David
Any B or RB head will physically interchange. Before anyone jumps to
conclusions, the Stage series or racing heads and the B-1 and a few of the
aftermarket heads use different manifolding or different geometry, so lets
just stay within the realm of stock mass produced 361-383-400-413-440
passenger cars and avoid the race only and exotic stuff.
That said, now you get into the 3 major differences in all these heads:
1. Number of valve cover bolt holes - 4 or 6 holes.
2. Valve diameters - early engines had smaller intake and exhaust valves.
3. Open and closed combustion chambers. - Does the head have a completely
open combustion area or is it partly filled in or closed in, depending on
how one describes it
To be general,unless they have previously been swapped, the 60 would have
had the closed chamber and smaller valve diameters and 4 valve cover bolts.
I swapped an entire 440 in place of the 413 in my 62. So take the following
with a grain of salt in deciding what cylinder heads to look for.
1. The valve cover bolt holes are not an issue except for being able to
access them to replace a valve cover gasket. Its a complete pita to get at
the corner bolt holes on the heads, but not impossible. Dont let the valve
cover bolt holes be an overwhelming concern in this area, the clearance
between the valve covers themselves and the heater box, brake booster and
all that are the same , and there is always a way to get a universal swivel
socket or extension or modified wrench etc etc at the valve cover bolts.
Many mopars used studs on the valve covers, so then all you have to do is
fight with nuts and washers.
2. The valve sizes, who cares.....its not like its going to hurt the engine
to install a head with larger valves than one that had the smaller valves.
In a purely theorhetical state the larger valves breathe easier and work
better, hence the reason automakers went with them. In an Imperial with the
kind of rpms that are usually seen and if youre not doing anything with the
rest of the engine such as adding a hotter cam or going to some high
compression pistons, headers etc etc.....its probably going to be a moot
point.
3. The open or closed chambers, a 60 probably had an advertised 10.1 or
something very close compression anyway and ran on gasoline of a higher
octane than we can get now anyway. It would have had the closed chamber
head from the factory. If you swapped to an open chamber, the volume in the
combustion chamber increases a bit, and may drop the compression say, half a
point or so , down to perhaps 9.5 to 1. There is nothing wrong with that,
considering the octane ratings of the fuel you see now anyway. There are
some slight differences in how an open chamber and a closed chamber head act
when the combustion takes place, but again in the real world seat of the
pants driving, I doubt youd ever notice it in a heavy, tall geared car like
an Imperial .
Im not endorsing or knocking any particular kind of cyl head here, but if
you found a set from a 68 383 or a 72 440 or a 65 413 and they were in good
shape mechanically - no burnt or cracked valves, good valve stem seals,
everything meets specs as far as mechanical condition - any set would work
fine.
For reference, find a copy of the Mopar Performance B-RB engine book at any
Chrysler dealer or look for maybe a copy of HP Books How to Build Big Block
Mopar, or go to Allpar or the Mopar Web Ring on the web...any of these can
give you excellent reference information if you want more in depth technical
info.
Good luck, hope this helped some
Mikey
62 Crown
p.s. feel free to email me privately if you want more info
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