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Exhaust &

Jeff and Davids,

on me: since water boils so much better at our cruising altitudes, do
you use PURE coolant and/or what psi radiator cap are you gambling on ?

I examined my radiator cap and it appears that spring pressure alone ,
not spring and atmospheric pressure regulates the system pressure.So
although there would be more bursting pressure on the hoses the system
pressure will remain the same at altitude. The factory engineers said 
the seals on my engine would  withstand 13 lbs when they specified a 13
lb cap. So without better waterpump seals im going to leave it at that.
Water cools better than antifreeze even though antifreeze raises the
boiling point. Here in the south I will probably shift from 50/50  to
60/40 but no more than that. Also the corrosion protection will diminish
with reduced antifreeze.

Your other post said you thought your pulses were fighting each other
and to seperate the exhaust pipes: that's not an augmentor problem,
that's an exhaust design and tuning problem (pipe lengths, diameters,
weld qualities, and shape).  

I was talking about seperating the left and right cylinder banks. For
now Im using the 8 1/4 lb factory equal length 3 into 1 cast iron
exhaust manifolds. Bayard duPont (200 Hp Ford in a Defiant) was talked
into one of these ejector things By Charlie Airesman. When BAyard's
didnt work Charlie had him seperate the banks. So did I.
By the way Charlie gave up on his Honda engine and is now using a
Subaru  engine.

 I don't know how cu.inches factor in; the CSA didn't mention
cu.inches. Nor did it mention total system coolant requirement, which of
course is weight. If that's actually radiator frontal surface area as
recommended by Ron Davis, I'd re-evaluate your overall system efficiency
before saying it's not enough, particularly with cracking augmentor
home-heating ducts and un-tuned engine exhaust..

Charlies  radiator was roughly the same cu  in as mine with 110 HP vs my
230 HP. I used the augmentor to make sure I had adequate airflow  to
test my radiator capacity. A 5.4 inch mannometer reading  is adequate
air flow.

radiator dimensions were 2.75"D
x 9"H x 12"W (15"W including tanks), 14 fins per in, with inlet size
recommended by Ron Davis at 15% radiator AREA (I get 108sq"), and	

Russel Sherwood is using a SVX engine in a Glasair  and he used  easier
way to size his radiator. On his test stand he used a massive radiator
and while running the engine with good airflow over the engine he
progressively covered up more of the face until the temperature started
to rise. His radiator volume came up in the 500 cu in  neighborhood as
did Bayard's 200 HP Javelin Ford.

Thanks for the thoughts. The fire in the ductwork thing  is something to
ponder. I have seen one of Delta's  Pratt JT8D's with a fire from fuel
spilled  in the shroud  with no Ill consequences .