Hey Patrick i have to believe they are below the deck, they are like i said stock for 73

"Should" be. Did you buy it from someone,do you trust that person? Nobody but you can tell at this point what you have.

If it's a stock '73 motor, than yep, they should be below deck. if it were mine then, I'd probably run mag heads and the thin MP or Mr. gasket head gasket (like .028" thick).

there are 2 casting numbers for factory magnum heads, going by memory, I think they end in '671 and '466, but don't quote me on that. IIRC the '466 ones are about 10cc bigger in the intake port, but according to Jesse Lackman, he hasn't seen any significant flow difference between the 2 castings.

the major PITA with mag heads is finding a suitable spring/retainer combo without a lot of monkeying around or spending a lot of coin. the MP springs/retainers end up being ~$17/valve (x16 valves), so they get real spendy real quick. if you have a moderate lift cam, gm 3100 springs/retainers may work for you. read the "best of" post for specifics on that. annecdotally, I know hotroddave has had those springs work w/o coil bind on cams up to .5" lift, when I measured them on the heads under my bench, I'd be a little nervous with lift over .480" and someone else on the board had them coil bind on their particular heads at like .465" lift. you need to measure for sure.

chrylser 2.2L/2.5L retainers are essentially the same as the MP ones, and allow the use of any 1.4"ish diameter spring, so that opens up other possibilities.

mag heads are somewhat crack prone between the seats, so YMMV with used heads. annecdotally again, it seems like your odds are better finding non cracked heads on a 318 vs. 360. it may have something to do with the EFI mapping for timing & fueling.

if you wanted to avoid all the hassle, I'd buy a set of Enginequest 318B heads. they're beefed up/improved mag replacement heads cast in new zeeland, the A's have a mag intake bolt pattern, the B's have an LA pattern. Hughes sells them as "iron ram" heads (see their website for details).

I contacted a enginequest dealer a while back, Carolina Machine Engines (http://cmengines.com/) and they quoted me a price of $650/pr + ship for new 318B's assembled with new OEM replacement valves, & GM 3100 springs set up at 1.65 IH,
and $850/pr set up with small block chev 11/32" stem valves .1" longer than stock, and springs good for .55" lift with a hydraulic roller cam.

as far as recommending a cam choice, tell us how far down in the hole your pistons are, and what kind of powerband he's looking for (idle-5000? 2000-5500? 2500-6000 RPM) and we can help pick a good cam. if the pistons are down in the holes a way, compression with the mag heads might be ~9:1, and with that, I'd probably look for a cam with 212-218@.050 duration on the intake lobe.

Just one person's opinion,
but I feel the stock Magnum combustion chamber is optimum for the 318 V8,
and that when Chrysler used the 'soapdish' piston on the 5.9L/360ci with that same 318 sized combustion chamber
it should be considered a cost cutting move
that does not provide best performance.

If the flat top pistons were 'optimum' for the Magnum 5.2 V8,
why not flat tops for the 5.9V8 too ?

A new cylinder head casting (and its cost)
should have been made by Chrysler engineering for the Magnum 5.9 V8
with a larger CC exhaust side cavity...
like what Larry Widmer recommends
for fast burn swirl heads resistant to detonation.

Sonic test your Magnum head combustion chamber walls
and remove as much CC from the exhaust side as is safe.

Consider sodium filled exhaust valves as well.

It is also a shame
that the V10 style intake manifold design
was not made for the 5.2/5.9 Magnum V8s
after 1995 or so
this would have eliminated the plenum gasket failure fiasco,
and improved 1000 to 2500 rpm torque

Dave that is good to hear.I am going to mill/deck to get .035 quench with my badger .020(flattop) pistons & that is going to put me definitely way up into the 10's. 360 w stock cam & stock(new)magnum heads. For a low rpm daily driver that must run on 87 octane. PATRICK I am glad that you are indeed among the living & that reports of your recent demise were somewhat exaggerated.