I have been having a probleme with my carb backfiring when i floor it, or rev it WOT in park. I called barry grant tech support and he assured me that it was not the right power valve. So when i was taking the carb apart I found metal shavings in one of my boosters. I guess it was left there after reaming it. So i called barry grant tech again and he said this time that my 750 VS speed demon with downleg boosters is just to big for my engine. 350 bored .060 with ported and milled vortec heads. (flat milled .018) voodoo cam with 227/233 @ .050 with RPM air gap intake. I thought it being a vs carb would keep me for over carbing my car. Anyways, what do you guys think?

 

why are you revving it wot in park?

Also a 750 vs is not too big. You should look at the holley carb sticky and follow it exactly and then the carb will be close to perfect.

 

well i guess its not WOT but just reving the car. I was reving the car to see if i could watch the pump shot. I follow that. Thank you

 

check your cam color. sounds like you need more fuel.

 

Until you address that, nothing else much matters.

Debris in new BG carbs has been documented here. Take the thing completely apart, poke through every single passage, clean up what they didn't. This is a clear-cut case of good design being wasted by poor quality control. Sending it back and getting a different one isn't going to change anything, because it'll have the same problem (or at least the potential for it). The carb isn't horribly mis-sized, although it probably doesn't need to be that big. It just needs help.