well, i'll certainly look into that. when i got it i looked it over really
well and didnt notice anything sharp, but it wont hurt to go back and check
it out again.
i'll prolly go ahead and get the flow disrupter vortex wing vibration
dampener doohickey installed and see if that helps. might also check and
make sure i torqued the TB back on properly. thanks for all the info guys!
-adam
----- Original Message -----
From: "Canucker Trucker" <mal5@ualberta.net>
To: <dakota-truck-moderator@bent.twistedbits.net>
Sent: Wednesday, July 03, 2002 12:07 PM
Subject: DML: Re: RE: Re: Re: RE: Re: Help!! Get rid of the Z-tube??
>
> It could be just something that was missed during fabrication or
> something....
>
> --
> Canuck
> --------------------------------------------
> Y2K 4.7L 2wd 5spd
>
>
>
> "Stlaurent Mr Steven" <STLAURENTS@MCTSSA.USMC.MIL> wrote in message
> news:5F7587961057D211ABE9004095102F7803C5A9AC@ex.mctssa.usmc.mil...
> >
> > Yes...looked down the inlet portion of the TB unit to check for any
sharp
> > edges.
> >
> > I had the F&B/Z Tube and it was smoothed everywhere but never experience
> > what is occurring on your truck. .
> >
> > --------------------------------------
> > Steven St.Laurent
> > C4i System Engineer
> > C4i Engineering Branch, PSD, MCTSSA
> > MARCORSYSCOM, U.S. Marine Corps
> > Office (760) 725-2506 (DSN Prefix: 365)
> > "Never be content with somebody else definition
> > of you. Instead, define yourself by your own beliefs,
> > your own truths, your own understanding of who
> > you are. Never be content until you are happy with
> > the unique person GOD has created you to be."
> >
> > -----Original Message-----
> > From: Canucker Trucker [mailto:mal5@ualberta.net]
> > Sent: Wednesday, July 03, 2002 9:44 AM
> > To: dakota-truck-moderator@bent.twistedbits.net
> > Subject: DML: Re: Re: RE: Re: Help!! Get rid of the Z-tube??
> >
> >
> > From what I can gather from all the posts is that the problem may be
> caused
> > by the TB alone:
> > 1) Steve has the Z-tube only - no problems
> > 2) Someone said they have an F&B TB - no problems
> > 3) You have the problem with the stock airhat and the Fastman TB as well
> as
> > with the Z-tube
> > 4) You mentioned Fastman has had this problem in the past ...
> >
> > (thanks Dr. Watson)
> >
> > So here's my theory: It **MAY** be caused by a phenomenon call 'vortex
> > shedding.' Basically, as air passes over an abrupt edge, the boundary
> layer
> > will 'stick' to the edge for as long as it can, until finally releasing
> > (like an elastic band breaking). When the boundary layer lets go (or
the
> > 'elastic breaks'), it creates a vortex which vibrates the edge it was
shed
> > from ... At a particular wind velocity, the vortex shedding occurs at a
> > particular frequency ... if this frequency happens to be close to the
> > natural frequency of your engine or the TB mounts or something, it will
> > vibrate the hell outta it. ... so basically, the air velocity going
> through
> > the TB @ 2400RPM causes vortices to be shed at the same frequency needed
> to
> > shake the engine ... This phenomenon is the cause of the Tacoma Narrows
(I
> > think?) Bridge collapse (but in that case the wind passing over the guy
> > wires caused vortex shedding at the same frequency as the wires ... like
a
> > guitar string)
> >
> > This phenomenon can also be seen on most radio antennae as you drive
down
> > the highway ... ANYWAYS,
> >
> > So how do you fix it? --- disrupt the air flow where the vortex
shedding
> > occurs ... i.e. at the TB.
> >
> > To get around the problem of the antenna ripping off as you drive down
the
> > highway, DC wrapped a thin wire around the length of the antenna (take a
> > look at it next time you're at your truck)...this disrupts the airflow
> > around the antenna and reduces the size of the vorticies being shed.
...
