I have a 720/1600 injector combo that I used on my turbo setup-with a haltech could I continue to use those on a NA as long the tune is proper, or is it just way too much fuel?

 

they are overkill for an normally aspirated engine or any port configuration, but if your Haltech was able to yield pulsewidths for pre-boost drivability and off-boost cruising, then i don't see why you couldn't use them with a good re-tune.

that said, if it were me, i'd just get some stock injectors, clean/rebuild them and use those. there's no rush and you can get them pretty cheap with some time spent looking.

 

680 & 720

 

We just had a half bridge 4 port 13B N/A on the dyno that used 100% duty cycle on the primaries up to 5000rpm then used 100% duty cycle on the secondaries at 7500rpm.
He was using 460 primaries and 550 secondaries.

So I guess it depends on the motors porting!