1228746 TBI 305V8 stumble

[WEG1192 at aol.com]

In a message dated 9/28/2001 8:58:01 PM Eastern Daylight Time, 
jwvess00 at home.com writes:

> There is no vacuum to the CCC distributor, and no weights/springs.  On
>  Dad's '86 caprice, we used his CCC distributor in the TPI conversion.  I
>  forget why (probably one less unknown since they were both big-cap HEI).
>  Worked fine.  

ok, it sounds like the CCC distributor is the same as the later ECM 
controlled HEI distributors. If there are no weights, no vacuum can then it 
must be fully ECM controlled.

>  
>  As far as electronics go, I thought the only two HEI distributors GM had
>  were either mechanical/vacuum advance, or ECM-controlled.  Are there
>  different flavors of the ECM-controlled HEI (besides internal or external
>  coil)?

This may be true, but like my website shows, you can convert any older 
mechanical/vacuum advance HEI to a fully computer controlled HEI distributor 
from the instructions in my website. I learned this quite by curiosity, but 
any expert on this list will vouch for this approach.
>  
>  When we have the bypass wire disconnected (to set the timing) we can set
>  the timing wherever we want, within reason.  Plug the bypass wire in with
>  the base timing set to 0 and we see 12 degrees or so at the balancer.  I
>  haven't tried rev'ing the engine to verify the advance changes (next on the
>  list).  I assume this means the advance circuitry works? 
>  
unrelated to the above, but if the engine idles but surges, i.e. idle speed 
goes up and down, then the engine is running lean. I had this problem on my 
first system. If its rich enough to cause an unsteady idle, then it will 
probably have a trace of black smoke from the exhaust. One thing else you can 
do is pull the temp sensor connector, put a jumper on the connector, and 
drive the car. I have found that the engine will run richer with the temp 
sensor circuit shorted, so if this stops the hesitation, you were running 
lean. JW
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