I have a 97 R. I have a DC JDM header and carsound cat with AEM CAI. I recently got my Edelbrock VictorX intake manifold installed with a VAFC. The car now runs like crap.

When I picked up the car the car seemed OK, I drove the car home (10 miles) and as soon as I hit the highway and got to 6K RPM it was like I het REV Limiter. The check engine light came on and it ran rough.

I had a friend of mine take a look at it and he adjusted a few things. The car now will rev past 6K RPM but it feels slower. Check engine light is off now. He told me I should have it DYNO Tuned by this guy he knows and if I had plans to do a cat back to have that done before tuning and I should invest in a Fuel pressure regulator as well as the VAFC 2.

What are the differences between a VAFC and VAFC2 ?

What king of HP gains will I be looking at after professional tuning with the mods mentioned?

any feedback and or suggestions are appreciated.