Fuel Injector question

[Iroc_g]

Ok, ive read quite a few injector threads, and it seems like people are pretty confident with the RC Engineering Injectors. I went to order some tonight, but ran into a problem. By every fuelinjector calibration i can find, i need an 850 injector to run at stock PSI and anywhere under 80% load on the injectors. (Every engine builder ive talked to says i should make about 400 - 420 hp at crank)

RC only offers a 750, and then a 1000. I really don't think i need the 1000, and im concerned that the 750 wont be enough. I dont plan any other power upgrades anyt time soon. But perhaps NOS or CRYo2 next spring.

The other thing is that im using the MAFT setup, and i was originally told that even on the stock computer, that would easily tune my setup. But i think i atleast need to get a socketed 95 and chip it for the Changed REV limiters and what not.

I guess i just need a little guidance at the end here getting the car completed

Thanks,
Greg

 

[liquordrunk]

Ok, ive read quite a few injector threads, and it seems like people are pretty confident with the RC Engineering Injectors. I went to order some tonight, but ran into a problem. By every fuelinjector calibration i can find, i need an 850 injector to run at stock PSI and anywhere under 80% load on the injectors. (Every engine builder ive talked to says i should make about 400 - 420 hp at crank)

RC only offers a 750, and then a 1000. I really don't think i need the 1000, and im concerned that the 750 wont be enough. I dont plan any other power upgrades anyt time soon. But perhaps NOS or CRYo2 next spring.

The other thing is that im using the MAFT setup, and i was originally told that even on the stock computer, that would easily tune my setup. But i think i atleast need to get a socketed 95 and chip it for the Changed REV limiters and what not.

I guess i just need a little guidance at the end here getting the car completed

Thanks,
Greg

I run Fuel Injector Clinic's 850's And 750's will be plenty for 400hp

 

[GSTBlack95]

Now I am not 100% but wouldnt 650cc's flip the bill as well for about 400 hp? This is off the top of my head correct me if I am wrong.

 

[liquordrunk]

Now I am not 100% but wouldnt 650cc's flip the bill as well for about 400 hp? This is off the top of my head correct me if I am wrong.

Of course.

 

[Iroc_g]

But, by going with all of the feul injection calculators... to run a .6 bsfc, and to not exceed 75% load, at 400hp, it says like 825cc or somthing.


I was kinda thinking that .6 is a little high for the fuel number though. I figured lke a .55 would be much better for everything. At that, a 750 might work well...

 

[daren_p]

But, by going with all of the feul injection calculators... to run a .6 bsfc, and to not exceed 75% load, at 400hp, it says like 825cc or somthing.


I was kinda thinking that .6 is a little high for the fuel number though. I figured lke a .55 would be much better for everything. At that, a 750 might work well...

I've tried those calculations before and they don't seem to work for me either, always ends up recommending injectors that are alot bigger then you need. For 420 hp 750's should be fine. I run FIC 750's and I'm making around 320-340 hp and I don't think I even hit 60% duty cycle, (can check some logs tonight to be sure). On the RC injectors, everyone says their 550's are great but when I went to buy injectors I had a few guys say that their larger 750's etc. weren't very good (I too was origionall going to get RC), that's why I went FIC & havent had any problems.