I have had a similar problem on my 91. I put a JDM B16A in it and It does the same thing. It will only do it if I ease into the throttle in 1st or 2nd and even 3rd, or if I ease in after letting off the throttle at lower RPM. The only other things that could cause a slight hesatation would be a clog in the fuel system or if your timing was off. One of my friends at the Acura dealership said if I changed the wires and nothing happened to add a fuel pressure guage and see if there was any drop in fuel pressure when you are chaning gears or when you reaccelerate.