Bigger Injectors on sr20?

98se-rNOS · Aug 18th, 2003, 03:23 PM

I'm running a 98 200sx se-r with a 55 shot of nitrous. I've heard of people upgrading the stock injectors to 370cc. Does anyone know how much an upgrade like that might cost? I'm afraid if I do that I will have to send the ECU to jwt to reprogram which I know is not cheap...didn't know if it was worth it...here are the engine mods I have if that helps:

Custom CAI
Custom 2.25" Nakayama Exhaust
OBX 4-2-1 header
'96 G20 ECU
ZEX 55 shot nitrous

TheVodKA · Aug 18th, 2003, 03:26 PM

If you want to be safe, then you should definitely upgrade your fuel system in forced induction applications under nearly all circumstances. When you car takes the shot of NO2, the fuel pump, injectors and jwt reprog will make sure that your car doesn't run lean and blow the engine, which is the most common problem with guys who run NO2. The car's stock ecu and fuel system may be able to compensate for a 55 shot, but I wouldn't take my chance with it. Better to be safe than sorry.

nitestridar · Aug 18th, 2003, 09:27 PM

yeah better pump/injectors/fpr.... and you should be good

I am not to sure if you need JET to do the ecu for 370 injectors or if they will run on the stock ecu.

gottabfast · Aug 18th, 2003, 10:50 PM

JWT can make the 55 shot completely safe for you. They have a separate motherboard that takes over when you hit the swich. It allows the 55 shot only when full throttle and a certain RPM range is hit in addition to a timing map and injector pulsewidth. I you may as well put the injectors in and have them remap for injectors and possibly a 4-bar map instead of 3 bar of fuel pressure. That may not be necessary for a 55 shot. I think stock SR20s can take a 100 shot pretty easily. Make sure your motor mounts can handle the torque too. Having 370 injectors with a stock ECU will make your idle weird.

zeno · Aug 18th, 2003, 11:12 PM

You can pick up some used 370cc injectors for around $150-200. sr20deforums.com have them for sale all the time.

98se-rNOS · Aug 19th, 2003, 08:22 AM

I'm currently using ZEX which has a controller box which ratio's the NOS to Fuel and it cuts off if the ratio is incorrect so I think it's pretty safe running with that but a buddy of mine with a sunfire just put on some outrageously huge injectors (which made it idle like sh*t) but says now his car runs quicker without nos and a whole lot faster with his 85 shot spraying so that's where I got the idea...thanks for your inputs

fugiot · Aug 19th, 2003, 09:28 PM

If you can find a 91-96 300ZX TT at a junkyard, try to pull the injectors from that. The are the "official" Nissan 370cc's.