So I get into my car today and go for a drive and I notice its not running like it usually does, its rough and dosnt feel right. So I give it gas and when it gets to around 4k it desides to backfire and basically die itself out. So I check the plugs, there fine, I check the wires, they are new, then I get to thinking mabye the powervalve on the carb went, so I changed that out. Thought the secondaries wernt opening, checked diafram, thats fine. I then thought the carb was ****ing up, so I took it apart and it was fine. Being pissed off I went and bought antoher carb thinking mine had just taken a ****, and I didnt want to re build it because I couldnt get the stuff until monday. So I buy the same carb I had (670 street avenger, vacc secondaries, elec. choke) I hook it up, adjust it, and it still does it. there arnt any vaccum leaks, so anyone have any idea? I am thinking check the destributors cap and rotor, the module, etc? I am running GM Hei with a tune up kit. the motor is a ZZ4 crate engine with mods. I havnt sprayed it in a while, but what is weird is it ran fine the night before... so I dunno. Any help is appreciated. I am quite pissed...
-Steve

 

i know this sounds stupid but maybe the fuel pump and/or filter? is it especially at WOT? cause my fathers car had the same symtpons you are mentioning and we thought it was something serious turns out to be a bad fuel filter and pump, everything went back to normal after we replaced, good luck man