I have a jdm b16 swap in my 93 si hatch. i have the basic bolt ons along with a port and polished head with a complete type r valvetrain, type r manifold and 65 mm tb. even on the highway at cruise speeds i still don't get the desired gas mileage i hear other hybrids are getting. i don't get on. if i'm lucky i'll get around 200 on a 11.9 gallon tank. what are ways with this engine with a ls tranny to get better gas mileage.

 

Running rich?

 

what ecu are you running?

 

yeah, thats way bad, i get 33ish with my b16a hatch and ive got a knock sensor CEL (not there)

 

jun chipped p28.

 

It could be your ecu or fuel management system.If it's not your ecu try upgrading the fuel system so you can get it tuned.

 

i just got a vafc II. if i get it tuned, will that help boost up the gas mileage.
please keep all the information coming i really appreciate the help.

 

If the car is running rich, you're using too much fuel... If you're running closer to stoich then you'll definately get better gas mileage