothing ridiculous.
 
For reference, here are some magnum heads with gasket on them
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What a mess.
Can you post a picture of the chamber valve seat area? I'm curious if these heads are the same ones that are being used by a lot of other people as their replacement head. I had to remove a lot of floor out of some others and they might be the same head. I used Edelbrock Magnum gaskets.
 
In relation to the ports, agreed. Or ports are cast into the wrong spot. But potato potato.

But the bolt holes seem to be at the approximately the right height off the deck surface.
Geez, dude. Do you think you're going to argue the bolt holes into the right place? Send um back already.
 
What a mess.
Can you post a picture of the chamber valve seat area? I'm curious if these heads are the same ones that are being used by a lot of other people as their replacement head. I had to remove a lot of floor out of some others and they might be the same head. I used Edelbrock Magnum gaskets.
This is the only picture I took of the valve seat area before I sent them back.

huge lip left in the bowl and a decent ridge in the chamber too.

Also note the casting scab they tried to clean up in the chamber.
IMG_20250106_212251.jpg
 
Already threw them back at FedEx. Just thought I'd document the caparison for any future viewers of this thread.
Good deal. I HOPE you get it taken care of. What are your plans? Get a refund and try another source for heads or let them send you more? That link you posted seemed to show the heads exactly as yours are, with the holes drilled in the wrong place.
 
This is the only picture I took of the valve seat area before I sent them back.

huge lip left in the bowl and a decent ridge in the chamber too.

Also note the casting scab they tried to clean up in the chamber.
View attachment 1716350666
As if they're 2nds.

Most of these cheapo mags are messy and require work, a lot. Speed crapper mags in the picture. Port windows very rough in shape and common wall misalignment.

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Good deal. I HOPE you get it taken care of. What are your plans? Get a refund and try another source for heads or let them send you more? That link you posted seemed to show the heads exactly as yours are, with the holes drilled in the wrong place.
I'm just getting full refunds and going to find some stock magnum heads and drill them myself for LA intake. Bout to head out to the junkyard for some. Only problem is it just snowed like 4 inches last night....
 
Bout to head out to the junkyard for some.

Good luck in your search!!

The main reason stock replacement Magnum heads are so readily available is……..factory ones are usually cracked.

Currently you can buy replacement Magnum bare heads for $482/pr with free shipping on ebag.
I don’t know how that compares with what you spent for the EQ’s…….and not that this means anything, but the ports don’t look as high on them in the pics as the EQ’s.
 
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Good luck in your search!!

The main reason stock replacement Magnum heads are so readily available is……..factory ones are usually cracked.

Currently you can buy replacement Magnum bare heads for $482/pr with free shipping on ebag.
I don’t know how that compares with what you spent for the EQ’s…….and not that this means anything, but the ports don’t look as high on them in the pics as the EQ’s.
Fundamentally, the eq heads are the same as magnum replacement heads. They just drill the intake different. And the intake bolts seemed in the right spot.

Got a set of heads this morning. One side seems good, the other has one cyl with a crack. I'll probably just run with it but I'll keep looking the heads over.
 
Fundamentally, the eq heads are the same as magnum replacement heads. They just drill the intake different. And the intake bolts seemed in the right spot.

I thought you measured the port locations and saw the bottom of the EQ port was like .200” higher than the stock head(.675” vs .450”).
 
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I thought you measured the port locations and saw the bottom of the EQ port was like .200” higher than the stock head(.675” vs .450”).
Correct. This was measured from the deck surface. Measuring the deck to the bolt holes, it seems to be in about the right spot.

Just because the ports are off doesn't mean the bolt holes are. I am betting the bolt holes are referenced off the deck, not the ports.
 
Also, follow up on the new magnums, turns out 5/8 of the cylinders are cracked. Oh well.
 
During the late 90s I read in a magazine article that pretty much all Magnum heads crack between the seats but is a nonissue for a driver or even street engine.
 
Hoping someone has seen something like this before and can point me in the right direction....

Bought some EQ heads (CH318B) with the LA intake pattern to put on my 408 build. everything it a bit rough around the edges but I kind of expected this and dont mind a little porting to clean them up.

Problem comes in when I was overlaying the intake gaskets to get an idea of what work I need to do. The intake runners significantly off!! The bolt holes seem to be in the right spot... where the gasket would rest on the china walls seems to line up with bolt holes... even the water ports dont look like theyre correct.. (not shown)

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However, the gasket lines up just fine with the intake (7576 RPM air gap). If I bolt the two together, you can see the intake has a significant mismatch, similar to the gasket but not as extreme id say.... (not shown)

View attachment 1716348035

I called up EQ, and they said Id have to run the magnum style gaskets as the port is raised and likely some porting. However, that wouldn't solve the intake mismatch....

