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Re: Here is what happened to CIS v. EFI

If I want the resisitor based enrichment (@full throttle), what value
resistor might I have to use? What should I start out with as a baseline?
I'm looking for 2.3 bar just as a limit, just in case. I will run only 2.0
,but I would like to have a little margin for error. Would a variable
potentiometer do well?

*Steve                                       Sachelle Babbar
*'84  5ksT 1.6-2.0 bar                    <SBABBAR@IRIS.NYIT.EDU>
*Cockpit adjustable wastegate, AudiSport badge
*Disclaimer:"Any information contained herein is based purely on my own
*personal experience and may not necessarily reflect yours. Use caution as
*your results may vary from mine."

On Thu, 19 Mar 1998, Lawson, Dave wrote:

> Bruce
> >
> Still waiting to hear about the mods to CIS that makes EFI not so
> great...and yes, it did just stop:)
> >
> I will throw out some of what I know, at this point I haven't done any
> of these mods because fuel is not my limiter.
> * Change the WOT O2 freq valve duty cycle map in the ECU as David K.
> detailed. Excellent idea, more fuel just when you want/need it and will
> work up until the stock system margin is used up.
> * Mess with system and/or control pressures. Others have much more
> details on just getting the CIS system to work correctly, let alone
> tweeked for high performance/more fuel flow. Russ S. recently detailed
> how finicky these pressures are for getting his MC engine to work right.
> * Swap out injectors for a like fitment. On the ur-q, you can swap in
> some mercedes injectors which flow approx 20% more fuel across the
> board. Haven't dug into the 200 cross reference material.
> * Swap in a different shaped air funnel, narrower means higher lift for
> the disc which means more fuel. In the past Scott M. has talked about
> fuel flow relative to the disc arm movement using the monitoring
> potentiometer.
> * Swap in a different fuel distributor. CIS was fitted to many cars in
> the 70s and 80s, including audi, volvo, saab?, bmw, mb, porsche, vw, and
> maybe a few more.
> -
> Dave Lawson