ox sensor on sequential efi,high overlap cam....

[Tom Sharpe]

Jemison Richard wrote:
<snip>

>         [Jemison Richard]  Turbos actually do care I believe.  Most turbo
> cams are wide center line, mild duration, moderate to high lift cams.  You
> don't want to lose all that pressure out the exhaust pipe!  Also, cylinder
> filling is largely taken care of my the pressure developed by the turbo.  So
> you don't need cylinder scavenging.  You already have a large pressure
> differential across the cylinder to remove combustion gases and recharge the
> cylinder.
>
>          Also,  grab your favorite cam grinders spec sheets or catalog and
> compare hot street and turbo cams and check me out on this.
>
>         Rick

Two points, Removing the combustion gasses is a problem with Turbo motors as the
exhaust pressure can be higher than the intake. They take a standard, mild cam
and crutch the exhaust by openning it sooner; more time to blow down. Net result
is wider CL.

You're right though, boost is better than lotts of cam and RPM, but a turbo at
high rpm will still need a big cam thou not as big as a na motor.

My point was (originally), that we should tune the idle by driveability and
'dead recon' the idle mixture from there and forget all that learning stuff (at
idle). Just use the O2 for a reference. That assumes that we can easily change
the map and have a good trimmer for the map sensor.

My 482 idled like a kitten with a Predator carb, alcohol, and roller cam..... it
just dribbled raw fuel out of the headers at idle, not enough to clean the
floor, but almost. (another sick try at humor).

later  Tom