NC hybrid setup/coolant blows heater core/how to avoid?

[Bruce Plecan]

What I do is, epoxy the 5/8" heater hose fitting on the manifold shut, and
then cure it at 200dF.  Then drill a 5/16" hole in it.  That is enough for
heat and defrost, here in Ohio.   If you want really good control over the
heater coolant, use a heater valve off a 87 Buick GN/Ttype, it's vacuum
applied, On, type.
  If when ya do the cam, on the passenger side of the water pump is a hole
in the water pump/block.  Tap that out and put a 1/8 pipe plug in, it.  Then
drill a 1/16 or 1/8" hole in it.  Also, a 1/8" hole in the thermostat.
    The above is just what works for me.
Bruce


> I know this is NC but I"ve exhausted my related Nissan/Datsun list w/ no
> good info.
> A few of us have sb chevy V8's and several have experienced heater core
> problems d/2 higher/greater coolant flows/pressure (I don't know
> specifically), they've replaced w/ brand new units and halfway thru
winding
> out and leaving another NSX (their ride, mine wouldn't do that;^) their
> heater core will fail again.
> They only discussed ways to just bypass the heater core which is simple
but
> I live in the often rainy pacific nw so need heat occassionally throughout
> the year and would prefer some sort of pressure reducer mini-manifold but
> I"m not familiar w/ what hardwar is out their or the simplest way to solve
> this.  I'm not sure if it's simply a matter of too much flow or pressure
or
> combo of both that fails them.  Mine's still OK but I haven't ran it very
> hard yet and want to preempt a painful heater core R&R etc.
> Ross Corrigan  /  Vancouver, Canada