[Diy_efi] Intake manifold flow testing

[Grant Beaty]

I've always heard the monentum of the air (there is a lot of velocity going
thru the TB) causes it to not want to make a 90 degree turn into the first
cylinder, and instead builds up pressure at the rear of the manifold. Don't
know how true this is, its just what I've heard on other lists.

Grant Beaty

----- Original Message -----
From: "Geddes, Brian J" <brian.j.geddes at intel.com>
To: "List for general do-it-yourself EFI talk" <diy_efi at diy-efi.org>
Sent: Tuesday, February 11, 2003 6:35 PM
Subject: RE: [Diy_efi] Intake manifold flow testing


What I said below doesn't make any sense.  Ignore the "siphoning" comment.
What I've read suggests that the runners furthest from the throttle body
will get more air.  Don't know why - I'll have to do more reading.  :)

- Brian

>
> Hmm...using a water meter and a leaf blower is an interesting
> idea.  I think I'd need to have air flowing through all 6
> runners at once.  What I've read suggests that the runners at
> furthest from the throttle body will get more air, because
> the earlier runners 'siphon' off the pressure.  If all the
> other runners were blocked off, I might not see this effect.
>
> Maybe if I put an equal restriction at the end of each runner
> (fixed diameter nozzle, or something),  and fed the leaf
> blower into the throttle body, I could measure the pressure
> in each runner.
>
> - Brian
>
> >
> > There was a guy who did DIY flowtesting using various
> > adapters, a low pressure gauge, duct tape, and a leaf blower.
> > it may not be high-tech, but I guess it would be able to tell
> > you a little something about how well each intake runner flows...
> >
> > http://home.earthlink.net/~tmahon281/tech.html
> >
> > go down to about 2/3 to 3/4 of the way down the page, you'll
> > find the guy's info on it.
> >
> > -----Original Message-----
> > From: Geddes, Brian J [mailto:brian.j.geddes at intel.com]
> > Sent: Tuesday, February 11, 2003 3:43 PM
> > To: List for general do-it-yourself EFI talk
> > Subject: RE: [Diy_efi] Intake manifold flow testing
> >
> >
> > Is there a close enough correlation between EGT and A/F to
> > use EGT to estimate the relative airflow differences?  I
> > thought that the EGT-A/F connection wasn't very exact...but
> > I'm certainly no expert.
> >
> > - Brian
> >
> > > -----Original Message-----
> > > From: Dave Dahlgren [mailto:ddahlgren at snet.net]
> > > Sent: Tuesday, February 11, 2003 12:15 PM
> > > To: List for general do-it-yourself EFI talk
> > > Subject: Re: [Diy_efi] Intake manifold flow testing
> > >
> > >
> > > The sad part about this problem is that it most likely
> > > changes with rpm as well
> > > that is to say they can move around. a rich one at 4500 might
> > > be a lean one at
> > > 6000.  You could probably verify they stay the same by using
> > > some egt probes and
> > > data logging them along with rpm map and tps..Above all i
> > > think i would only
> > > want to add fuel.. Best idea is get a better intake manifold.
> > > Dave
> >
> > _______________________________________________
> > Diy_efi mailing list
> > Diy_efi at diy-efi.org
> > http://www.diy-efi.org/mailman/listinfo/diy_efi
> >
> > _______________________________________________
> > Diy_efi mailing list
> > Diy_efi at diy-efi.org
> > http://www.diy-efi.org/mailman/listinfo/diy_efi
> >
>
> _______________________________________________
> Diy_efi mailing list
> Diy_efi at diy-efi.org
> http://www.diy-efi.org/mailman/listinfo/diy_efi
>

_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://www.diy-efi.org/mailman/listinfo/diy_efi


_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://www.diy-efi.org/mailman/listinfo/diy_efi