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Message
Arn't you jumping the gun a little here?
Don't worry, I
haven't done anything yet. It's just in my nature to over-analyze
every option, which is bad enough for me, but the real victim is my poor wife
:-)
It's true that you're
providing us all with a useful list of things to avoid, and lots of good
wholesome entertainment,
Don't make me have
to come down there mister :-)
but
you're also "experimenting" in the true sense of experimental. It caught my
attention when Ed mentioned that he was on his fifth intake, and Tracy said he
didn't love his rotary until 80 hours. Perhaps you're giving up too early on
this.
I haven't given up
yet, but I am trying to sort out the facts. Aside from the performance
issues, the plane is overweight, and very nose heavy. Losing the turbo,
huge radiator, etc could net me 30-50 lbs of weight savings from the nose,
which would do wonders for my CG. Lot's of things
to consider.
Lets take a step back for a moment. Forget about altitude. On the
ground, and for say the first 3000 feet where you'll be doing most of your
climbing, its a known fact that the turbo 13B produces considerably more horses
than the NA version.
The stock turbo
only made about 20% more HP than the non-turbo, and that was at 5.5 to 6.5 psi
of boost. Ed's promising us all 15% with just some tuning (and a dozen or
so intakes <g>).
The cars, running at the same altitude,
don't blow their turbos and engines to bits, even at much higher RPM than you're
doing. So whats the difference?
Cars have intercoolers,
and lower compression rotors. They also probably have about a hundred
million yen worth of development to make sure they don't blow
up. Even with all this, the stock 3rd gens, running 10 psi of boost
blow up all the time. In fact it's rare to ever see one with more
than 100k miles on the engine. My 93 had it's engine replaced at 60k
due to a broken apex seal. I didn't own it at the time, but it's an all
too familiar tale. Of course, you can blame this on the owners who
may accidentally run a tank of regular, or the oil metering pump, or whatever,
but if that's all it takes to blow the engine under boost, it bears some
concern. Of course altitude is the key factor, since cars are on the
ground where it's safe. If I blow the FD engine, I roll to the side
of the road and call AAA
:-)
Why, at these
altitudes, should you're engine perform worse than the one in a
car?
I suspect that it isn't
performing worse than a car. I just believe that the turbo
car engine doesn't surpass it's NA brother until it reaches about 4
psi. I'm deciding if it's worth running that much pressure just
to break even. On one hand, Bruce scared me by guessing that I
shouldn't exceed 2-3 psi. On the other hand, 4-5 psi
of boost means nothing if it's only producing NA power. The only
real concern is the higher intake temps down low, and the risk of
pre-detonation. Bruce also told me of a customer running the
exact same basic engine in a car, with 17 psi of boost, who's putting out
350 HP on a chassis dyno. Believe me, I ask myself every
day why I'm worrying about 7 psi and 200 or so HP
:-)
I really DO want to
keep the turbo, but only if I feel safe running it hard enough to get some
advantage out of it.
Thanks for adding fuel
to my dilemma :-)
Rusty
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