Quad-4 (1228707 ECM) Rough Idle Problem

[nacelp]

They are talking about the old days of point ignitions, I beleive, and the
problem to a large degree was just firing the charge.  In a production car,
stock dissy, using points the successful ingition rate was like 92%, and
with all the advancements it's up to 98+% nowadays.
   Sure the bigger the cam the lousier the idle, but I'd venture a guess
they are really hinting at non streetable.
   I'd be most suspicious of your triggering some antistall part of the
code.  Where the ecm makes drastic changes, to prevent a stall at any cost.
Grumpy

> While surfing the net I located the following:
>   Very high overlap cams will exhibit an "eight stroking"
>   phenomena at idle where each cylinder will completely misfire
>   on every other compression stroke...  This phenonmenon is
>   responsible for the loping idle of the older hot-rod V-8s.
>   Unfortunately, with every other exhaust stroke pumping out
>   a cylinder full of unburned gas, hydrocarbon emissions soar.
>   The over-rich exhaust will not contain enough oxygen for the
>   catalytic converter to complete its breakdown of unburned
>   hydrocarbons, so even with the cat in place it will become
>   ineffective.
> The above explanation seem to perfectly describe the problem
> that I am having.  The exhaust is very rich, yet the catalytic
> converter is not all that hot (or glowing red, like it did
> years ago when I had an ignition coil go bad!).
> Therefore, it appears that the problem is likely caused by
> something in the top end.  When I checked the timing chain
> several weeks ago I verified that at TDC the camshaft alignment
> dowel pins went in easily.  As such, the only things left to
> check are the lifters and the cams.
> Any ideas?
> -Will


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