Don't run a maf calibrated for 30's with 19# inj. It will run like crap. If you're doing the gt40/e cam swap and don't plan on boosting,n2o,etc. I recommend either getting a new maf with 24# inj or running the 30# setup with a chip. The 19's are border line too small. 24's are ideal. Don't forget if you haven't done it yet throw a bigger fuel pump in with that swap(if it's still stock)