> > you'll want to do something similar to your TB:
> >
> > You could try dremelling off any sharp edges that were left in the TB
> after
> > fabrication ... check the bore and the butterfly plate ... maybe round
the
> > edges of the butterfly plate ... any sharp edge that the air might get
> > 'caught up on' is a potential culprit .... it's tough to say what would
> > cause it without looking at it ... OR just before the air enters the TB,
> you
> > could make some kind of flow disrupter like you were planning. Maybe
just
> > some vertical fins in the Z-Tube. The key there would be to get the
> > disrupter as close to the TB as humanly possible.
> >
> >
> > Like Bernd said though, it's nothing harmful to the engine ... it may
wear
> > some fasteners out or your throttle cable eventually, but who knows?
> >
> > sorry for the length of my essay :) hope it makes sense.
> >
> >
> > --
> > Canuck
> > --------------------------------------------
> > Y2K 4.7L 2wd 5spd
> >
> >
> >
> > ""crm"" <tb.crm@verizon.net> wrote in message
> > news:007e01c222ab$e6f3e210$7c6445a1@vatican2...
> > >
> > > Steven, the vibration is felt in the gas pedal. it occurs when i
> > accelerate
> > > enough to where it would shift at about 2800-3000rpm. starts at about
> 2400
> > > though.
> > >
> > > it didnt happen when i had just the Z-tube on there though. i only
> noticed
> > > it after the Fastman TB. i had been told it was because of the lack of
a
> > > resonator from the stock airhat and it appears to have been amplified
by
> > all
> > > the extra air flowing thru the new TB. so last night i went back to
the
> > > stock setup with the exception of the TB. still had the vibration.
Bernd
> > and
> > > Dan Arcand both said it was nothing dangerous for the engine, but i'll
> > still
> > > see if i can fix it with the little vortex wing thingie inside the
tube
> > that
> > > they told me how to make.
> > >
> > > other than that, the truck really seems to be liking the mods i've
> added.
> > > i've got about 175 miles on it since the TB swap and PCM reset and i
can
> > > definitely tell a difference in performance. i'll prolly drive it
> another
> > > week and then take it back to the dyno to tell for sure. and then i'll
> > have
> > > another baseline prior to the cams and intake install.
> > >
> > > -adam
> > >
> > > ----- Original Message -----
> > > From: "Stlaurent Mr Steven" <STLAURENTS@MCTSSA.USMC.MIL>
> > > To: <dakota-truck@dakota-truck.net>
> > > Sent: Wednesday, July 03, 2002 10:26 AM
> > > Subject: DML: RE: Re: Help!! Get rid of the Z-tube??
> > >
> > >
> > > >
> > > > When I installed the Z-tube I never did experienced this problem.
> > > >
> > > > Where is the vibration occurring and what RPM range is the
resonation
> or
> > > > vibration is being felt, Adam?
> > > >
> > > > --------------------------------------
> > > > Steven St.Laurent
> > > > C4i System Engineer
> > > > C4i Engineering Branch, PSD, MCTSSA
> > > > MARCORSYSCOM, U.S. Marine Corps
> > > > Office (760) 725-2506 (DSN Prefix: 365)
> > > > "Never be content with somebody else definition
> > > > of you. Instead, define yourself by your own beliefs,
> > > > your own truths, your own understanding of who
> > > > you are. Never be content until you are happy with
> > > > the unique person GOD has created you to be."
> > > >
> > > > -----Original Message-----
> > > > From: crm [mailto:tb.crm@verizon.net]
> > > > Sent: Wednesday, July 03, 2002 7:51 AM
> > > > To: dakota-truck@dakota-truck.net
> > > > Subject: DML: Re: Help!! Get rid of the Z-tube??
> > > >
> > > >
> > > > just to let you guys know, i installed the stock intake last night
and
> > > still
> > > > had the vibration. so it's either always been there and i never
looked
> > for
> > > > it and therefore didnt notice it. or, it's all the extra airflow
from
> > the
> > > > TB, which in one sense is cool since it's obviously flowing more.
> > > >
> > > > either way, i am keeping both the Z-tube and the new TB. i bought
some
> > > stuff
> > > > last night to make a little vortex wing (or whatever it should be
> > called)
> > > > inside the tube so i might get to that this weekend. and even if it
> > doesnt
> > > > completely fix it, i'll not worry about it...
