Jump to content
SAU Community

Recommended Posts

it's time for me to upgrade my injectors, the factory ones are now at max flow. So what i am after is some first hand experience with aftermarket injectors... What's worked? What's failed? What should i steer clear of?

Current mods that you may need to know are:

T3/T4 turbo

PowerFC

Malpassi Fuel Reg

FMIC

running 15psi boost

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/
Share on other sites

it's time for me to upgrade my injectors, the factory ones are now at max flow. So what i am after is some first hand experience with aftermarket injectors... What's worked? What's failed? What should i steer clear of?

Current mods that you may need to know are:

T3/T4 turbo

PowerFC

Malpassi Fuel Reg

FMIC

running 15psi boost

I dropped in a set of nismo 555cc injectors into my car, and the Sard ones were cheaper but needed collars to fit, which took the price up to the same as the nismo ones!.....the nismo one drop straight in with no problems!....easy!

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2410303
Share on other sites

not only that the sards require a plug rewire. Nismos would be much better as they are a true drop in replacement. The only thing that i think they dont come with is new o rings, and its highly recomended to change them while their out so you dont get a leaky injector down the track.

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2410402
Share on other sites

because you dont need to control the fuel pressure with an aftermarket pump on, cause you have a/m management needed to control the injectors. Does that make sense. I think it does.

I kept mine on just for the ability to keep monitoring fuel pressure....im lazy though.

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2411090
Share on other sites

not only that the sards require a plug rewire. Nismos would be much better as they are a true drop in replacement. The only thing that i think they dont come with is new o rings, and its highly recomended to change them while their out so you dont get a leaky injector down the track.

what injectors are you using on your cars michael? i was think of going the Nismo 740cc injectors, talking with a few people, we think the 555cc wouldn't allow for enough future growth.

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2411529
Share on other sites

I dropped in a set of nismo 555cc injectors into my car, and the Sard ones were cheaper but needed collars to fit, which took the price up to the same as the nismo ones!.....the nismo one drop straight in with no problems!....easy!

i've also heard that the Sard injectors aren't the best nozzle

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2411538
Share on other sites

Shane in my r33 I have 550cc SARDS and in the race car we got 850cc SARDS. I think the basic equation is that its 1HP to every 1cc, so going on that 550hp @ the fly is the max, call it 500hp to be safe. Thats about 420hp @ the wheels.

I think the price difference is almost nothing for the 740cc nismo items, might as well go them if you think your going to come up short with the 555cc ones.

Whats the t3/t4 you have rated at? Unless your changing turbos in the future that will tell you how much you should allow for.

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2411927
Share on other sites

Hi Shane. I know it's a bit of topic, but could i ask at what power did the stockies run out at.

Im upgrading the turbo and just wondering what roughly the 370cc will do. :)

i had it tuned to 225rwkw, then we downtuned it to 215rwkw to try stop the pinging. they are still maxing out...

from my googling during the week, i found that 370cc is probably only good for 210rwkw.

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2413750
Share on other sites

As usual it's all in the numbers...................

210 rwkw + 65 rwkw for losses = 275 rwkw

27 rwkw x 1.34 = 368.5 bhp

Pretty close to 370 cc = 370 bhp.

550 cc = 550 bhp

550 bhp / 1.34 = 410 rwkw

410 rwkw – 65 rwkw losses = 345 rwkw

That’s at standard fuel pressure (34-36 psi)

You could use the adjustable FPR to raise the pressure to 47 psi and you are looking at just over 625 cc of flow

625 cc = 625 bhp

625 bhp / 1.34 = 466 rwkw

466 rwkw – 65 rwkw losses = 401 rwkw

47 psi fuel pressure + boost, say 25 psi = 72 psi

Which is well within the range of a Bosch fuel pump (044 for example).

I wouldn’t use a Walbro though. Plus I would STRONGLY suggest using new fuel hoses and clamps for that level of fuel pressure.

:O cheers :O

Edited by Sydneykid
Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2414871
Share on other sites

you didn't mention an upgraded fuel pump in your list of mods... have you looked at that?
Which is well within the range of a Bosch fuel pump (044 for example).

I wouldn’t use a Walbro though. Plus I would STRONGLY suggest using new fuel hoses and clamps for that level of fuel pressure.

:huh: cheers :)

i currently have a Walbro pump on, i'm on my 2nd one in under 12 months. the latest one has been on for 3 months and has already started to shit itself... a Bosch 040 will be going in ASAP.

