[Healeys] Intake to Exhaust Manifold Gasket

[Bob Spidell]

Harold,

The gap you achieved looks normal to me.  I have similar on my BJ8, 
which I overhauled a couple years ago.  The gaskets I purchased from 
Moss were much thicker--I didn't measure them, but I recall thinking 
they were between 1/8" and 1/4"--than the ones in your photo, and they 
looked like cork impregnated with something (looked like rubber, but 
that can't be, can it?).  Seeing that Moss charges almost $5 for the 
thin gaskets in your photo, stacking 3-4ea in each 'gap' would amount to 
a ridiculous amount of money for them.  When I rebuilt my engine a long 
time ago, the gaskets kinda disintegrated over time anyway, and I didn't 
see any ill effect.  In a V-type engine (6 or 8) with a carburettor, hot 
coolant gets circulated around the base of the carburetter to offset 
'carb icing' due to the cooling effect of the fuel being vaporized (my 
dad's '55 T-Bird has a flapper valve that gates hot exhaust gas to the 
carb, and is supposed to shut off when the engine gets hot but I doubt 
it works properly after all these years).  Anyway, the intake manifold 
is stacked on the exhaust because 1) the exhaust manifold heats the 
intake to offset the evaporative cooling effect and 2) that's the only 
place it can go (unless you have a 'cross-flow' head design, like on the 
100S engine).   I can only guess the gasket is there to somehow modulate 
the heating effect but, since it's just a damn gasket there isn't much 
it can do.

I'd call Tom Monaco at Tom's Import Toys and ask him.  He's a Moss 
reseller--at a 10% discount--and may have a (very colorful) 
explanation.  Otherwise, check around and see if anybody has the 
'proper' thick gasket and, if not, you can either pay Moss' ransom or do 
without them.

Bob

On 11/17/2019 12:04 PM, Harold Manifold wrote:
> Hello,
> I need the advise of this esteemed forum once again.I was dry fitting 
> the exhaust and intake manifold and noted the holes didn't line up 
> properly on the head side. I used washers as shims until the holes 
> lined up and ended up with a 0.171" gap between the two manifolds. See 
> the pictures. The Moss gasket I have (021-429) is 0.047" thick. It 
> would require 3-4 gaskets to properly fill the gap. Is there another 
> gasket that is thicker? The BMC part number for the gasket is AEC950. 
> I seem to remember the original gasket was thicker but it got 
> destroyed during disassembly. Is this a case of switching to a 
> non-asbestos modern gasket material?
> One solution is to use multiple gaskets. Is there a better solution? 
> Car is a 1960 BT7 Mk1 2 Carb.
> Thanks ... Harold
>

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