View Single Post
WERK I WERK I is offline
Forced Induction Junkie
WERK I's Avatar
Join Date: Jan 2003
Location: Wisconsin
Posts: 3,291
Originally Posted by Reanimotion View Post
..............................snipped for space..................

CIS with the eWUR is the most basic and therefore the crudest as we are altering control pressure only which means we are messing with air plate position and stroke.
- 100% stroke at a fixed 0.2bar differential pressure is 100% fuel delivery

CIS lambda with eWUR seems to be the best compromise of originality and control as we not only have the eWUR on Control Pressure but we also have full control of the Frequency valve which directly alters the differential pressure within the Fuel Distributor and therefore fuel delivery throughout the control piston stroke
100% stroke at a variable +/- ?bar differential pressure may be 120% or more fuel delivery with good control (fine and coarse)

CIS-E on the other hand has no WUR and operates on the same 0.2bar differential so theoretically for the same stroke and differential pressure should match the other two for flow - BUT the differential pressure regulator has a published normal range of +/- 1.6bar meaning the differential pressure can be massively altered and therefore may have a ceiling of 150% or more delivery at 100 percent stroke. And with excellent control authority including full fuel shutoff capability (overrun/Redline/safety/etc. Fuel Cut is possible)

Al this is ignoring limiting factors such as pumps and metering slits but in theory that's where I think the versions differ

Vehicles known to be running at present are
my 928 - on CIS-E using +/- 15mA of the 150mA range so 10% to achieve good AFRs

Dkubus Mercedes SLC V8 race car with insane CAMS using around 80kpa or +/- 0.8bar of control pressure to achieve idle and good AFRs to redline
Dkubus Mercedes SL V8 street car (stock) using around 30kpa or +/- 0.3bar of control pressure to achieve idle and good AFRs to redline

....................................snipped for space......................
Thank you very much for the explanation/update. Are the above V-8 Merc's on the Basic eWUR system? If they are, maybe you should rename the basic system to "CISe" or "eCIS or......

This ol' fart is getting confused.
'85 930 Factory Special Wishes Flachbau
Werk I Zuffenhausen 3.3l/330BHP Engine with Sonderwunsch Cams, FabSpeed Headers, Kokeln IC, Twin Plugged Electromotive Crankfire, Tial Wastegate(0.8 Bar), K27 Hybrid Turbo, Ruf Twin-tip Muffler, Fikse FM-5's 8&10x17, 8:41 R&P
Old 04-23-2015, 02:29 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #363 (permalink)