Will a 75-up peanut plug head seal properly on a 60-62 aluminum block? Specifcally, will the later head seal the water jacket from the lifter gallery on the aluminum block or is the shape of the wall separating the two on the aluminum block sufficiently different such that the 75-up head will not seal the aluminum block?

Inquiring minds want to know!

I would think with the correct head gasket, the head would work.

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Hyper_pak

That is my thought as well, but I am in a discussion with someone who insists that the shape of the lifter gallery wall on the aluminum blocks is sufficiently different to the point that the 75-up head won't seal. I have never seen or heard of any difference that precludes using any slant head on any slant block.

the 75 up head is a closed deck compared to the 74 down head.
yes they are different shapes but the 75 up has more sealing area not less.

so my $0.02 = yes it will work you win the esoteric battle reed!


Greg

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http://www.youtube.com/hyperpack

Excellent. This is what I thought.

According to Doc and SSD:

"All of the aluminum 225s have “casted-in” iron bore liners and came with iron cylinder heads. Initially the heads had the word "SPECIAL" cast in where the casting number was usually placed (above number 5 intake/exhaust runners outside the valve cover rail). Later, a five-pointed star was used to denote the special head for use with the aluminum block, which had slightly smaller combustion chambers and tighter control of combustion Aluminum Block Sealing Surfacechamber placement to assure proper head gasket sealing. This was necessary due to the relatively narrow area available at the top of each cylinder liner for gasket sealing. For the 1963 model year, the tighter placement control and smaller chamber diameter were communized on all Slant-6 heads; any '63 or later cylinder head can be used on an aluminum 225"

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If it was easy, everybody would be doing it.

I read that article and based my belief on it. I trust Doc and Dan far more than myself on these sorts of issues.

Me too. They've gotten me out of a lot of jams.

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If it was easy, everybody would be doing it.

Some images,
Alum block #6 with old correct gasket, Alum block w/steel shim, Alum block.

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Hyper_pak

Thanks hyper_pak!

Yes I think we have the answer. You can use later heads on alum blocks with the right gasket. You can use a 75 up head on any slant (ex hydraulic) so it stands to reason it could also be used on a aluminum slant.

One day I am going to see how much weight I can get out of the 75 up head. I want to be able to get to the lifters without taking the head off. Still like the drool tubes, but better plug selection, better chamber shape, and less chance to leak oil. But that head is HEAVY.

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Hyper_pak

Ex (I assume you mean "except") hydraulic…? Why?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

It is interesting you mention weight. I believe my 1984 Dodge FSM for a Dodge van states the hydraulic motor actually weighs less than the mechanical lifter motor. I need to dig that tidbit out. I know for a fact that the stock timing set on an 84 slant is about 1/2-1/3 the weight of an early 60s slant stock timing set.

As far as the head sealing goes, I can't see why the 75-up head would not seal the aluminum slant. Then again, I have never even seen an aluminum slant in person.

The 75-80 (or 79?) solid lifter head will fit with no trouble. The 81-up hydro head has scalloped out water jacket holes and may not have sufficient surface to seal to the open deck Al block.

The ~ 83-up hydro motors weigh 35-40 lbs less than the mid-late 60s forged/solid lifter motors. I have weighed many many heads and blocks from early-ish 60s to mid 80s. 70s cast crankers are the heaviest. Feel free to ask q's.

Lou

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Home of Slant6-powered fun machines since 1988

Al block question....can an al 225 block be cut down to make a 170 block? If it would work, that might be a way to use an al block with bad corrosion around the top of the cylinders. I don't have one, just thinking.

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Dave

1977 d-200 crew cab ex-army pickup wants it's /6 back
1962 Valiant 2 door, 170, three on the tree
1972 d-100 parts truck
80 volare wagon now a parts car