If this input helps I can add a good experience with adapting an aggressive cam profile with a 2.7 CIS system.
About 3 years ago I bought a pimped out 71` coupe that had a steel widebody kit on it. The car was a very cheap impulse buy. It had a freshly built 2.7 engine with R/S pistons(8.5 to 1) and stock 2.7 heads. The engine had the cleanest new looking Webers on it that Id ever seen. I decided to flip the car and keep the carbs.
I couldn't find a set of zeniths in ready to use condition and decided to install my old CIS system that I had kicking around from another project. I swapped in a fuel return line to the tank and high psi pump and gave it a go.
Well....... It worked great ! The S cams did have an effect below 1200 rpm but otherwise it ran better and possibly more powerful than the webers. Below 1200rpm it surged and eventually stalled from the excessive overlap but I adjusted the idle to about 1250 or so and unloaded the POS to a very happy new owner. As far as I know the car is still driven daily and has no problems.
Here is a before and after picture of that abortion.
After with CIS install
Kurt Williams