About 2 years ago, someone on a forum posted some strong complaints about the ProComp system. Their main complaint was that it was a Chinese casting and that it wasn't accurate, the ports didn't match, and the machine work wasn't good. They had to do a lot of machine work on it before they could bolt it up.
The problem I had with it was that the injectors were on the outside pointing inward toward a wall on the intake. Thus, whatever fine atomization you had from the injector is spoiled when it hits a wall. I went with the Borla 8-stack system because their injectors were on the inside of the throttles pointing outward and directly down the intake. There are some other systems on the market that do the same.
Even with a good casting and precise machining as I see with the Borla, when you have a variety of blocks, different heads with possibly different port configurations, you might have to do some port matching and adjustments to get the intake manifold to match the head. I had to use double intake gaskets to raise the intake manifold up slightly to match the ports. I also had to do some hand cleanup on the manifold and head.
I went with the Performance Electronics ECU. I have had several years experience with them (actually since they started in business) and their customer support is great. I haven't started my engine yet, but I am in the process of wiring everything up and will give a follow-up report after I am running.
-Bob Woods
Forum: Tornado GT40 in Texas
Introduce Yourself: Bob Woods in Texas