Del Cecchi wrote:

"trainfan1" wrote in message
...

K. Smith wrote:

trainfan1 wrote:


K. Smith wrote:


That's the exact issue runaway your marketing is based on your
"claims" & every single time they're independently tested (so far)
you are found out as fudging. When independently tested a Merc made
the claimed 250HP (+),



On premium fuel, required, on a factory hopped-up motor...


The article makes it clear the Bomb people were there prepping their
motor also, so I'd say it's independent testing, the losers will
always have the dealers making excuses. In this case the Bomb engine
was 13HP below the Merc that's a fair bit of HP.


a Yamaha was slightly under it's claimed 250HP & your engine Co's


was way down on HP & to some users more importantly; torque.



BUT the peak torque comes in at a lower & more usable rpm...


I think that's a fair comment & probably it would have been relevant
if the engine made the claimed HP as the others in the class did, but
when it's only a 239HP engine it sounds like the dealers are trying to
still sell no matter what???

Remember these engines are thousands of dollars dearer than the
competition, not hundreds but thousands!!!! Where is that extra money
going?? certainly we can't see it going into the engines which are
simple old style 2 strokes with a ficht injector system??? No multiple
variable timing cam shafts,multi valves per cyl,super chargers,world
leading & proven GM technology base?? none of that with these super
priced whipper snipper motors.

The clear suspicion needs to be that the "extra" money is being thrown
at the dishonest dealers so they'll flog them & say/do whatever it
takes to make their windfall profits. There's no way the dealers or
bomb will ever admit any of this indeed the rebate, subsidy, training
BS money return schemes are so well hidden not even dealer staff are
aware. The same marketing ploy was used to flog the Fichts & the
dealers of course even in this NG denied it all day long, till the
bankruptcy court uncovered the truth when the dealers tried to recover
the kickbacks. Which was Her Honour found the dealers had extracted
30% post retail sale kickbacks & that they were never entitled to
them, indeed we were hoping she'd refer them for resale price
maintenance:-) The dealers were flogging known defective ficht engines
for extra money (one even made it clear they'd said they'd stop
selling ficht unless they got bigger rebates etc).

Now these dealer idiots think they can run the exact same scam &
nobody will say anything??


A name change doesn't clear the slate,



It's more than a name change - & you know it... actually you probably
don't...


It's nothing more than a name change, all the claimed "improvements"
are about trying to get enough engines to hold together long enough
that the dealers will sell sell sell for their super markup??.

How does a treated bore stop detonation??

Better & more even heat transfer to water jackets eliminating hot spots
in the chamber.


How do high melting point pistons stop detonation???

Endothermic friendly metallurgy promotes heat transfer from hot piston
centers & to cylinder walls & water jackets. Lowers & evens cylinder
temperatures reducing detonation.


Could you explain what "Endothermic friendly metallurgy" is?

No.

Well, the alloy used in the pistons can absorb and transfer heat more
readily. If they had to, they could even go to ported pistons for even
more transfer.




How does high temp oil & then even less of it stop detonation??

Low ash high temp oil has a higher flash point, resisting
combustion/dieseling syndrome, reducing detonation.


I thought they used TCW-3. Do they require some unusual oil to be
reliable?

Only if you commit to it and have the engine rigged for it.



How does an impact injector/garden hose nozzle combo provide enough
atomisation to stop detonation???

It doesn't. The combination of chamber shape, heat dissipation,
cylinder, piston, & head materials, as well as coatings, all affect
flame travel, & tendencies toward detonation or not. The injector
system, however you may "want" to characterize it, is at the end of the
whole process. Controlled by a properly programmed ECM, the injectors
should provide an optimum charge, atomized enough for good combustion,
and in sufficient quantity for additional cooling of the
compression/injection stroke, with proper droplet size, all to attain
stoichiometric proportions in the approach to complete combustion.
This is the balancing trick - and hence the other tweaks - the lean
charge must also be enough to complete the cooling process too.

I didn't know gasoline absorbed that much heat when evaporating. Is this
really a significant factor?

In 2 strokes it sure is. The fuel is part of the cooling system.

And saying what the "properly controlled by ECM injectors *should* do
sort of begs the question of what they actually do.

Well, a 14.7:1 A/F Ratio is ideal, but not attainable in practice, as
there is not enough time in direct injection to vaporize the fuel. A 2
stroke will leave behind some exhaust gasses too. The injector must be
able to atomize the fuel into droplets small enough to approach vapor,
but large enough to absorb some of the heat of combustion. What E-Tec
is trying to do is minimize the losses associated with overlapping
strokes in 2 stroke design theory, while using as little fuel as
possible. The chamber design is very critical.


How does running an engine at power on hugely lean mixtures stop
detonation??

This is the balancing trick - and hence the other tweaks - the lean
charge must also be enough to complete the cooling process too.

it caused the base heat buildup that starts detonation.

How does a beefed up huge extra drag gearcase stop detonation??

Keeps the Sidewinder/Switzer kids from picking this model to run WOT
all day long up on a jack plate...


Better not put one on your bass boat. Those guys love their jack plates.
And they love WOT.

I just made that up.


The answer is none do: all those things are a lame (is not an MP3
emulator:-)) attempt to make the engines able to withstand the
inevitable detonation consequences when run lean at power on poorly
atomised low pressure injection with very questionable lubrication.

Thanks for the E-Tec spruik Rob but hey I'm sure you got a lucrative
deal to fit them?? much more dollars than the other brands???

You REALLY don't know me...

but what is it to your advantage to de-spruik something you don't
understand?



Always looking for technical details. The geekier the better.

del


I can see the dilemma and confusion K. Smith is facing, but the engines
do work. The BRP units are an improvement over the OMC offerings, which
did have isolated issues - as there are thousands still in use.