S2 Rs4 S Injectors

[silva33]

Hey all,

Do anyone know the size of the standard RS4 S injectors. I am currently running approx 190rwkw with a pfc, trust front mount, full exhaust and 12.5psi

However I am getting injector duty cycles of up to 98%

I have just replaced the fuel pump however was told that the standard pump was working fine ( I replaced it really for future mods) which made no difference.

Are the stagea injectors smaller than others? I was under the impression that the stock turbo would not max out the standard injectors, and it was only until you replaced the turbo that the injectors needed upgrading.

Cheers

Dave

[darrinspencer]

You are getting close to max out the injectors. you could get a bit more out of them with a adjustable fuel reg.

At 98% the is no room for error. I would think with prolonged use your engine would have a short life.

The injectors in the neo are 350-370cc, cannot remember, I think they are slightly less than R33 370cc. Quick fix, turn the boost down, short term fix fit fuel reg, long term bigger injectors. I am getting at the moment 185awkw (249hp) with larger turbo, cams and blitz 525cc injectors with approx 68% duty cycle an a very safe tune.

[silva33]

Cheers, I think ill turn down the boost a tad. I have more mods to come soon including a larger turbo and injectors Z32 etc.

Im not going to install a FPR because of the future mods, if I was going to leave the car as it is then I would have one installed.

What sort of turbo are you running and at what boost?

[darrinspencer]

What sort of turbo are you running and at what boost?

Apexi ax53b70-p25 380ps

Tomie type b 260 deg cams

Boost set at 15psi, but not holding to redline, drops back to 12.5. Need to get this sorted and run 17-18psi and a bit more timing. Runs approx 11.7:1 AFR. Tuner was worried about pushing the neo too much.

Eventually the turbo will run out of puff, so maybe upgrade to a GTRs

[silva33]

Im going for the GTRS, at about 18psi. I hear a few people are worried about pushing the neo motor, are they really that much to worry about?

You car must go quiet well! Im quite happy with mine with the stock turbo at its limits.

[Tangles]

IF you ever do sell the Apexi turbo, let me know

how are you going about fixing the boost drop? mine drops from 16 to 13psi, hopefully the hks actuator fixes it.

[darrinspencer]

IF you ever do sell the Apexi turbo, let me know

how are you going about fixing the boost drop? mine drops from 16 to 13psi, hopefully the hks actuator fixes it.

Some people on the forum, very limited amount with the apexi are getting around 250rwkw on R33 25's with full mods.

Tuner thinks it is the actuator not holding, so I have been chasing another from another member that blew his turbo running 25psi. They actually have a ceremic exhaust wheel supposedly, but are way stronger than the factory nissan wheels.

It does pull well from 3500rpm. The apexi's are reportedly to have good midrange and the cams help out well

I was hoping to get to the track to see what it would do, but it keeps raining. That is is where the true performance is shown, not by a dyno result.

[silva33]

I saw your dyno sheet, and it looks like you have a lot of boost drop off up top which if correct will see a large power gain.

[darrinspencer]

I saw your dyno sheet, and it looks like you have a lot of boost drop off up top which if correct will see a large power gain.

The tuner spent over an hour playing around and adjusting the boost controller and the actuator, but could not get it right. So hopefully when sorted there will be an extra 20-40kw.

[Tangles]

DEATSCHWERKS injectors look the shitz

the ones I got delivered this week are high-flowed 480 to 550cc items

Im sure they would be able to do top feed.

they are in the States, email and ask for david or mike and say Brendan from South Australia referred you.

[darrinspencer]

DEATSCHWERKS injectors look the shitz

the ones I got delivered this week are high-flowed 480 to 550cc items

Im sure they would be able to do top feed.

they are in the States, email and ask for david or mike and say Brendan from South Australia referred you.

I would suggest the Blitz 525cc over the Deatschwerks, as the blitz are new and the same price delievered from greenline and are not reco highflow's. Just my opion.

[Tangles]

for sure

I went based on price - and factored in the fact that Im only after 20 more a/rwkw anyway.

they charged me bugger all, around $400 all up (they stuffed up, I wanted custom 450cc items they said have 550cc no extra)

[silva33]

I think ill be going for the denso injectors, I have used them in the past and have been great, I guess the benefits of having a neo though is that the injectors are cheaper! So i wouldnt go with the hiflow units.

[wolverine]

the neo injectors are 370cc

nismo 480cc are worth looking at if you are upgrading.

Edited February 14, 2008 by wolverine

[silva33]

I think ill leave t up to my tuner, I have previously used ~560cc denso injectors in an R33 which were fine for my application. Im building the car for the GTRS at approx 18psi however want a little room to move if I decide to go a bigger turbo again later on down the track.