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2415943
Share on other sites

go the nismo 740cc, they only work out to be $50 more (will it was in my case), that is like $8.30cent more pre injector :rolleyes:

what ECU are you running? someone mentioned to me that PowerFC doesn't really support big injectors all that well

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2416561
Share on other sites

Thats a lie...shoot whoever told you that :( If there is a problem its more then likely the tuner, remember a good tradesman never blames his tools.

And the powerfc in the race car is running the 850's perfectly fine :(

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2417143
Share on other sites

what ECU are you running? someone mentioned to me that PowerFC doesn't really support big injectors all that well

Thats pure bullshit dude :(

As stated, shoot the person that told you that :(

I ran 740's with a PowerFC, idle was as good as when the factory injectors were in there

Link to comment
https://www.sau.com.au/forums/topic/130304-fuel-injectors/#findComment-2417212
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • If as it's stalling, the fuel pressure rises, it's saying there's less vacuum in the intake manifold. This is pretty typical of an engine that is slowing down.   While typically is agree it sounds fuel related, it really sounds fuel/air mixture related. Since the whole system has been refurbished, including injectors, pump, etc, it's likely we've altered how well the system is delivering fuel. If someone before you has messed with the IACV because it needed fiddling with as the fuel system was dieing out, we need to readjust it back. Getting things back to factory spec everywhere, is what's going to help the entire system. So if it idles at 400rpm with no IACV, that needs raising. Getting factory air flow back to normal will help us get everything back in spec, and likely help chase down any other issues. Back on IACV, if the base idle (no IACV plugged in) is too far out, it's a lot harder for the ECU to control idle. The IACV duty cycle causes non linear variations in reality. When I've tuned the idle valves in the past, you need to keep it in a relatively narrow window on aftermarket ecus to stop them doing wild dances. It also means if your base idle is too low, the valve needs to open too much, and then the smallest % change ends up being a huge variation.
    • I guess one thing that might be wrong is the manifold pressure.  It is a constant -5.9 and never moves even under 100% throttle and load.  I would expect it to atleast go to 0 correct?  It's doing this with the OEM MAP as well as the ECU vacuum sensor. When trying to tune the base map under load the crosshairs only climb vertically with RPM, but always in the -5.9 column.
    • AHHHH gotchaa, I'll do that once I am home again. I tried doing the harness with the multimeter but it seems the car needed a jump, there was no power when it was in the "ON" position. Not sure if I should use car battery jump starter or if its because the stuff that has been disconnect the car just does send power.
    • As far as I can tell I have everything properly set in the Haltech software for engine size, injector data, all sensors seem to be reporting proper numbers.  If I change any injector details it doesnt run right.    Changing the base map is having the biggest change in response, im not sure how people are saying it doesnt really matter.  I'm guessing under normal conditions the ECU is able to self adjust and keep everything smooth.   Right now my best performance is happening by lowering the base map just enough to where the ECU us doing short term cut of about 45% to reach the target Lambda of 14.7.  That way when I start putting load on it still has high enough fuel map to not be so lean.  After 2500 rpm I raised the base map to what would be really rich at no load, but still helps with the lean spots on load.  I figure I don't have much reason to be above 2500rpm with no load.  When watching other videos it seems their target is reached much faster than mine.  Mine takes forever to adjust and reach the target. My next few days will be spent making sure timing is good, it was running fine before doing the ECU and DBW swap, but want to verify.  I'll also probably swap in the new injectors I bought as well as a walbro 255 pump.  
    • It would be different if the sealant hadn't started to peel up with gaps in the glue about ~6cm and bigger in some areas. I would much prefer not having to do the work take them off the car . However, the filler the owner put in the roof rack mount cavities has shrunk and begun to crack on the rail delete panels. I cant trust that to hold off moisture ingress especially where I live. Not only that but I have faded paint on as well as on either side of these panels, so they would need to come off to give the roofline a proper respray. My goal is to get in there and put a healthy amount of epoxy instead of panel filler/bog and potentially skin with carbon fiber. I have 2 spare rolls from an old motorcycle fairing project from a few years back and I think it'd be a nice touch on a black stag.  I've seen some threads where people replace their roof rack delete with a welded in sheet metal part. But has anyone re-worked the roof rails themselves? It seems like there is a lot of volume there to add in some threads and maybe a keyway for a quick(er) release roof rack system. Not afraid to mill something out if I have to. It would be cool to have a cross bar only setup. That way I can keep the sleek roofline that would accept a couple bolts to gain back that extra utility  3D print some snazzy covers to hide the threaded section to be thorough and keep things covered when not using the rack. 
×
×
  • Create New...