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good price, but you'll need to change springs out of stock mag heads if you plan on running anything bigger than a stock 360 or small summit cam....

also, just because they came off of a running engine doesn't mean they aren't cracked....

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I have all the stuff here I am about to do the Magnum head swap on my 83 D 250 with a 318;
if AT ALL possible I REFUSE to buy China made $#!T
Here's what I did, and it will allow you to run ANY LA intake, so you don't need the special Magnum intake throttle brackets, etc. I had my magnum heads redrilled to the LA intake pattern; same hole location different angle. There are some of them where the threads are thin on 1 side of the hole but using magnum gaskets and the Magnum spec of 12 ft lb instead of the LA 45 ft lb (I think the threads will "pull out" before I get there, and that gargantuan torque is mot needed on an alum intake even on a completely-LA engine.)
I think if I were to do anything different, (I may return the heads for this mod before I swap them in) I would go a lil BIGGER so I could install a Thread insert (Heli coil, etc) in the heads. (Hughes may include this in their job I am not sure) I am using the stock LA spec 3/8-16 intake bolts instead of the Magnum 5/16-18.

Set an LA intake gasket on top of a Magnum head, center-up the ports and you will see the bolt holes are in the same place. I sent an LA intake gasket with the heads to the machine shop so they had a "guide".

I have never seen a set done by Hughes but they modify heads this way quite often for $80. Cheap.
I had mine done by a local job-shop (non automotive) machine shop for a lil less.
But add that to a readily available LA intake (there were a few even at the "all-Chevy" swap I went to yesterday) 2 seperate sellers had LA engine Performers for $50 and $75. The $50 one was grungey the $75 one had been nicely cleaned up.

But this would definitely be a better budget way of having your Magnum heads (cake) and better choice of intake, for a more reasonable price (eating cake too)

I am using the thinner 0.028" head gasket from Mopar Perf and I have their push rods here too; from the stories I hear about pushrods I hope that does not bite me. Everything I hear, says that you need pushrods 0.025" longer than MP's conversion ones. The "normal head gasket is 0.042", so I am hoping that the difference between the thin ones and the thick ones, make up the difference in the push rods working or not. My Magnum heads wound up not needing a "clean up" milling.

On pushrods I have also read that Summit and others, have the 7.650" ones they are a standard pushrod for some engine I am not sure what. (use the "buyer's guide" section where they list each P/N pushrod by length diameter end-type, etc.in the back of the book. IIRC, that length pushrod is a standard length for some Ford motor.

My wife is taking a week off work next week so I will have my "window" to do the head swap, and have a vehicle here to drive during the swap.

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There are some of them where the threads are thin on 1 side of the hole but using magnum gaskets and the Magnum spec of 12 ft lb instead of the LA 45 ft lb (I think the threads will "pull out" before I get there, and that gargantuan torque is mot needed on an alum intake even on a completely-LA engine.)

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There are some of them where the threads are thin on 1 side of the hole but using magnum gaskets and the Magnum spec of 12 ft lb instead of the LA 45 ft lb (I think the threads will "pull out" before I get there, and that gargantuan torque is mot needed on an alum intake even on a completely-LA engine.)

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I would bet $$$ that you are going to end up with an intake leak only running 12 ft.lbs of torque instead of the 45 ft.lbs you are supposed to with an LA intake. Maybe not right after install, but eventually and the difference in the coeffecient of expansion between the aluminum intake and the cast iron heads will make it happen even quicker.

The different angles at which the threads go into the head is the reason for the different torque specs, when you are tightening sraight down with the Magnum pattern you are actually pushing the intake surface against the head surface, when you go in at an angle like the LA pattern you are pulling (stretching) the intake to the head thus the higher torque requirement.

Trust me, I'm a engines engineer, i.e. I design engines for a living. I can guarentee you are going to have problems with this set-up.

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I would bet $$$ that you are going to end up with an intake leak only running 12 ft.lbs of torque instead of the 45 ft.lbs you are supposed to with an LA intake. Maybe not right after install, but eventually and the difference in the coeffecient of expansion between the aluminum intake and the cast iron heads will make it happen even quicker.

The different angles at which the threads go into the head is the reason for the different torque specs, when you are tightening sraight down with the Magnum pattern you are actually pushing the intake surface against the head surface, when you go in at an angle like the LA pattern you are pulling (stretching) the intake to the head thus the higher torque requirement.

Trust me, I'm a engines engineer, i.e. I design engines for a living. I can guarentee you are going to have problems with this set-up.

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I never liked the 45ft lb spec of the factory LA anyway; I have had the threads pull out at that reading, on dead stock all-LA engines trying to get there. (my mom's '84 5th avenue and dad's 86 B-van come to mind) I've done 35 ft lbs since then on these, with no problems with all cast iron components.and I always anti seize the bolts. IIRC the last couple LA aluminum intakes I have had I have gone ~20-25 w/o a problem. but I don't use the 318-2 barrel shim steel type intake gaskets either.
Alot of the reason for 12 ft lbs is the smaller bolts on the Magnums.
and they liked to snap off upon removal with that small number.

For the guy that had the jig; Did you have any issues with on;y having 2-2/2 full threads on one side of a couple of the new bolt holes? Did you drill and tap for the magnum spec 5/16, or the LA spec 3/8 bolts?

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I have re drilled and taped a ton of these useing the LA intake bolts and 25ft lbs tq and have not had one of them come back yet. It was about 5 years ago I first did one and he drives it a lot but he does have a cast iron factory intake, all the others are aluminum intakes and not leaking either.

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I have re drilled and taped a ton of these useing the LA intake bolts and 25ft lbs tq and have not had one of them come back yet. It was about 5 years ago I first did one and he drives it a lot but he does have a cast iron factory intake, all the others are aluminum intakes and not leaking either.

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I've replaced several LA intakes without using a torque wrench and simply going as tight as I can with a short ratchet and haven't had a problem yet, so I can believe that 25 ft.lbs would be enough, but 12 ft.lbs sounds a bit low to me.

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so should i just go with the magnum intake?im guessing thats best.it even kinda makes sense!

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The intake bolts on an LA are not exactly perpendicular. I made my own jig and used an LA head for the pattern not the intake or gasket. I bolted the two pices to an LA head intake face and clamped them to the chamber side with welding clamps and welded it together.

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CRAP!!! I took my heads to a local job shop (non automotive machine shop ) and gave them a set of LA and a set of Mag intake gaskets to go off of; I just tried a mock up of my Performer intake onto those heads atop a 38 Mag block I have on the stand, and some LA FelPro head gaskets I had layin' around, and yup; the bottoms of the bolt heads hit before the tops (closest to the valve cover) do; I guess I take em back and have em re redrilled at the correct angle and Heli Coils installed; they are close enuf that the enlarged holes the Heli Coils require will be able to alter the angle correctly, for an LA intake. I guess that's what I get for [Edited by Moparts - Keep it clean]-u-ming, huh?