Blowoff coming from an N/A KA24DE

[RB25-240sx]

That's the best way I can describe it. I recently had my head rebuilt (I'm an idiot and bent some valves) also replaced timing chain, gears and a few misc parts while I was in there. So, since I've put it all back together, when I reach about 5,500 to 6,000 RPM's and shift I hear something that sounds like a pressure relief valve. My only guess can be something to do with the EGR valve because I know it is bad. I also have a bad knock sensor but I don't think that would cause it.

[corn322]

Done anything to the PCV system? Ever replaced the valve? Only thing I can think of is the valve is gunked up and only opens when there is a lot of vacuum.

[RB25-240sx]

No, haven't replaced the valve, don't get smog checked here so I'm not gonna bother. Just put a new hose on the PCV when I did all this, haven't checked it but I'm pretty sure it's fine. This is gonna sound wierd because everyone that's listened to it said it sounded like some sort of pressure relief, but my A/C belt was squealing before I went to work today so of course I tightened it up, now I haven't heard the noise since. I've only tested it out twice though. I supposed I could have been mistaken and the belt was slipping when I closed the throttle hard because I only heard it when I let off the throttle anyway.

Sorry for all the words, lemme know if anyone has anymore suggestions and I'll keep testing it to see if it does it again. (not too much though, don't feel like rebuilding anything else right now )