Big thanks to all

Len Sabatine sabatine at epix.net
Mon Dec 4 14:01:59 GMT 2000


><snip>   Basically, I am
>building a plan of attack for reassembly and tuning.  So far, this is my
>plan .... (chime in if you see something that you could comment on) ....
>
>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.

>    Easy , try a 195 d stat

>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.

   Try Autolite Platinums @ .040 gap

>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.
>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.
>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.
>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.

    Try 36d total spark WOT.


>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.

>Hurt engines can look wet , so can those that run too cold and too rich. 
>.. Len



>Tim

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