Has anyone seen this before? Is this a common thing if running magnum style heads? Or did I get some junky EQ heads?

Id prefer not porting the intake specifically for these magnum heads.... but im ok with modifying the heads to work with LA intakes..
Crap. I bought the same heads from a reputable shop a year and a half ago. I had them immediately checked out. The seats and guides were spot on. I then had the shop machine the guides for a higher lift cam. I have started porting them as well. Prompted by this topic I fit a Magnum intake gasket to mine and have the same results as the poster here. This sucks. I planned to run either a Weiand TR or an Offenhauser dual quad intake so having a Magnum head with the LA intake bolt arrangement is crucial.

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I'm just getting full refunds and going to find some stock magnum heads and drill them myself for LA intake. Bout to head out to the junkyard for some. Only problem is it just snowed like 4 inches last night....
Man, I wish you great luck in finding an uncracked pair!
 
During the late 90s I read in a magazine article that pretty much all Magnum heads crack between the seats but is a nonissue for a driver or even street engine.
"Sometimes". If they crack deep enough, you're screwed with a capital F.
 
Crap. I bought the same heads from a reputable shop a year and a half ago. I had them immediately checked out. The seats and guides were spot on. I then had the shop machine the guides for a higher lift cam. I have started porting them as well. Prompted by this topic I fit a Magnum intake gasket to mine and have the same results as the poster here. This sucks. I planned to run either a Weiand TR or an Offenhauser dual quad intake so having a Magnum head with the LA intake bolt arrangement is crucial.

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Can you just open up the intake bolts holes? Or use an LA gasket?
 
Crap. I bought the same heads from a reputable shop a year and a half ago. I had them immediately checked out. The seats and guides were spot on. I then had the shop machine the guides for a higher lift cam. I have started porting them as well. Prompted by this topic I fit a Magnum intake gasket to mine and have the same results as the poster here. This sucks. I planned to run either a Weiand TR or an Offenhauser dual quad intake so having a Magnum head with the LA intake bolt arrangement is crucial.

View attachment 1716351698

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Mock this thing up on your block and see if the intake lines up with the ports. From the placement of your gasket in the last picture it appears the intake will line up correctly with the ports. If so, you can probably fix this by plugging the original holes with bolts, cut them off flush, then re-drill new holes in the correct location. it looks like they will overlap the original holes a little, locking in the cut off bolts. like old school pinning technique. That should save the work you have into them already.
 
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"Sometimes". If they crack deep enough, you're screwed with a capital F.
I think im going to have them pressure checked. If they pass, im just 'gunna send it.

Crap. I bought the same heads from a reputable shop a year and a half ago. I had them immediately checked out. The seats and guides were spot on. I then had the shop machine the guides for a higher lift cam. I have started porting them as well. Prompted by this topic I fit a Magnum intake gasket to mine and have the same results as the poster here. This sucks. I planned to run either a Weiand TR or an Offenhauser dual quad intake so having a Magnum head with the LA intake bolt arrangement is crucial.

View attachment 1716351698

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I would double check with measurements before you completely assume. Measure the top, bottom, and bolts with reference to the deck surface.
 
Mock this thing up on you block and see if the intake lines up with the ports. From the placement of your gasket in the last picture it appears the intake will line up correctly with the ports. If so, you can probably fix this by plugging the original holes with bolts, cut them off flush, then re-drill new holes in the correct location. it looks like they will overlap the original holes a little, locking in the cut off bolts. like old school pinning technique. That should save the work you have into them already.
This is what I did, with the heads off the car, and no valves in the heads, I bolted the intake on with and without the gasket and could see the drastic misalignment.

So even if one modifies the bolt holes in the gasket (as EQ suggested), that wont help any intake misalignment.
 
This is what I did, with the heads off the car, and no valves in the heads, I bolted the intake on with and without the gasket and could see the drastic misalignment.

So even if one modifies the bolt holes in the gasket (as EQ suggested), that wont help any intake misalignment.
But you used the bolt holes in the heads, right?
If both heads are placed on a block, then the intake is placed on the heads with no bolts, we can see where the intake will "sit" on the heads and if the ports line up with intake. Again, ignoring the bolt holes. if everything lines up pretty close, just drill new holes.
 
I think im going to have them pressure checked. If they pass, im just 'gunna send it.
I would endorse that. Even if they show cracks on the surface. You'll just have to hope they crack farther. That's the thing about cast iron. You just never know. I hope you find some uncracked ones, though. They're out there. You might even try Allied Cylinder Head. They have reman Magnum heads for 632 including the gasket set. But you need to call them and verify they have the 5.9 heads. They seem to lump the 5.2 and 5.9 heads together on their site, and that's incorrect.
 
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