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how much rwkw can the jdm s15 480cc injectors handle?

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Just wondering, i know the jdm 6sp s15 have the larger 480cc injectors unlike the aust spec... does anyone know how much rwkw they can safely handle up to? I am thinking of doing the usual bigger turbo with 040 fuel pump, no more than 16psi boost, turbo back exh, intercooler, etc. I know you can get 230rwkw safely, but i am looking at around 250rwkw. Does anyone know the formula how to work it out?

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I wouldnt dream of pushing that with 480cc injectors.

Maybe if u upped the fue pressure beyond 4bar though.

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I would run a fuel regulator, not sure if that makes much difference, think it adds 10%

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im pretty sure s15 injectors start maxing out around the 230rwkws mark.

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im pretty sure s15 injectors start maxing out around the 230rwkws mark.

 

Ive managed to get 195.4 rwkw @ 13.6psi but the only problem we had was the AFM Flat lining at 5 volts.

 

get a z32 AFM and you'll hit the 200krkw mark EAAAAAAAASSSYYY

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jesus, S15 injectors start maxing out around 200kw maybe 210.

 

if you can't afford larger injectors, then your certainly can't afford the upkeep of a 250kw car.

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i wouldnt recommend pushing them any where over 200rwkw

 

they max out and if u push for to much power i can see u melting a piston

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keep it safe for f**k sakes what is wrong with you people 230pfftt

 

i wouldn't think of using s15 injectors passed 200 for saftey reasons, there is a difference between maxing out and maxing out, imo maxing out should be at 80% duty not 100% so dont even try.

If your hitting 80% on your injectors then you need bigger.

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im pretty sure s15 injectors start maxing out around the 230rwkws mark.

 

"start maxing out"?? lol

 

my tuner wouldn't push my S15 past 190 as it had stock injectors. one of the main reasons being safety.

 

he was able to get just under 200rwkw but pulled it back just to be safe as injectors were pretty much maxed out!

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If your tuners are tuning close to 100% duty with out your consent then there asking for trouble and so are you

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the injectors are fine, you've seen my graphs and A/R ratio before. Trent said they're safe so i took his word

 

i also told him i dont want to run the injectors over 80% duty cycle to which he replied that theyre safe...

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I have nismo 555's. I made a point of asking my tuner and he said they're fine for the 245rwkw my car makes, plenty of headroom.

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I used to know the formula but cant quite remember it all but my guess would be 650cc to be safe

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Ive always been told as Streetforced stated, tuning to 80% d/c for piece of mind...

 

Mine currently see's 100% d/c quite regularly, especially cold nights....it doesnt knock so im not too concerned but will go to 740s and a Z32 very shortly for piece of mind....and maybe a Disco.....

 

Off topic, is $950 a good price for a brand new Disco with S15 comp cover....?

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yes 950 is a very good price considering all garrett turbos underwent a price hike a few months ago now. must be old stock as there about 1300 wholesale now i think

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made 242kw on the s15 jap spec injectors :P that was at its limit. very aggresive track tune.

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Firstly S15 480cc Injectors came in all the manual Turbo S15's.

 

And Secondly I wish that they could flow enough fuel to make 242rwkws :o

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How do you know you have 480cc injectors? I was told mine were until i had them tested and they were 440cc.

When buying s15 injectors be careful as i believe most out there are 440cc not 480cc.

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How do you know you have 480cc injectors? I was told mine were until i had them tested and they were 440cc.

When buying s15 injectors be careful as i believe most out there are 440cc not 480cc.

 

ah see common mistake

s15 injectors are labelled as 480cc at 5bar but standard fuel rail pressure is actually 4bar so at a lower fuel pressure there actually only 440cc

if you ran your standard s13/s14 injectors at 5 bar they would also flow more than 370cc

 

there also got the brown/red/ terracotta colored tops on them as apposed to the purple top 370cc ones

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so you reckon 200rwkw is pushing it for stock s15 injectors

 

adm or jdm are the same?

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Yes mate, 200rwkw is more than pushing it unless my PwrFC is lying to me when it says 100% dc....anyone making more than this with standard fuel pressure is on a happy dyno or asking for trouble....

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Depending on your tune and boost they will vary slightly on injector duty cycle.

 

But hey there's only so much air the T28 will push and so much fuel the stock Injector are gunna squirt.

