sequential efi on 440?

[Shannen Durphey]

Scott Shotton wrote:

> Mike Williams wrote:
> >
> > I'm building a chrysler 440 for in my 4x4 picup and would like to use
> > sequential efi. I sent mail to Electromotive and Felpro. Have'nt heard
> > from them yet. Right now I'm triing to decide on the cam. Called Comp
> > cams for advice, they said most mutiport efi makers don't recommend a
> > cam 220 degrees duration @0.050. Is this right and why?  P.S. Most of
> > the material in this group is over my head but I'm learning. Thanks to
> > you all...Mike
>

snip

> A cam with too much duration does not produce adiquate vacuum at idle.
> The MAP (manifold absolute pressure) sensor will read low vac. at Idle
> (thinking there is a load on the engine) and increase injector pulse
> width.  Basically dump fuel @ idle.
>

snip

One thing to consider is that roller cams can allow faster valve opening and
closing rates, thereby reducing overlap.  This can help to a point.  Also,
"turning up" the idle speed (in the chip) can help some if the cam's a
little too large. Neither of these will make a radical cam work. But...Mopar
440 might be very expensive engine to install roller lifters into.  You
might call Crane Cams, they kinda started the high performance computer cam
business.  Maybe they can come up with a grind for you using flat tappets.

Shannen