Re: 4KTQ Conversion Questions

[JShadzi@aol.com]

In a message dated 11/3/99 3:17:39 PM Eastern Standard Time, 
scottmo@teleport.com writes:

<< If your intention was to just use the CIS-E fuel distributor, air flow
 meter, and NF non-turbo ignition system on the Turbo conversion. Many have
 tried this approach, and many had engines that ran, but none ran very well
 IMHO, and they all had problems. I get emails from people who years later,
 are still trying to sort out these conversion projects.
    The CIS-E ignition system never expects the manifold pressure to be more
than 1.0 bar absolute, so its timing values will be way off under boost
conditions, and expecting the knock sensor system to compensate for the
knock developed during boost, is a poor way IMHO to run the engine.
Headgaskets don't like repeated detonation over long periods, neither does
the aluminum cylinder head, and the ring lands in the pistons.>>

    You mention that many have tried this and are still trying to sort it 
out.  My question is, are they attempting to run the turbo motor using the 
stock fuel system also?  
    The knocking that you refer to is likely more a function of a lean fuel 
mixture and not the knock sensor as you suggest.  Unless there is a provision 
for richening the fuel-mixture under boost, no knock sensor will be able to 
retard timing enough to compensate for the very hot, lean, detonation prone 
combusion environment.  It is an old trick to use a rich fuel mixture to 
lower combustion temps and prevent knocking.  I believe that a system with a 
provision to add equal amounts of fuel to each cylinder under boost 
conditions will work (using N/A CIS-III), and has the possibility to out 
perform the overboost limiting 5kt CIS system.  I am working on the BTDT 
right now...
Javad