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Dynos prove most everything, other tests prove the rest (air flow notes)
- Subject: Dynos prove most everything, other tests prove the rest (air flow notes)
- From: mark kibort <mkibort@xxxxxxxxxxxxxx>
- Date: Mon, 30 Nov 1998 15:27:25 -0500
Message text written by INTERNET:[email protected]
>Here's my problem with your dyno gains... the car is sitting still!
Consider a well-designed ram-air kit with a huge properly designed
intake funnel. It would show no gains in a dyno test. But at 60mph,
the ram-air intake might actually provide a huge positive effect.
Maybe. The dyno won't tell us, though.
<
>>>>>>>>>>>>>>>>>>
Hi Brian,
Ram air and huge positive effects!!!????????????
Ok, Ill try to respond without getting excited. Yes , you are right .
Sometimes static dyno test will not give the =
increases a dynamic run . But , I thought of this too. If you followed=
me in my testing you would notice that =
I ran the pressure/vacuum tests at speeds up to 120 mph. The tests show=
ed
no, nothing, "0" gains of ram air at =
speed. all you could hope for is temps closer to ambient which could gi=
ve
you something.
So, I measured .5 psi vacuum in the air box inder full throttle at 120 mp=
h
in 4th gear at 5-6000 rmp ( 6000 rpm in 3rd was 100mph)
The test was very dramatic, as the needle started going to vacuum right a=
t
4500 rpm and was at its max at 5000rmp. This proves that the air going t=
o
the engine was less dense. the Fan ON created a slight pressure that
started at 3500 rpm and went all the way to red line as the fan is able t=
o
produce the air mass flow needed to match the engines 250 cfm to 500 cfm
(V8 4.7liter).
Now statically, on the dyno, the pressure guage did the same thing. Now
this all makes sense to me because of my background
In air flow theory. You really have to thing of the intake system and lo=
ok
at the potentials . at 60 mph, put out a big book , hold it flat . (=
do
you think you could hold it? well you can as the forces is only about 20=
lbs, and divide that by the area and youll get avery , very small number.=
=
If you were going 120 mph, you may get 1 psi. Now the problem becomes =
,
how do you get it down a tube to my engine????? This is the killer,
every turn and bend takes major energy out of the ram . A funnel as you
suggested , is not the answer. =
Here is why, what happens to the air in an intake funnel.? What the=
air does is it doesnt compress like you would think, it actually does the=
opposite. Yes, the air speeds up in the neck of the funnel but the
pressure goes down. Yes , now you have faster , less dense air, and les=
t
pressure to push it thru the system.
Second point. The ERAM moves air at speeds well above the engine's
requirements, thats how it develops pressure, by being somewhere in the
middle. (axial flow fan theory) At speed, the fan unloads and actuall=
y
is more efficient as it now speeds up and is able to absorb the electric
motors HP more efficiently. =
>>>>>>>>>>>>>>>Consider your ERAM fan. Sitting still it may provide the
gains you
claim. But at 60mph, there's a reasonable chance that your fan will
actually be slowing down the air rather than speeding it up. A dyno
run tells me nothing interesting, except perhaps for a brief time
after I floor it from a standing
start.>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
See above for the answer for this. theFan is producing air flow at =
a
rate of 6-800 cfm, at speeds for a 3" diameter tube of over 100 mph, and
again, as the air speeds up , the fan unloads and moves air even faster i=
f
needed. Just the opposite of your discription. (ie just like a propell=
er
on an airplane unloads once you are at crusing speed, ) The eram is
pitched for dynamic speed and not static speed, so I am impressed that I
would get pressure under stalled conditions , but I did.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> 2. Ive seen the track times go down as Ive videoed every lap Ive eve=
r
> taken, and Ive taken a lot.
No offense, but that's way too subjective. You are selling the thing
afterall. =
Even people who have bought it can _honestly_ see gains that simply aren'=
t
there --
they _want_ to see them. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
I agree, I have way too much track time to even suggest that this will dr=
op
your track times. Heck,
I bolted on 45 hp and gain only .5 seconds on every straight away, as its=
not about only HP at the track,
but I want every 4-5% I can get my hands on. So, Yes, you are right ,
the 5 to 9 hp is not really measureable =
on the track. its more a mind thing.
I hope this expains why it does work and why I have been so passionate
regarding the responses to questions of RAM air.
Ive studied it, Ive empirically tested it, I feel I have a faily good
understanding of why things happen, but even for me, there is much to be
learned.
Remember, funnels speed air up and lower pressure. Diffusers, slow air
down and raise pressure. The speed of the engine air is really control=
ed
by the ports and valves. All Im trying to do is to increase the desity =
of
the air as this is key to most HP gains.
Hope this helps,
mark Kibort
ERAM www innoventions.org
------------------------------