Doug
I think what Dave was trying to say is that at Bville the altitude lowers
the bar to about 25" Hg, so we need to increase boost to compensate. If the
compressor is sized to accommodate these changes, the power will be the same
as at sea level. It's not the gasket problem. If they live at 600+ HP at
sea level they will live at altitude.
Unfortunately many of us overlook the difference in barometric pressure in
compressor sizing. We gotta build for where we are gonna run.
Actually, given enough time and money, Kenny could probably have overcome
the gasket weakness. The multi layer steel design gaskets can be made for
any configuration and will contain unreal cylinder pressures as long as
consistent clamp load and cylinder head lift are controlled. Thats the
problem working with stock components. Castings are designed for specific
power and strength/weight and have limits. Even with analytical approach in
design, when we triple and quadruple cylinder pressures, strange things
happen.
Most engine builders that utilize truly high cylinder pressures, utilize an
old design called a "Coopers Ring" or a simple high pressure gas filled
metallic "O" ring. My choice on the turbo motor is the metal O ring and an
otherwise dry deck. It is complex, costly, and difficult to machine, but
extremely effective. Even with some cylinder head lift, recovery of the O
ring provides good sealing integrity.
In contrast to what I just said though, the first MLS gasket I saw was in
the mid 80's, made by Cherry gasket co. in Japan. The gasket I saw was for
the F1 Honda turbo motor, was 5 layers, solid center, two embossed layers
and two smooth layers all sandwiched together. I suppose it held 5 to 7 BAR
boost pressure. I wonder what cyl pressures would be experienced with
1.5Litres making 1200 HP @13000 rpm or thereabouts.
Dave?
Must say the sealing community at Fraud was VERY impressed. We began a MLS
program for the 4.6L engine with Ishakawa and later FelPro. Now about
everyone makes some version of MLS. Some better designs than others. We
need to remember though these are jus very sophisticated copies of the good
old steel shim gaskets of the 60's.
Have a good week everyone, we're off to Wyoming again on Tuesday.
Rick
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