Big thanks to all

Bruce Plecan nacelp at bright.net
Mon Dec 4 04:18:05 GMT 2000


> 1) Go to a higher temp thermostat.  Currently running a 160.  Seems to me
> that I could benefit from higher temps without losing any performance.
> I am planning on a 180 deg thermostat.

Might get real nuts and usea 195d

> 2) Use a standard plug.  I'll be installing AC Delco plugs gapped at
0.040.
>  I have a supercoil and an MSD ignition system.

.030 to .035 (autolites have less erosive center electrode)

> 3) New heated O2 sensor.  If I am running rich then I believe the O2 must
> have something to do with it.  I am not (obviously) running around in OPEN
> loop all the time.  The car spends the majority of its time in closed loop
> so it seems to me that I must be running rich in closed loop also.  The
> fact that it appears I am running rich in ALL cylinders adds to this
theory.

Try the old one with the new combo, first

> 4) Up the fuel pressure and raise the injector constant.  Theoretically
> this should atomize the fuel more.  Any increase in atomization would have
> to be a benefit at this point (not in terms of performance ... but in
terms
> of not pooling fuel).  It may or may not help.  But, I cannot see it
hurting.

Why shorten the pumps (any injectors) life?.
You spraying at a closed valve usually anyway.

> 5) Decrease timing advance at WOT.  Was running a total of 42 degrees of
> advance at WOT.  If the Bosch +4 plugs are masking the flame then the new
> plugs won't need all of this advance.  Furthermore, given what I will be
> doing in number 6 below ... I can get away with less advance.  Probably
> start with 38 deg total advance and then work down from there.

Start at 30 and work up.
Least amount consistant with performance

> 6) Decrease fuel at WOT.  Probably start with an AFR of about 12.2 and
then
> slowly lean it out via checking the plugs and watching for knock.

Leave where you are get car running and see what the engine wants.

> That's pretty much it.  The only other concern that I have is why the
intake
> valves on my heads look wet.  If it was gas then it wouldn't be there
anymore.
>  Could be Oil ... but, I don't see the 'smoke at startup' symptom for bad
> valve seals.  If it matters ... I am running Positive control valve seals
> on the AFRs.

Make was just a cold engine?.
Remember the injectors aren't synch'd to the opening events so some fuel is
splattered around
Bruce
>
> Tim

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