FWIW, I just pulled the CI head off my '66 because I
thought a leaky gasket may be to blame for some
heating I was getting. WRONG! No leaking after 107k
miles without the head ever having been off. What's
more, I took it to a good machine shop, had a bolt
extracted from the thermo housing (happened a long
time ago, I've lived with 2) and asked him to polish
or resurface it if needed at all. He said it needs
nothing. perfectly straight, and leave it alone.
Pretty cool for an oldie, that BTW I ran really hot
last April. I love my old heavy cast iron head. Will
not argue the science of heat dissipation, but I know
what I like and feel good with.
Same for 3 -v- 5 main bearing crank. I know 5 should
be better, but I have heard some reports that the back
bearing does not get oiled properly all the time, and
can cause wear quicker than in the 3 main setup. Who
knows, just gives me justification to like what I've
got!
Mike Harper
'66 3 mail, iron head
Charleston SC
--- Adam Bradley <ambradley@yahoo.com> wrote:
> Well I've never had a CI head and am not a race car
> driver or an
> engineer, but nearly every R16 I've owned has
> experienced head warpage,
> and they all had aluminum heads.
>
> My first RL411 warped after I owned it for six
> months, although there
> had been symptoms for about a month before that. My
> first Roadster
> warped when I put the engine back in after replacing
> the clutch, then
> again when I moved the engine from one car to
> another. I'm assuming it
> was due to too much air in the cooling system that I
> didn't "burp"
> properly each time.
>
> My last one had very minor warpage around some water
> passages that may
> or may not have contributed to the head
> gasket/overheating problem.
>
> My question isn't which is better, but has anyone
> with CI heads had
> head warpage? I thought it was nearly impossible...
>
>
> --- Christopher Coker <cfcoker@home.com> wrote:
> > I have to agree here. Aluminum's heat dissipation
> qualities are
> > preferred
> > over those of cast iron. You save a significant
> amount of weight
> > too. Make
> > sure the cooling system is up to the task of the
> increased hp, and
> > warping
> > shouldn't be a problem.
> >
> > I have a cast iron head on my race car right now,
> but only because
> > that's
> > the way the car came. I have three bare aluminum
> cylinder heads as
> > spares.
> > When I build up the three-main motor over the
> winter, it will have an
> > aluminum head on it. Right now I'm hoping to get
> 140-160 horsepower,
> > and
> > will go up from there.
> > > From: "Henry Bahn" <hbahn@home.com>
> > > Reply-To: "Henry Bahn" <hbahn@home.com>
> > > Date: Fri, 3 Aug 2001 15:17:13 -0400
> > > To: <datsun-roadsters@autox.team.net>
> > > Subject: iron head
> > >
> > > We had this discussion about a year ago, and Joe
> Hauser pretty much
> > put it
> > > to rest. The alum.head has better heat
> dissipation, not worse,
> > than the
> > > cast iron head, and is not more likely to warp.
> Claims of
> > increased HP from
> > > the iron head just ain't so. I don't think
> anyone is using CI
> > heads for
> > > competition roadsters.
> >
> > Happy roadstering,
> > --
> > Chris Coker
> > 69 1600 SPL311-24529
> > <http://members.home.net/cfcoker/roadster.html>
> > 6? 1600 GP Race Car
> > <http://members.home.net/cfcoker/racecar.html>
> > Royal Oak, MI
>
>
> =====
> Adam
> '70 1600 SPL311-28181
> http://www.picturetrail.com/abend
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