Well, I have heard rumors of this being true. My stock JDM B16a1 VTEC Solenoid, has seemed kind of laggy, not nice and poppy and crisp, also you can't hear it like you can on other cars. I am going to replace the solenoid, but I have heard to replace it with the GSR Solenoid, becuase the solenoid is bigger and it pushes more oil into the rocker shaft and makes VTEC "POP" harder. What I mean when I say pop is the initial crossover when the car hits VTEC. I have ridden in a car with a B16a, B18C, and their cars seem to hit VTEC harder, than mine does. I have cleaned the Screen and it helped a little, but I would like to know if this GSR Solenoid rumor is fact or fiction.

NOTE: I replaced the Oil Pump on the car yesterday and the car rides a whole lot better, and hits VTEC a little harder, the only thing is it seems that it isn't hitting hard enough.

 

The B18C is a higher displacement engine with a more aggressive cam, of course it will pull harder at VTEC engagement. As for "popping," I'm not sure what you are talking about. The crossover should be fairly smooth on either engine unless something is wrong.

The B16* and B18C* VTEC solenoids are interchangable and should be identical, only one with a Honda P/N, the other with an Acura P/N.