Gene Kearns wrote:
On 25 Jan 2004 08:26:40 -0800, (Backyard
Renegade) wrote:
When I worked for GM, I specialized in Port Fuel Injection runability
problems. Personally, I find K's posts, which btw are on topic,
facinating. Everything she talks about brings back fond memories of
studying chamber readings on the occilliscope, and comparing them with
emissions readings... If you know what you are looking at, you can see
that K is pretty much on the mark here with *MOST* of her theory. So
go back to shilling the union threads Harry, hopefully most will
ignore you there too...
Scotty from SmallBoats.com
I've probably missed most of this foolishness, having killed K's
posts... I only see the flotsam, but it seems not much has changed.
For example:
(c) Old worn engines & new 2 stroke OBs allow lube oil into
the combustion chamber, this has the effect of reducing the fuels octane
rating.....
One wonders what the "old 2 stroke OBs" did. I foolishly mixed oil in
my fuel, thus causing it to enter the combustion chamber.... my bad.
I have no objection indeed encourage those who don't fancy my posts to
kill file me, as you have. However you need to read what I said before
you still throw rocks.
I accepted the old "mixed in the fuel" 3 strokes always put oil into
the combustion chamber, but went on to point out that it was by design
so the effects could be allowed for. The main point you missed was that
it was in the fuel, i.e. it was consistently going up the transfer port
into the chamber, whereas with the DFI it goes inconsistently, such that
at low revs very little gets carried up then when suddenly spooled up
the crankcase clears any "excess" buildup, it may or may not be a
serious issue, however it's certainly a valid issue to address, given
Orbital have been struggling with it since the early 90s
(d) The very small amounts of oil stay in the crankcase &
get hotter & hotter & hotter,
?? If the small amounts of oil "stay there" then they accumulate and
there are no longer "small amounts." One wonders why the crankcase
doesn't melt, since there is nothing to cool it. You know, somebody
should think of a way to liquid cool the hot sections of these things.
Gee you've been looking into my next Ficht threads Gene & thanks, the
small amounts of oil getting hotter & hotter are an issue.
Out of curiosity, are there any differences between DFI for the GM
engines and the DFI used by FICHT?
GM doesn't use DFI the only auto people currently are Mitsubishi &
Mercedes & even then on one model only. The auto people realise that
injecting raw unatomised fuel into the chamber is too risky for consumer
usage over time.
At what point does one consider
timing to be too far retarded for idle conditions... and why?
10 deg BTDC but you can catch up on that in the other posts.
What
are the deleterious effects to the engine?
The flamefront's propagation speed is dependent upon the pressure/temp
combo, the "fire" in a petrol engine is very short lived so the heat
dissipation can be controlled. In a two stroke OB the biggest surface is
the piston & it's totally uncooled (e-tech are now trying to flow some
air through tunnels in it but that won't work either).
If the spark is too late the burn instead of seeing a rapidly
increasing chamber pressure see a constantly reducing or static at best
pressure as the piston goes down, this slows the flamefront meaning much
more time for the piston to absorb heat, & given it's all but totally
uncooled, that heat can make the piston very hot, hot enough to exceed
the auto ignition temp of petrol (250c, 420f) & that leads to detonation
when the engine is quickly spooled up.
How many incorrect premises does it take to make a conclusion
incorrect?
PS
This has nothing to do with Harry, as far as I'm concerned. This is
about a poster that has boasted that she can post what she wants, when
she wants.... "you're not the boss of me"....
Yep that's right you control freak.
knowing that her 850+
line, mostly OT, diatribes inconvenience and likely cost other posters
money,
Desperation stuff however if you stop the OT posts which certainly
exceed anything I post them problem solved, mine will stop also:-)
since they are forced to download the chaff with the wheat.
This is about a poster that says screw you, I'm going to post the same
850 lines of crap along with half truths
Half truths?? gee that's generous Gene as far as I or anyone else can
tell they're all just outright lies, not a single word is mine they're
ALL Harry's own lies.
and irrational conclusions...
hate mail about a particular engine configuration. I don't get it,
maybe you do.
Candidly I can see why you're not gettin' any, you're another bully boy
control freak, so just kill file me that's all, problem solved.
This is no more on topic than screaming, "FIRE," without just cause,
during the movie Inferno. It is trolling, pure and simple.
Gee lets see there was a ficht fire at OMC, over 7000 casualty jobs &
US$1.3 bil of retirees' money!! If only they'd cleared the ficht theatre
when I first said "hang about; lean at power, low pressure DFI, poor
atomisation & iffy spark timing then no oil???" I smell smoke, smmmmoke;
ffffffire, ffffffffffire, FFFFFFFFFFFFIIIIIIIIIIRE!!!
Talk about a tragic movie:-)
I warn the crowd again e-tech's claimed improvements absolutely confirm
the original assessments were correct & ficht was doomed from the start,
they were experimenting with consumers' money!!!
Again we say they still won't work!!! not no how. To find out the hows
& whys you'll need to read the rest of the Why Ficht failed threads,
oops alas mean Gene will not be with us. What a shame:-)
K