I don't know for sure what happened with Ed's seals but offer this
observation FWIW.
Although the RWS seals developed with Bruce are harder than the Hurley
seals, that is not the factor that I think is most significant here. It is
the resistance to fracture that matters.
It's hard to put numbers to this but it is very clear when you take one of
each in hand and snap them in two. Unless you are a lot stronger than me,
you can't break the RWS seals with bare hands but I can easily break
Hurleys. I'll bring samples of each to Charlie's fly-in on Memorial day
weekend for demos.
Nothing is immune to failure of course. We recently had an irate
customer (drag racer) who was upset that the seals bent down in the center
during detonation at high boost (> 30 psi). The seal was forced down
into the groove so hard that the spring stops on the two ends bottomed
out and the seal sagged in the center. This caused the engine to have low
compression but no damage to the rotors or rotor housings. He said this
bending never happened with Hurleys. I'm sure
it doesn't because Hurleys would be in many pieces under the same
conditions. Which would you rather have happen? His
answer was neither. Sigh........
Tracy
Lynn,
The current question seems to be the hardness of the "Hurley"
seals that failed
in Ed Anderson's 13B relative to "Tracy's" seals or even stock
seals.....Also the
wear of his apex slot seems to be a factor........Correct me if I am
wrong but I believe
your 12A engines use 3mm carbon racing seals........If this is so I would
presume
they are much softer than stock seals.........How much racing at 8-9000
rpm do you
get out of them and where are the wear patterns located........seal
surface,side etc ?
Thanks,
In a message dated 04/24/2005 02:53 Central Daylight Time,
finn.lassen@verizon.net writes:
<< Ok, so grooves don't wear in your application (car racing) with proper
lubrication and air filtering.
What HP range would you estimate your engines spend 90% of their time in?
Finn
>>
We record and review each session on a video camera that watches a special
set of gages. I show the driver where he has dropped off of the power and he
complains about having to shift up here or down there and so on. We may then
change rear end ratios to get him out of a shift in a fast turn or such.
He is attempting to stay above 8,000 RPM. Max power is at 9,400 RPM and
shifts are at 9,600 RPM.
HP at 8,000 is 223 to 225. Max power is 244 to 245 HP at 9,400 RPM.
Lynn E. Hanover