The adventures with my 80 Quattro keep getting more fun! I initially acquired the car in the summer of 1999, the following spring I did a turbo conversion utilizing the stock CIS-3 fuel system and incorporated 5 EFI injectors piggybacked onto each intake runner for enrichment purposes, see a full write up here. Well, if you don't know this already, horsepower is seriously addictive, and the once unimaginable 230 hp or so just does not keep your fix for long. Running over 16 psi with the modified CIS turbo system, I still needed more!
My experience trying to tune the CIS system to keep up with high HP demands taught me that CIS systems, while extremely reliable and functional for normal or mildly tunes cars, in a 5 cylinder, if you want to really break the 250hp mark, you really start running out of options. CIS systems are extremely limited for two reasons: 1) Modifying them for increased performance is very difficult, and typically one must rely on a few experts world wide who have "cracked the code" and 2) The engine must ingest air through a restrictive airflow meter.
My biggest problem turned out to be that my airflow plate would top out around 14 psi, I could measure this via the potentiometer on the airflow plate. Any fuel needed a to run 14+psi had to come from my auxiliary system, and any air had to be supplied via increased vacuum.
Well, I had tricks up my sleeve, at a previous job at an Audi/VW tuning I had worked on developing a programmable EFI system for the 5-cylinder motor. I left the company, however, and subsequently development stopped too. But I continued on my own time, and recently successfully installed the system on my 80tq [4/2001]. Basically I am looking for 300-350hp, running a larger turbo at 20 psi I feel this is absolutely doable.
Please enjoy the documentation!
See me at my "best"-Special Agent DoubleOAudi investigating a local junkyard