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And some folks think me flying in an experimental aircraft behind and
experimental engine is dangerous - at least up here, few morons, even fewer
texting and the odds of him being behind me in my lane over taking me are slim
and (well for all realistic purposes) NONE.
Sorry to hear about our accident, Lynn. Makes riding out a tornado at
Sun & Fun in the engine Tent seem tame by comparison.
Hope you are feeling better soonest.
Ed
Sent: Sunday, May 01, 2011 2:30 PM
Subject: [FlyRotary] Re: Timing Question for Tracy
In a message dated 5/1/2011 1:28:10 P.M. Paraguay Standard Time, echristley@att.net writes: I threw
my back out again last week, and the drugs have my sleeping pattern all out of
whack. Last night, I spent
another 6 hours researching what other
people have done. One guy reported that he started loosing performance
with 2*
of split at speed. It was a boosted engine on a dyno.
The problem I have with the RX-7 forum is that they are all guys
looking
for ridiculous performance running street engines on a dyno. You have to
read between the lines on all of it.
He didn't go any further than 2*,
because of the performance drop off, but that fits perfectly with what you're
saying
about detonation.
I'm going to go with what I've got now,
but I'm seriously reconsidering recasting the mount for the trailing VR sensor
to take out split as a near future project. There is more to fear
from detonation that a little more low end emissions.
>
> That problem firing a double ended coil is the gap size on the plugs.
Use
> plugs you can change the gap on, and set the gap at .010" to
.015".
>
> I used those even with an MSD and never had the
problem. Remember the
> rotor is hauling the mixture past the plugs
like a freight train.
> AR2592 Autolite work fine. Same heat range as
NGK -10s. But usually
> $7.00 a box of 4 at Autozone. The open tip may
get better cooling than
> the NGKs
Ok, Lynn. That deserves
some type of reward for being a brain dead simple solution to the root cause
of the problem.
If you're not getting a spark because you've set up to
much resistance to the current flow, cut back on the resistance.
I
learned a bit more about this in the research last night. You have a
couple of very authoritative guys giving very
scientific and clear
explanations of why using a split coil won't work. You have another set
of guys going, "Really?
I've been driving that setup for the past 6
months." The differentiation seems to once again be boost.
So I'm
confident that I can run the single coil set using the wasted spark
on the trailing, and I can just swap out the plugs
if it looks like I
start missing when the engine is under load.
The ultimate goal, though,
is to have two totally independent ignition sources. The MegaSquirt guys
have worked out the
circuitry to run the stock coils or even COP.
The problem I have with that is that it puts ignition control back in the
little homemade box. I like the idea of having the two highly
resilient, time-proven ignition systems that will keep
right on clicking
if my fancy little computer goes tits up. I'll loose control of the
advance, but I can be confident
that the limp-home mode of 25* will drag
me to crash site.
And that leads me to my next question.
Operationally, what would be the pros/cons of turning off the trailing during
cruise flight? Will it allow deposit to build up and ensure the
plugs are fouled if I ever do REALLY need them? Or is
it just
putting a needless load on my generator in order to dump an incremental amount
of extra heat under the cowl?
The wasted spark thing only works on the leading plugs. One or the other
trailing housing will have an apex seal between the plugs and will light the
next dose of mixture. So leading only for lost spark.
Running without spark on the trailings just collects oil in the cavity and
ruins the plugs4 days ago . Been there, done that. Driver never noticed.
Because of "A" apex seal between the plugs the trailing spark must be
distributed, either mechanically with a distributor or crank angle sensor or a
system with two pickups 180 apart and one reluctor.
Then the lost spark leadings can be triggered from another system with one
pickup and two reluctors. Because it needs to fire twice per revolution.
4 days
ago the wife and I were waiting for a light to change at a 6 lane highway
in our pristine Dodge Minivan. A moron in a 6,000 pound Trooper II hit is from
behind at cruising speed. A witness said he had his head down and was busy
TEXTING............... .He fired us into rush hour traffic to the
curb lane on the other side, to the stunned surprise of dozens of
speeding drivers. Both seats failed. Seatbacks laid down flat. Both
went to the hospital. He has minimum legal insurance. I hired a lawyer. grand
Nephew of Woody Hayes. I am going to try for the salvage. I can fix anything.
That light had been green for them for a long time and they were up to speed.
Why we were not "T" boned with 6 chances, escapes
me.
I
used to build totals, and this will just be another one. So My wife can get a
newer van and I can drive this one in a few months. Still dizzy myself. No
sleep yet. When I close my eyes it plays over again.
Lynn E.
Hanover
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