Magnum heads on LA block

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siegenthaler.16

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have read that magnum heads flow better than j or x heads is this only the aluminum ones?

I have the heads off of my 95 dakota (computer went out) magnum Iron heads i also have a 68 long block was wondering other than push rods will the intakes bolt up or will i have to buy a special intake? I am lookin to have engine carborated?

I realse that i must have a hydrolic cam as magnum heads do not have the oil passages of the older heads.
 
you have to use the AMC type lifters that have the oil metering hole in the top.

I would use the summit racing 5/16" 7.650" length chromemoly pushrods.
You can't run a cam over .525 lift at the valve without head machining, (take rated lift, divide by 1.5 and multiply by 1.6 to get the number)

Otherwise you're looking at a set of magnum heads, magnum headbolts, magnum specific intake (air gap is the best one), magnum intake bolts and the magnum rocker gear.

This is my 77 360 with a magnum head swap
100_0799.jpg
 
I just got "How to Modify Your Magnum" by Larry Shepard. In it, besides valve spring concerns, when using a high lift cam, he stresses measuring the height of the valve guides to insure enough clearance.

From the book:

A typical Magnum has an install spring height of 1.65". Assume the keepers hit the valve guide a 1.00". This means the clearance is .650" in the closed valve position. The minimum keeper to guide clearance recommended in the book is .100", so theoretically you could install a cam up to .550" lift without concern.Of course, he recommends measuring it before installation.

Once again, this is a separate issue from valve springs.

I contacted Hughes about their Whiplash cam, which with the 1.6 Magnum rocker ratio, puts the cam at .546" int and .552" exhaust lift. They stated it shouldn't be a problem. I am concerned that it is just above what SHOULD be acceptable. I'll go out and measure, but them heads ain't coming off to get the valve guides machined!! My age and 105 ft lbs of torque don't mix well
 
I have aset sitting on my bench. If I get to it I'll check.
 
thank you for the helpfull info i hope to build me a engine with my 68 block since it has a crankshaft

what i am going to use
my 68 long block
after i put new bearings and rings in it and give the bores a nice hone job
my 95 magnum heads
my car oil pan
new oil pump and water pump
a 2 barrel intake (lack of funds prevents 4bbl)
gaskets from my rebuild kit which is where i will get bearings and oil pump
what i need
a distributer
correct lenth pushrods
the correct amc style lifters
and time to do it
and a 2 barrel carborator (since my dad can rebuild them a junkyard find will work)
motor mounts for v8 k frame I have one but no mounts
 
i should have saved my crankshaft when i sent my dakota to the scrap yard
ps does any one need a fuel pump for a 95 dakota will sell cheep
 
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