Re: Why would you have to MOD your CIS ?

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <43480d4.2518eaac@aol.com> JShadzi@aol.com writes:

>     I am not too familiar with that particular function of the MAC12D, but
> the point is that there are other functions within that system that enrich
> the fuel under boost which results in increased fuel pressure throught the
> injectors, which ensure proper fueling to each cylinder.  The cold-start
> valves are known for their poor distribution of fuel to each cylinder, and if
> used to enriched fuel under boost, can result in some cylinders being
> severely lean, while others are too rich-hardly a reliable device to prevent
> engine damage and ensure performance...

Yes, it twiddles the fuel frequency valve duty cycle.  Even this tops
out at about 220bhp, though.

Uneven fuel distribution is a _major_ problem in hard-driven MB engines,
with #4 and #5 running very lean at times.

--
 Phil Payne
 UK Audi quattro Owners Club
 Phone: 0385 302803   Fax: 0870 0883933