I have seen discussion on here before, but a current search is drawing a blank...
which of the various heads available on the /6 over the years, is best "bang for buck"?
of what I have here on hand;
peanut head w/o the provision for the AIR pump? I have 2.... 3698447 bare here, and fully assembled (but could use a goin 'thru) 4027600
drool tube head? I have here a 2843168.
I also have the original head on my '85 truck slant engine (valve cover yet to be removed to get casting number)
yeah I know about the being able to (or not) pull the lifters out w/o removing head, issue... not concerned about that right now.
gathering parts, thinking ahead to a possible engine build up for a 1/2 ton long bed D150...used as the truck that it is....
any of these heads take better to mild port cleanup (mostly thinking casting flash/fuzz removal)
any better to swallow some oversize valves?
any better to accept a shave (or most likely to "need" one, to bump CR??)
would the drool tube head I have, have hardened seats already?
just acquired most of a "BH" forged crank engine, thinking of a buildup with that, as my base.

Wider selection of spark plugs for the plug-tube (pre-'74) heads, so I'd vote for a '67-'74 head such as your 2843168 without air injection provisions (which make the head heavier).

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Too many people who were born on third base actually believe they've hit a triple.

leaded gas was normal back then... no worry about valve seats in the older head?

This is »checks calendar« 2020. If you're building a head—any slant-6 head—you put hard seats in if you're a smarty. The factory '72+ induction hardening was very shallow, only about 0.40" deep if all went perfectly, and would surely go away in the course of a normal valve grind.

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Too many people who were born on third base actually believe they've hit a triple.

I use the late hydro heads (81 or so and up, can still get lifters out w/o removing head, same wt as early drool tube heads) or something in the 64-74 range. I have put hardened seats in several heads, which has worked fine. I have also done heads w/o and they have been fine, IF using stainless valves. Stock valves on stock reground seats w/no lead I have seen fast wear/recession.

The late 70s heads may have the most meat for porting, but they are 7-10 lbs heavier than later or earlier years. Some folks think the chamber redesign in 1968 makes a difference. I have not found convincing evidence of this, but would probably pick 68-74 if I had a bunch of heads staring at me and could choose easily. The fastest drag racers have used heads of all kinds.

No one has done any kind of systematic MPG or emissions test comparing heads, that I know. Perhaps the factory did when they switched to the 68-up chamber design??

Lou

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Home of Slant6-powered fun machines since 1988

Decades ago I took a couple of heads to a guy in Newport News Va. to check out. He was nicknamed "Head Boy". He was in a wheelchair and was rumored to have worked for a big racer from the day at one time. He had a drag car with hand controls, can't remember what it was. He had a flowbench in a small shed in his back yard full of BBC, SBC and Ford heads. He was excited to see a slant head, something different to work on. I took a big valve drool tube and a peanut plug head. He really liked the chamber shape of the peanut head. The big valve drool tube, not so much. It rained to no end that night, we joked about having to build an ark to get out of the back yard! I can't remember if I was with Will or Bob.

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Hyper_pak

if the biggest disadvantage to a peanut plug head is a few extra pounds, no worry.... the build I have forming in my head would be going into a 1/2 ton truck being beefed up to be "used as a truck is typically used".... 10 lb won't mean much... would that extra weight be worth anything as a "heat sink" to help the cooling system wick heat away???? (just a "dumb Q", as I hear the TV behind me incessantly talking about Coronavirus.... ) or would it retain more heat, making a popped head gasket more likely, on a souped up motor? I would think the extra mass would be less likely to warp.

have a couple of different ways I could go with this, in mind..... one would be just a major shave to up the CR and a mild "RV-type" cam, (I have a cam that would be a good core to send off for regrind) the other idea I'm toying with would involve a blow thru turbo with up to ~10# of boost assistance for the squeeze.....
I have a "BH" block and forged crank (think it is 1974 block, numbers on head flange not all stamped well enough, to be easy to decipher) to base this build onto.... plan is to slowly acquire parts, as I run it with the stock original engine as long as it may be willing..... the drool tube head I have is the original head from this block.

I think the drool tube heads have better spark plug selections available...

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes