Re: What Air to fuel ratio should a 16v run . ?

[Mark Shaw <autox@inficad.com>]

XXSpArCoXx@aol.com wrote:

> That doesn't apply here  I haven't had a cat in my car since about 6
> months
> after I got the car. and I passed emmissions here in NY and in
> washington and
> in California, But the car running as lean as it is can explain why it
> past
> all those times.

That expalins how you probably got a reading like this from the
tailpipe.As a point of reference, the average emissions test used in
those states
(concentration at idle and/or low speed dyno) cannot find a missing
catalyst because the limits they use are way too high.  A good running
engine will meet 1.2% CO and 200 ppm HC without much trouble.
In states like Arizona with the IM240 test the total emissions in grams
per mile are measured and it is harder to pass without the properly
functioning
equipment.

> I'm not sure how much or what unit he tested it with , but considering
> the
> type of work and the cars he works on and the fact that the shop is at
> Ferrari
> Dealer ship in Greenwich CT he knows his stuff .

I guess I wonder about this, because you cannot "adjust" a closed-loop
systemand they all run 14.7 air-to-fuel ratio because that is the close
tolerance range
needed for the 3-way catalyst to work efficiently.  Anybody who has been

servicing cars built since the mid-80s should know this.

Also, don't discount the damage you will do to the O2 sensor which is
an integral part of the fuel system.  When these go sick you will not
only
get a truly rich or lean mixture, but you idle will be unstable.

> He Fiddled with the car for a while and got it to run 14.7:1 range
> barely but
> it still runs lean some time.  with the full throttle switch its
> running low
> 14's and sometimes high 13's but never an exact number everytime.

I have to agree with the other poster.  14.7 is NOT LEAN but the
idealair-fuel ratio for complete combustion.  If you are talking an
older
carbureated engine, they typically run them a little richer because of
the
poor mixture distribution causes lean cylinders.  But with multi-point
fuel injection this is not as big of a concern.

> Now the Question what fuel enrichment system should I run?
> I think Techtonics makes one and everyone knows of autotech or can I
> get one
> from someone else or just go to radioshack and build one .
>  Or  should I just rip my cis-e setup out and drop kick the bastard
> and get
> the euro set up?

Why are you so obsessed with making it run richer?  If you have not
increasedthe air flow capability of the engine (intake, throttle body,
header, exhaust, cam)
then you will just be pouring more fuel in and getting no noticeable
performance
improvement.  The 16V is a good flowing head, but it doesn't develop
as much more torque in the lower range than the standard 8V 2.0L.  The
better
high end breathing simply extends the torque (and therefore horsepower)
at the
higher revs.  Putting more fuel in will not help with the low end
problem so you
will be not notice much improvement.  If you want more "punch" I would
go
for a header.  That's more low end torque with no bad effects from your
fuel
system running rich.

As for going to the "euro" set up, are you talking multiple carbs?  If
so,
have you ever owned a car with carbs?  Been there, done that...never
again!

Mark



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