I'm thinking about putting a set of 260 or 270 cc/min injectors in my J30A1. I have the V-AFC to tune the AF mixture. Has anyone done this? Pros? Cons? Expected power gain?

Any information regarding this is appreciated. Please no childish comments.

Thank you!!!

 

There is only two people on here that I know have upgraded their fuel injectors, however both of them were for an older motor/turbo application. I personally don't forsee your injectors as being the bottleneck of your system so I'm not sure if you will see much for gains at all and it may use a little more fuel. I am only speaking of my theoretical knowledge of the application not from actuall experience so I could be way off.

 

My machinist friend has a set of 260 cc/min injectors on a 98 civic EX and claims that they were the best power upgrade that he's done! ..... next to his 90 shot of nos (dry). I understand that in his case, the injectors help the nitrous system get enough fuel to mix with the N2O, but he claims that he has gotten gains in both modes (he did the injectors first).

I'm also thinking about getting the Comptech SC kit which says that new injectors are not necessary since they include the upgraded pump and regulator. I just think that having a larger injector could help improve the engine control by having a shorter duty cycle. The sizes that I'm looking at are +8% and +12.5% flow, so I don't think that the ECU would mind (& AF will be retuned via V-AFC).

SN, please ask the 2 people mentioned to comment on this & feel free to share your ideas as well!

Thanks!!!

 

Umm...not worth it unless you have some really extreme engine setup. And after reading your sig, you don't, so don't even bother.

 

Its just going to decrease the injector duty cycle, which I can tell you from looking at basemaps, is below 100% for all driving under the redline. The only thing youre going to do is spray more fuel. You dont need the excess fuel on your stock motor and all tuning the new injectors using a piggyback af controller is bring them back to stock af ratios by shortening the pulses. Basically pointless on a stock car.

 

So there won't be any power increase from the injectors even with the supercharger? Although the CT regulator is set up for the CT pump and stock injectors, I thought that there would be some potential for gains with tuning the fuel pressure to the larger injectors prior to the AF dyno/O2 tune.

Finch, can you please post a link to a typical basemap for my engine (J30A1)?

 

If you're talking with a supercharger that's different story.... You never mentioned that before.... From what I've heard the biggest gains for that motor is a new programable ECU which would help you out anyway. But with a supercharger and an air fuel managment system I think you will see some decent gains

 

Well, I know there is very limited support for Accords, and an even smaller amount for OBDII, and then close to none for V6 concerning chipping it, so if you added a supercharger you would probably have to get an AEM system of some sort or something. If you turbo/supercharge you need to spray more fuel than normal in, the stock injectors can't spray that much that fast and their duty cycle skyrockets to well over 100% Again, even after you supercharge you'd probably need something around 470 - 550cc injectors, a wideband o2 sensor for tuning, probably a walbro 255gph fuel pump, and then some. Without the supercharger, thats all gonna set you back over $1k without any fuel management systems and then stack the supercharger cost and labor on top of that.

If I still had Vista running on my MacBook I'd take some screenshots of my basemap and post them. Basically you have 5 tables, low cam fuel, high cam fuel, low cam spark, high cam spark, and injector duty cycles along with graphs to accompany them.

 

The supercharger kit that I'm looking at is the Comptech one ..... as far as I know, that is the only full setup that you can buy for my car. It includes an ECU, high pressure/volume fuel pump, fuel pressure regulator and colder plugs. It says that the stock injectors work well enough (due to the higher pressure). I think that new injectors and tuning could improve the output of the setup. The Apexi V-AFC that I have allows adjustment of V-TEC engagement and fuel maps for wide and narrow throttle (adjustable setpoint as well).

Sir Nasty: How would a stand alone ECU help? Is this by advancing the timing? What gains would be seen?

Finch: Can I get those maps read from my ODBII? If so what is needed?

 

Stand alone ECUs are always better, they change actual values instead of sensor voltages to trick the stock ecu into supplying more fuel. You won't find maps for your OBDII, almost guaranteed. I could barely find one for my OBDI 95