I'm no expert by any
means, but the higher water temps do not
surprise
me.
As I understand
it, the exhaust porting on the Renesis is
completely different than the
13B. The exhaust runs much cooler in the
Renesis because of this, so I'm
told. It is likely that a significant
fraction of the heat that is not
going into the exhaust is going into the
water jacket instead.
True, the EGTs on the Renesis are much lower (by
about 250 degrees) but the reduction is supposed to be due to a combination of
less unburned fuel in exhaust, later opening of exhaust ports and higher
compression ratio. These should all result in better fuel efficiency and
power. But yes, part of the heat is apparently finding it's way
into the coolant unless I have missed something.
The car folks
probably won't sense much of a change in water temps
because they
typically have a lot of margin in the cooling system. You, on
the other
hand, have a cooling system that has very little (if any) extra
capacity.
True, but I was hoping some of the racing crowd (who
don't usually run thermostats) had swapped a Renesis into an existing car
and perhaps seen a coolant temp change like I did. Or maybe a dyno
operator who noticed a higher coolant temp rise through the
block.
I haven't seen
anyone do this, but I would think that it would
help the cooling if an
effort were made to course the cowl air close to the
engine cases and/or
the oil pan instead of just letting it blow anywhere it
pleases inside the
cowling. A finned (or ribbed) oil pan might help too
without adding much
weight.
Believe me, in an RV-4 cowl, the air has no choice
but to pass closely over the engine & pan. There's no other place
for it to go : )
It sounds like
you are not after much additional cooling, so small
changes like these
might be enough.
Bill
Dube'
Actually, it's a big bucket load of
cooling. Calculate the energy required to heat 30 GPM of
coolant by 15 degrees.
Figured out a way to test the exhaust heat
theory. I'm installing a temp sensor in the engine heater
port. This is after the coolant has passed over the combustion chambers
but before going around the exhaust ports. My existing coolant temp
sensor is positioned at the water pump housing outlet which is after
both. The delta temp should represent the heat added by the
exhaust.
Tracy