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Re: Scott's Setup

> Cory Erickson wrote:
> > Well, with the Merkur computer, I can see where a good intercooler and
> > lots of boost might run Scott on the lean side...
> Why's that?  I thought all the non-IC computers ran very rich (~10:1@WOT).
> Now once he reaches 100% duty cycle, he might go very lean after that ;-).
> He shouldn't hit that point until he's making another 50hp or so...

I _think_ it's the other way around. I think the non-IC systems run leaner
than the IC systems (because of the added fuel needed for the denser air).
I know if I took off my IC and put in a pipe it would run richer than
sh*t. As far as the duty cycle is concerned: I guess that was my question.
The system is speed density with no boost sensor. From what I have been
told, the system runs a particular duty cycle based on how fast the VAF
opens/TPS/ACT/ECT. Since the only things that are really affected by
modifications are the ACT and VAF opening rates, is the computer "smart"
enough to open up the duty cycle after a while to hit the 100%, or what? I
know the computer runs things way on the rich side, but are the injectors
running at 100% at WOT/high_rpm/open_VAF all the time, even on a stocker?

Help, Joe!!!

> > Just having the "big"
> > vane on there probably would make it run even leaner (Joe/Scott might want
> > to check me on this) since the spring is tighter and the voltage
> > boundaries are the same (0-5 V).
> I can see how the big meter could make him leaner if he's getting twice
> the airflow at a given opening angle than the small meter, and the voltage
> versus vane angle ratio is the same on both meters.

The voltage vs. vane angle is the same on both, but the spring on the
TC/SVO one is much tighter. I have never put a big VAF on a small VAF car,
but I assume it would run a little on the lean side until you messed with
the spring (with after Joe's continual advise I have learned to stop
doing). I would assume most of the difference between the meters is seen
in the algorithm in the computer.