Analog Meter capability

[Shannen Durphey]

swagaero wrote:

> snip
> >
> > Tech 1A is convenient, but you don't know what you're missing.  You should see
> > MAP signals on a lab scope.  On a 4banger you can watch intake pressures
> > "bounce" when the valves close.  Just plain wild, to me.
> >
> > Shannen
>
> the problem is when you are trying to smooth out the signal from a lumpy
> disturbed cam I need to see the signal average and not the valves
> closing which is neeat to look at with my slow scopee.
>
> Steve
>
>                    ----|------||------|----
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>
> Well, okay.  On my 302Chev ( 214deg intake duration, 234 degrees exh @.050") the
> 83 Camaro ecm is so slow that even the "average" vacuum at idle isn't average.  I
> haven't tried installing a lumpy cam into anything newer to see what the average
> idle vacuum is, so I don't know what I'd see.  With my combo, I believe that the
> information is updated to the Tech1 even slower than it is collected from the MAP,
> so it would be difficult to use displayed info to map MAP.  There are other ECM's
> which do not update scan tools as fast as they collect information.  As far as
> watching the valves close, I find it interesting because the scope traces gave me
> a much more accurate "feel" for what goes on within the intake manifold than a
> vacuum gauge or Tech1 data stream.

Turbo City sells a MAP sensor which can be adjusted to compensate for a lumpy cam.
I don't know enough about electronics yet to build one, but I'd guess that you could
build something pretty easily.  Then, the effects of valve overlap could be negated
quite a bit.  Is that feasible?

Shannen