(on my ls2 gto) im running a 102 throttle body, 102 intake, and ls7 blade style maf fabbed into a australian over the radiator intake. I havent been to the dyno yet, but a friends car picked up 20whp with this intake and switching the maf's. Perhaps its got something to do with the huge cam im running or the combo of parts, but the price i paid for the maf as compared to one of those overpriced 92mm or 100mm maf housings is insane.
I really dont know about how much air you would need to move on a 5.3 though, i mean i am a 364 with literally every single bolt on made for the ls2 aside from power adders..well when the ARM switch is off

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