Lou .... The Eddy heads sure are great HP heads .. but for something
like we have here? ...I don't think so !! ... You mention
that "hill" .... I have not seen that but I have heard of it.
Big "hill" - correct ?? ... I will bet that a set of HP alum heads
would not make ONE full-pull in a 10,000 lb motorhome !!!

From what little "R&D" I have done ... those 943 heads are PERFECT
for all-of-us! And I am going to do more R&D. They are going to go to
a guy with a flow bench to try and make them swirl-ports. The cost of
a standard set of 943 heads? .. if you play your cards right - some
people throw-them-OUT ! The last Mopar Nats I was at .. there were
TWO sets sitting by the junk-barrel on Sud=ndat late afternoon.


The blocks? ...were a special casting done by Chrysler only for the
truck/motorhome chassis. They had the MH and truck market COVERED
back in the late 60's/early 70's and they wanted to keep it that way
and made the decision to make a bullet-proof motor. The 413. The
reason WHY they went to a 440 in 1974 ? .... the gas-crunch and the
cost. I was told the cost-diff was over 200$ per unit !! ... Special
block casting, those massive heads, special exh mans and water pump.

Opppps ...I will BBL. My "other" wants to go into town. ... Eric




--- In FMCMotorCoach@yahoogroups.com, "Louis Cruse" <xjetmec@...>
wrote:
>
> Eric, I think Edelbrocks and others aluminum heads have pressed in
> valve seats. They were really made for drag racing and or fun on
the
> street Saturday night. Aluminum expands thermally more than cast
> iron. Pressed seats fall out and aluminum heads often crack between
> exhaust seat a spark plug holes, as do cast iron heads but only
> occasionally. Aluminum cools better than cast iron, but the HT413
has
> a completely different cooling system than the 440 heads in
aluminum
> or cast iron. The RollsRoyce Merlins, Allisons, R-2800s, 3350s, and
> 4360s that I worked on in another life all had screw in hard seats.
> The HT413 has screwed in exhaust seats. I CAN GET CAST IRON HT413
> HEADS CHEAPER THAN ALUMINUM 440 HEADS. Silk purses and sows
> ears . . . its a 35 year old Motorhome, not a Bugatti, or Delahey,
or
> Dusenberg. How many aluminum headed pressed seated 14,000 lb trucks
> have you driven up the hill between Indio and Chiracio Summit CA,
> when ambient was 118º ?
>
> I have never seen any data detailing the difference in the HT413
> block and a 440 block. If it has thicker walls then it is heavier.
I
> don't think firing pressure and or dynamics of the crank in the
block
> is an issue on either engine. They may have the same steel crank,
and
> main and rod journal diameters. My 440 engine has less than 3000
> miles on a complete rebuild verified by the sales receipt, which I
> believe, from the guy I bought it from. I'm attempting to make a
> cooler running engine not a "stouter" one.
>
> I have read where newer (at the time) thin wall casting methods
> allowed the 440 to be made. Iron was sold by the pound then and
still
> is. A thinner walled block might even cool better. All mechanical
> systems are a compromise. What do you want to die from ? Heat
> transfer coefficient ? Young's Modulus ? Third harmonic ?
Inteference
> fit calculation ? Bank balance ? I've made my choices. What have
you
> built or modified in you FMC 440 ? Sure would like to see a picture
> of seven HT413s all together. What are you going to do with them ?
> Would love to have a HT413/HT361 Service and Overhaul book. Have
you
> ever seen one ? Have fun, Lou #120.
>
> --- In FMCMotorCoach@yahoogroups.com, "Eric " <niteowl440@> wrote:
> >
> > Wow Lou ... it sounds like you are well into the project. Just
> where
> > are you exactly in the completeing it ? .. Your alum head
> > consideration ?.... and saying they might "move around" ?? ... I
> > think that those would give MOVING AROUND new meaning on high-
load
> > motorhome application !!
> >
> > Something though you did overlook. The 413 block is a much better
> > piece than a 440. The later 413 was built for HD use...and has
> > thicker cyl walls and beefier bottom-end. The 440 block is
nothing
> > more than a passenger car piece with premium parts.
> >
> > Eric
> >
>