[DeTomaso] efi horse power gain

[Kirby Schrader]

Well, what can I say...

It works to combine them. I can _prove_ it by measuring the manifold
pressure at the plenum on my car.

Why are companies like TWM using this technique if it doesn't/shouldn't work?

Either the explanation is wrong or the conclusion is wrong. Or both.

Let's not ignore the proven facts. If I did that in my job, I'd have
been fired decades ago.

Kirby

On Tue, Aug 11, 2009 at 2:59 PM, <JDeRyke at aol.com> wrote:
> In a message dated 8/11/09 8:02:16 AM, kirby.schrader at gmail.com writes:
>
> I have no idea how each cylinder's vacuum pulse can cancel out each other.
> That
> means one pulse would be negative (vacuum) and the other positive
> (pressure).....
>
> Correct- the strong pulses going back & forth thru an IR manifold are indeed
> positive and negative, as the pressure wave oscillates between the intake
> valve and the ram-tube top. As one intake opens and starts a negative wave
> downward, the preceding cylinder has just closed and starts a positive wave
> back out. I found the net from combining cylinders is zero. It's so
> prevalent that experts suggest using a fairly long piece of rubber tubing to
> connect a single intake port to a vacuum advance, so the rubber's normal
> pliability will dampen the pulses. Using metal lines is the worst- as I
> found. My vacuum with Webers wouldn't accumulate until I added a check valve
> like is in the power brake booster. But maybe the rules change with EFI-
> dunno; haven't tried it yet. FWIW- J Deryke