Author Topic: magnum heads  (Read 914 times)

Offline 1970-cuda340

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magnum heads
« on: July 13, 2008 - 10:23:21 PM »
I have a 1968 340 block and a 1992 magnum 318. What exactly do I need to get or do to get the heads useable on the 340?  :dunno: I see the magnum heads has pushrods with oil passages.
Thanks!!!    :working:




Offline mikerallye

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Re: magnum heads
« Reply #1 on: July 13, 2008 - 10:51:33 PM »
There is a book titled "How to Build Big Inch Small blocks" that  goes into great detail on this swap. I recall that the mag heads will use sbc rockers and must have the mag intake or drill out the LA intake to fit the heads. I have seen this swap discussed here as well. Search this site, it should be here.  :cheers:

Offline matt63

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Re: magnum heads
« Reply #2 on: July 13, 2008 - 10:57:59 PM »
i"ve got Eddy Magnum heads on my 360LA block.  I just swapped pushrods for the oil thru type.  If you're swapping cam bearings you can block off the oil holes to the old rocker shafts but I didn't.  You will also need the Chevy small block stud mount rocker arms and of course Magnum intake and valve covers.  The Magnum intake has a different bolting arrangement than the older LA style and has 10 bolt valve covers instead of 6 IIRC.  You will need to learn how to properly tighten the Chevy style rocker arm nuts so they don't come loose on you.  If I had to do it again I would just stick with the older LA stuff.  I think I went with the Eddy Magnum heads because of the combustion chamber size and the great selection of inexpensive Chebby rocker arms.

Matt in Edmonton

'68 Valiant
'73 Cuda 340 4 speed (408) SOLD

Offline Chryco Psycho

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Re: magnum heads
« Reply #3 on: July 13, 2008 - 11:05:17 PM »
this why I usually use 308 castings

Challenger - You`ll wish You Hadn`t

Offline 1970-cuda340

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Re: magnum heads
« Reply #4 on: July 14, 2008 - 09:49:29 PM »
Doing a swap is a little more than i bargained. I think I will rebuild these j heads I have. Don't like the idea of chebby parts on my mopar anyhow :grinno:

360-308 heads are a little hard to come by around here.

I do have a 1980 318 truck engine with factory 4bbl option complete in a 250 RAM. Think of anything I can use off that?

Offline Chryco Psycho

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Re: magnum heads
« Reply #5 on: July 15, 2008 - 02:07:12 PM »
1980 318 engines didn`t have much to offer

Challenger - You`ll wish You Hadn`t