@buttondoor posted:@jffr, I'm using a Victor Jr. intake. My FAST EZ TBI had 4 injectors. 1 O2 sensor (as you know, there's basically only 1 spot per side to accomplish upward angle and easy access, so it was basically where yours are). 636 bhp was within the limit for the FAST EZ per its manual (we set the fuel pressure regulator accordingly by their manual). I also called FAST (Edelbrock) several times in the process and was given some interesting suggestions, some of which were contrary to the manual and the logical startup wizard and TPS reset procedure, etc., but nothing was really solving it, and it was out of warranty by the time we put it in the car, and I had already had "successful" Pantera FAST users (not EZ versions) spend considerable time with it, also unsuccessfully if for no other reason than fouled O2 sensor, so after a few more resets on new O2 and plugs, I bailed on it. Tuning was initially done on a dyno, but that was of course without my exhaust, etc., and that shop was over 5 hours from me at the time.
The FAST XFI 2.05 system is port injected. I have an injector for each cylinder, which was made easy because the 3V CHI manifold already had the castings for the injectors. CHI is one of the few companies that offers an intake manifold for a 9.2 deck Fontana aluminum block. When I decided to go from batch fired injection to sequential it was quite easy because FAST offered a dual sync distributor which allows the ECU to control the timing. When I switched to sequential port injection the car ran even better than it had when it was in batch fired. The gas mileage also went up by about two mpg, not that I was doing it for economy. The big problem with FAST is that when they were bought out by Comp Cams, the upgrades to their systems stopped. I think the last time that their software for the XFI systems was upgraded was in 2014. Not sure about how their tech support works these days because I haven't called them in years. There is a man in California that has a website called Fast Man EFI. He is an expert on the FAST systems along with other aftermarket fuel injection products. I have quite a few miles on this car with the fuel injection system. When we had the POCA rally in Monterey California, I drove the Pantera straight through back to my home in Arizona. It was a 1100-mile drive through numerous altitude and temperature changes and the EFI system performed just like it does on a modern car.