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Science has progressed at an
amazing rate in the past 100 years, yet there is still widespread resistance
to accepting how much
we still don't know.
Surprisingly, this resistance is common in the scientifically educated
community - where you would
hope
the most enquiring and curious minds
would be...
In 1994 I had a conversation with 3 guys from an engineering college that
were in the Formula SAE competition. This is a
contest in which the students build a race car using a motorcycle engine,
and then compete against teams from
other schools all over the USA.
Anyhow, as we were driving down the road in my van ... I
told them about how my customers were winning everything in sight at the
motorcycle races
using my High Velocity Ports. The first thing they
all said was:
"Yeah ... but what about 'Supersonic
Nozzle' ..." ?!?
"
Super - Sonic - Nozzle
??? "
That was the funniest phrase I'd heard in a long time, and the more I
thought about it, the funnier it got. Pretty soon I was laughing so hard, I almost
lost control of the vehicle....!!!
"No, seriously", they said, "supersonic nozzle is why small
ports don't work ... we
learned it in engineering school !! When a gas reaches the speed of sound
(supersonic) the flow becomes really turbulent, creating a huge nozzle
effect (restriction)." ...
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MotoMan Says:
I'm not saying that the supersonic nozzle effect doesn't exist. For example, if
you wanted to get the maximum amount of air to pass through a pipe as fast
as possible, you wouldn't want to restrict it with supersonic turbulence.
Of course the solution would be to make the pipe bigger !!
But, the problem with applying that idea to engines is that it assumes
that engine airflow works the way it does on a flow bench ... that port
flow is a constant steady stream. It also assumes that the cylinder is only filled
by the
action of the piston, and ignores the charging phenomenon.
This is
an example of "half science"....
Which is when a
phenomenon is observed and found to be true,
and then incorrectly applied
to another situation.
What's Actually Happening:
It's true that at the peak of intake port velocity, high velocity porting does
cause the airflow to reach and even exceed supersonic speed, and the
"nozzle" causes the port to not gain any more flow at that point
in the cycle. The flow is momentarily restricted, but it's
important to note that that doesn't mean it stops flowing air !!
When the port velocity slows to below supersonic, and the piston is returning up again, the charging effect overcomes the loss
created by the dreaded
SuperSonicNozzle
!!
The overall effect is a net gain in cylinder filling over the intake
period.
Back To The
Engineering Students
The big problem is that the students had automatically closed their minds
to exploring &
testing that area of engine technology ...
... because an "expert" said it wouldn't work !!
The saddest thing of all is that now 8 years later those engineers could
be on the cutting edge of the automotive industry ! They should be leading the way
and in control of their own careers, instead of just "following the flock".
Check things out for
yourself !!
Try This Experiment:
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The next time
you're at a really wide flat expanse of land or sea, take a look at the
horizon. Next, take a look at a full moon on
a clear night.
What Do You See ??
You'll notice that the earth really is curved and the moon actually looks spherical !!
"Experts" once
said that the earth
was flat & everyone just believed them.
The earth didn't suddenly become spherical because a scientist proved it was, it was always that way !
Truth is self-evident, when it's so obvious. Still, people have been known to deny even
the exceedingly
obvious.
Why ??
It's all about "the box".
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Despite all the logic
& overwhelming
race victories, why is the idea of smaller ports still
so hard to accept ??
Once again, it has absolutely nothing to do with
reality,
it's all about "the box" !!
Here are some thoughts about small ports:
1)
It seems to
good to be true.
(Cynicism is fear.)
2) Some people who have always thought "bigger
is better" will find it hard to do the opposite, because it implies that their way was wrong.
(We're told all our lives
that wrong = failure, and that failure is to be feared
at all costs.)
3)
The idea of smaller ports begs the question: why
wouldn't the manufacturers
make the ports smaller in the first place ???
(It's scary
to think that "experts" would suppress knowledge & technology.)
4)
Smaller ports
are all about the net gain in flow, rather than the instant
satisfaction that
comes from seeing a "flowbench" gain.
(The idea of giving up instant gratification now, for a much bigger gain later is
a scary concept.)
5)
It would have been published in the mainstream
textbooks
& magazines.
(It's scary to think that the media
doesn't have knowledge of all things, or that they don't always tell the truth.)
6)
For some people it's simply a matter
of:
" That's not the way everyone else does it "
(Most people find it impossible to think differently than
others, out of fear
of being ridiculed.)
That's right ...
Fear
makes up the 6 sides of this type of "box"
Q: Who makes the "Box" ???
A: We build it ourselves, gradually over the course of a
lifetime.
Once he becomes aware that the box exists, every man must make a conscious
choice to stay in it.
Therefore, every man is also equally free to escape from it.
Hey ... I just thought of a
funny
new way to say "Think Out of The Box" :
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MotoMan
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Don't Get Sucked Into The
m
m
m
m
m
m
m
m |
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What's one of the best ways
to escape the
powerful
'thinking vacuum' created by the SuperSonicNozzle
???
Hi Velocity Port Your Own
Cylinder Head !!!
By doing it yourself, you'll not only
get more power for your engine, you'll also refuse to accept "the box"
!!
ARTWORK
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The way it works is 100% science, but since you're
really creating a 3D sculpture, high velocity porting is more like art
than any other aspect of engine tuning.
But you don't have to be Leonardo DaVinci or Pablo Picasso
to do it !!
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You say you're not an artist ??
