[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

Re: [T3] Injector interchangability?

----- Original Message ----- 
From: "Jim Adney" <jadney@vwtype3.org>

> > On 12/5/2003 Jim Adney wrote:
> > > Hmmm.... Would this also be the correct relationship between pressure
> > > across the intake venturi and airflow thru it?
> >
> > Yes. The relationship (Bernoulli's Equation if you're interested) holds
> > a venturi too.
> I had a chance to think about this a bit more over the weekend and finally
> realized that we don't really care how the pressure drop across the
> goes. It's still the pressure in the intake air distributor that is
feeding the
> cylinders, and that is what the PS is measuring.

I think you would still want to consider where in the air distributor that
the measurement is
being taken.At the "mouth" of the distibutor the velocity would be
greatest=high vac.Further in
,velocity would drop=lower vac.I believe that the port is centered where the
air takes the turn
 into the runners.Move the port rearward(back to the rear of the car)=richer
mixture and vice-

> So I still think an appropriate adjustment would be to increase the fuel
> pressure in proportion to the increase in displacement. This would be a
> approximation to the actual engne needs, which would be correct except for
> non-linearity in the pressure drop between the IAD and the cylinder.

Don't think there's a shoulder in there.Should be linear enough.

> the heads somewhat, should actually compensate for that latter effect


"....the whole world , Chico. And everything in it."

David V. Nelson
1969 Fastback FI (no matter what!)

List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]