> > > >
> > > > thanks to all who offered suggestions!
> > > >
> > > > -adam
> > > >
> > > > ----- Original Message -----
> > > > From: "Bernd D. Ratsch" <bernd@texas.net>
> > > > To: <dakota-truck@dakota-truck.net>
> > > > Sent: Wednesday, July 03, 2002 12:04 AM
> > > > Subject: DML: RE: RE: Help!! Get rid of the Z-tube??
> > > >
> > > >
> > > > >
> > > > > The vibration is not due to the intake or throttle body...but
rather
> a
> > > > > resonance from the intake plenum. If you look at the factory
airbox
> > (on
> > > > > the TB)...you'll notice a resonance chamber (or two depending on
> year)
> > > > > which cut the noise to a minimum (if not completely).
> > > > >
> > > > > - Bernd
> > > > >
> > > > > -----Original Message-----
> > > > > From: owner-dakota-truck@dakota-truck.net
> > > > > [mailto:owner-dakota-truck@dakota-truck.net] On Behalf Of Ronald
> Wong
> > > > > Sent: Tuesday, July 02, 2002 6:03 PM
> > > > > To: dakota-truck@dakota-truck.net
> > > > > Subject: DML: RE: Help!! Get rid of the Z-tube??
> > > > >
> > > > >
> > > > >
> > > > > I have no problems with a K&N FIPK but then I have an F&B TB
instead
> > of
> > > > > a Fastman. I don't know what the differences are but I know
there's
> > no
> > > > > vibration. The only time I've ever had a vibration problem was
one
> of
> > > > > my headers being too close to the transmission case.
> > > > >
> > > > > Ron
> > > > > 00 PB SLT QC 4X2 5.9 46RE 3.92 LSD
> > > > > For modifications see my DML Profile (URL follows)
> > > > > http://www.twistedbits.net/WWWProfile/dakota/Kw9pV1EkFeOYY
> > > > >
> > > > >
> > > > > -----Original Message-----
> > > > > From: owner-dakota-truck@dakota-truck.net
> > > > > [mailto:owner-dakota-truck@dakota-truck.net]On Behalf Of crm
> > > > > Sent: Tuesday, July 02, 2002 11:38 AM
> > > > > To: dakota-truck@dakota-truck.net
> > > > > Subject: DML: Help!! Get rid of the Z-tube??
> > > > >
> > > > >
> > > > >
> > > > > hey guys, i have quite a quandry on my hands. i am having the gas
> > pedal
> > > > > vibration problem that some seem to get after installing an intake
> and
> > > > > new/ported TB. it's serious enough to where i know it should be
> fixed,
> > > > > but i am not sure how i wanna fix it.
> > > > >
> > > > > i feel fairly confident that the problem can be resolved by going
> back
> > > > > to the stock airhat that has the resonator on it, but that would
> mean
> > > > > getitng rid of my Z-tube. the dyno doesnt lie, and i know it
helped
> > out
> > > > > in the power. but, i know i want to keep the Fastman TB, so that
> means
> > > > > finding a fix somewhere else.
> > > > >
> > > > > Dan (the Fastman) suggested putting a little piece of sheet metal
in
> > the
> > > > > Z-tube perpendicular to the TB butterfly to help create some
> > turbulence
> > > > > and help cancel/dampen the harmonics to where the vibration
lessens.
> > > > > however, he said he cant guarantee that it would completely
resolve
> > the
> > > > > vibration. his idea was similar to what Bernd posted a while back.
> > > > >
> > > > > my other options would be to send back the Z-tube and exchange it
> for
> > a
> > > > > Stage II. or, i could go back to the stock setup with a drop-in
K&N,
> > > > > minus that oddly directed airhorn and a larger opening in the
front
> of
> > > > > the airbox.
> > > > >
> > > > > so help me out PLZ! i wanna make the best decision that will
produce
> > the
> > > > > most power while at the same time getting rid of the vibration. i
> only
> > > > > have a couple days left to my 30 days on the Z-tube and i'm
> definitely
> > > > > keeping the TB. any help would be greatly appreciated.
> > > > >
> > > > > -adam
> > > > >
> > > > >
> > > > >
> > > > >
> > >
>
>
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:05:00 EDT