By taking your time and following these guidelines,
you'll be surprised at how much natural artistic ability you have. |
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Gravity will naturally level the epoxy. Since the roof
of the port slopes down at a constant angle, the epoxy floor
"automatically" makes the correct
funnel effect. |
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Next, match the epoxy near the valve bowl to the
existing circle created by the valve seat. Don't enlarge the opening, just
match it, and you'll get a perfectly shaped valve pocket.
You're half way there !
From there you carefully sand the floor down to the correct height as
described in the past issues...
You can see if a flat surface is level, right
??
It's easy !! |
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Once the choke point height is set, then sand the radius
smooth as described in the past issues...
Then sand the entry radius smooth.
You can feel if a radius has a nice
smooth
curve to it, right ??
Right on !! |
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Carefully blend the transition from the manifolds into the port. You'll
have to remove them when you sand out the epoxy. Since they aren't
numbered, I use a grinding stone to mark the rubber manifold. The arrows
point to the 2 marks, indicating that this one's for port #2 !!
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You are now hereby officially
qualified to High Velocity port your head !!
Go For It !! |
The Bandwagon
I've seen lots of discussion forums & chat rooms discussing the latest Power
News articles. Many people are asking the others: what do you think of smaller
ports ??
What if I told you that the best tuners, producing the fastest engines at the
highest levels of world competition used this technique ???
or
What if I didn't say that ??
Does it change the logic of the last 3 issues of Power News ??
Who cares what everyone else thinks ...
what do you think ???
It's a fact that most people want to be on the popular side.
If it seems like "most people"
support an idea, then the vast majority of
people will find it safe to jump on the bandwagon
in spite of the truth or falseness of
the idea.
Plenty of "bandwagon" riders have fallen off the cliff and crashed.
The
" human nature " of the bandwagon effect is a serious liability to
logical thinking.
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Power News
isn't about the bandwagon.
It's about having the strength to think and act on
ideas based on logic ...
... not because "everyone else thinks so ". |
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Getting off the bandwagon
ride gives you a new kind of power ... don't you agree ??
Do the manufacturers know about high
velocity ports ???
Of course they do.
m
Many of the magazine new model shootouts and reviews are subjective and offer
few
deep insights into how engine performance is actually improved from year to
year. But if you're
reading carefully you can sometimes "connect the dots" about smaller
ports !!
Here are 2 examples that come to mind:
1995 CBR 600f3 "Intake porting changes" are one of the listed
improvements from the previous f2
1998 R1 "the valves are 1mm smaller than the previous FZR1000 Thunder
Ace."
Both models were clearly better than their predecessors, and both made use
of
higher velocity (smaller) intake ports !!
Introduction To Exhaust Porting:
Here's more evidence
of the difference between what is commonly thought and what is actually true.
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2001 GSXR 1000 / 145 horsepower
Exhaust Port Diameter 1.160
inches / 29.5 mm
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1988 FZR 400 / 45 Horsepower
Exhaust Port Diameter
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Let's do some detective work !!
Why does
the most cutting edge horsepower sportbike of 2001, the GSXR
1000 have exhaust ports that are only about 8 % larger than a
1988 FZR400 ... especially considering
that
the 1000 has 250 % more displacement ??
8 % = 250 % ...
huh ??
Of course the 400 revs higher, but the difference is not enough to
make up for this rather huge math "problem" !!
Do you think that somewhere, some tuners have unknowingly lost power
because they decided that the "hot set up" on the GSXR1000
should be to enlarge those little exhaust ports to make
them
"Flow Better" ?? 
Do you think that somewhere, some tuners have unknowingly lost power
because they decided that the "hot set up" on the FZR400
should be to enlarge those little exhaust ports to make
them
"Flow Better" ??
Another way of looking at it would be to say "don't enlarge the
exhaust ports on your 400 unless you're sure you can get more than
140 hp from it !!
Did you ever see a 140 hp FZR400
??
...how about a 280 hp 800 ?? ... or a 350 hp 1000 ???
It starts to get clear when you think this way.
Don't Enlarge Your Exhaust Ports
!!! Most Are Waaay Too Big Already !!
"MotoMan"
Has A Brief Conversation With
"Hearing-But-Not-Actually-Listening-Man".
H-B-N-A-L-M: If smaller ports really
do make
more power, then why wouldn't the manufacturers make the ports the correct
size in the first place ??
MM: By
gradually reducing the port size in small increments each year, they can
easily add
more power and thus offer the "new and improved" version with a
few
more horsepower than last year's model.
H-B-N-A-L-M: No way...
the manufacturers would all have to agree to that, because if one factory
broke out and made the ports really small, business competition would force the others
to make their ports smaller also.
MM: They
cooperate with each other, the competition is mostly an illusion.
H-B-N-A-L-M: No way ...
sorry, I just can't believe that.
MM: Okay,
well then you've
got to believe that back in 1991 one guy working out of his house for 3 months with a $2,000 flowbench out
smarted 4 industrial giants that have
employed thousands of the world's finest engineers doing 50 years worth
of R&D with billions of dollars at their disposal and they still
haven't figured this all out yet.
H-B-N-A-L-M: Hey,
MotoMan, that's a run on sentence !!
MM:
OOoops, you're right !!
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Stay Tuned !!
Exhaust Porting Part 2 ...
... in the next action packed issue of Power News !!!
Have a Cool Day Everyone !!
~ MotoMan
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