I just pick up set of factory magnum heads off a 318. Right out of the machine shop . Without resorting to a roller cam, what do I need to bolt to a LA motor? Alt/WTR PMP/PS all the same? Running an electric fuel pump so no need for the mech. pump eccentric. Magnum intake only? Magnum rocker only?.THX
MAGNUM HEADS ON LA
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pishta
I know I'm right....
Magnum rockers are pedestal so no LA shaft mounts...the head bolts bolt right up, use a Crosswind or Chicom dial pattern intake. You'll find the Magnum heads flow better than any stock LA head. You can even use LA valve covers on Magnums just use 5 of the 10 holes! Not 100% sure of the accessory holes for alternators or pumps off end of Magnum head.
Professor Fate
Push the button, Max...
LAs oil the valvetrain through the block, Magnums oil through the lifter/pushrod; so "without resorting to a roller cam"- you'll need oil-through flat tappet lifters (either hydraulic or solid) and custom-length hollow oil-through pushrods.
When selecting the LA cam, remember that they're spec'ed at the LA's 1.5:1 rocker ratio, and Magnums use a 1.6:1 rocker. Adjust the numbers accordingly.
Take into consideration the Magnum's 62cc combustion chamber as opposed to whatever head it's replacing on your unknown LA (you never did say what it was, just "an LA").
You'll need either a Magnum specific intake, or have the Magnum heads redrilled with the LA bolt angle.
And just so you know, LA water pumps (Auminum right side inlet or iron left side inlet) do NOT fit Magnum timing covers, just as Magnum pumps do not fit LA timing covers.
When selecting the LA cam, remember that they're spec'ed at the LA's 1.5:1 rocker ratio, and Magnums use a 1.6:1 rocker. Adjust the numbers accordingly.
Take into consideration the Magnum's 62cc combustion chamber as opposed to whatever head it's replacing on your unknown LA (you never did say what it was, just "an LA").
You'll need either a Magnum specific intake, or have the Magnum heads redrilled with the LA bolt angle.
As long as they match whichever timing cover you're using, accessories still fit. The heads have no bearing on accessory fitment, everything bolts to the block/wp/tc - the one bolt boss on the head that you'll need is also present on the Magnum head.
And just so you know, LA water pumps (Auminum right side inlet or iron left side inlet) do NOT fit Magnum timing covers, just as Magnum pumps do not fit LA timing covers.
dirty white boy
50 yr old Juvenal delinquent
and you need magnum head bolts as there different than LA's
Kendog 170
Let the boy go !
Will need the magnum head gaskets won't he? Along with AMC oil thru lifters.
Personally I would drill the head for the LA intakes.
And don't go with a wild cam with those stock Magnum valve springs.
Personally I would drill the head for the LA intakes.
And don't go with a wild cam with those stock Magnum valve springs.
LA head gaskets can be used.
dirty white boy
50 yr old Juvenal delinquent
any head needs valve springs that match the cam used...DWB
pishta
I know I'm right....
I swore I wrote about the oiler pushrods and lifters in my post, I think I deleted an entire sentence somehow before I posted. Magnum heads are very good compared to LA stockers. Keep chasing those X heads while you get passed by the same combo with $70 Magnum heads.
All replacement SB lifters I've ever bought have had the hole for pushrod oiling, nothing special there anymore.
They list the same exact lifters (hyd flat tappet style anyway) for AMC as for SB Mopar, and I believe that hyd /6 and big blocks also call for the exact same lifters.
They list the same exact lifters (hyd flat tappet style anyway) for AMC as for SB Mopar, and I believe that hyd /6 and big blocks also call for the exact same lifters.
I've done the magnum head > LA bottom end swap a couple of times. Both times with EQ heads.
With a small (what used to be called) "RV" cam, really woke up the engine beyond what a similar build with the same cam and stock LA heads did
With a small (what used to be called) "RV" cam, really woke up the engine beyond what a similar build with the same cam and stock LA heads did
A little better ports, a little larger valves. smaller valve stems, and a closed chamber make them what they are. You would have to work on a LA head to make it equal. (like a #920 or a #302)
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