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no 200kw is safe

210-220 is pushing it

 

keep it safe

 

if your making just over 200 with your set up then thats fine

but if your chasing numbers like 220-230 then get bigger injectors its that simple

 

 

the way to calculate injector sizes is a simple equation

hp x BSFC(brake specific fuel consumption)

______________________________ = lbs/hr

 

number of injectors x duty cycle

 

then convert lbs/hr to cc/min which is 1cc/min = .0951lbs/hr

 

 

so if you where chasing say 300hp which is about 200kw at the wheels in most silvia range you would do

 

(300 x .50 = 150) / (4 x .8= 3.2) = 46.87lbs/hr

 

so 46.87/.0951 = 492cc/min thats on a 3 bar scale rail pressure so at 4 bar it will be about 425ccish

 

make sense?

 

if you wanted around 230kw then you do the same equation again but change the hp level, 230 at the wheels is about 250-260 at the crank so lets say 260kw which equals roughly 350hp

 

same equation but put 350 in instead of 300

 

(350 x .50 = 175) / (4 x .8= 3.2) = 54.68lbs/hr

 

so 54.68/.0951 = 574cc/min again down to a 4 bar scale will be around 500cc

 

now change a few things around on the 440cc , first off lets crank up duty cycle to say 95% and in the end we will raise the rail pressure to 5 bar with a fuel reg.

 

440cc at 5 bar is 480cc

480cc to lbs/hr = 45ish

 

45 x .95 / .50 = 85.5hp per injector

now multiply it by 4 injectors and you get 342hp

thats at the crank so convert it to kw 255kw and take off about 25kw from drivetrain and weight loss = 230kw

 

so in order to get 230kw from your s15 injectors you would need to run them at 95% duty and use a fuel reg and raise the rail pressure to 5 bar, and thats going to be leaving a 5% duty margin which you should leave around 20% so not very safe at all.

 

hope that sheds some light on the subject

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so its not the case that ADM are 440cc and JDM are 480cc? both same parts?

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yes both the same

manual s15's are 440cc at base rail pressure

automatic s15's are 370cc as base rail pressure

manual and auto s13 and s14's are 370 at base rail pressure

na are smaller but not sure on rates

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Hi,

 

I've got a similar question. After viewing most of these posts it looks like it's just about answered but I'll run through some of the mods I'd like to do.

 

If I'm to do up a stock JDM S15 Spec R manual, how much rwkw could I produce if I added these mods:

 

FMIC (can this be added with cold air induction for the engine too?)

Boost Controller (no more than 18 PSI, set to 10 PSI for daily driving I guess)

3" + Cat zorst (I heard you can run extractors via the turbo, is this ok, any risks?)

Z32 AFM

Power FC

ECU

740cc Injectors

Bosch 040 pump

Throttle Body upgrade (50-50, not a high priority)

 

Dynotune after all the mods @ 14 PSI.

 

I would like to aim for 225 rwkw @ 14 PSI?

 

Does this sound realistic, is there anything else I could bolt on or off?

 

I'm not comitting to doing any or much headwork, I just want a nice few touches and a decent gain of power wihout the HF's :).

 

 

Thanks.

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Hi,

 

I've got a similar question. After viewing most of these posts it looks like it's just about answered but I'll run through some of the mods I'd like to do.

 

If I'm to do up a stock JDM S15 Spec R manual, how much rwkw could I produce if I added these mods:

 

FMIC (can this be added with cold air induction for the engine too?)

Boost Controller (no more than 18 PSI, set to 10 PSI for daily driving I guess)

3" + Cat zorst (I heard you can run extractors via the turbo, is this ok, any risks?)

Z32 AFM

Power FC

ECU

740cc Injectors

Bosch 040 pump

Throttle Body upgrade (50-50, not a high priority)

 

Dynotune after all the mods @ 14 PSI.

 

I would like to aim for 225 rwkw @ 14 PSI?

 

Does this sound realistic, is there anything else I could bolt on or off?

 

I'm not comitting to doing any or much headwork, I just want a nice few touches and a decent gain of power wihout the HF's :).

 

 

Thanks.

 

It's good to see that you have done a search!

 

The stock T28/GT2560R typically runs out of puff a little bit before 225rwkw on an SR20. A Garrett GT2860RS (commonly referred to as a Disco Potato) would be a fantastic upgrade. Also factor in a decent tune.

 

Apart from that, everything else looks pretty good in that list. A throttle body upgrade isn't really mandatory unless your car is heavily modified.

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yeah s above your still going to be using a small frame turbo there is no need for a t/b upgrade.

and forget about aiming for numbers on certain boost levels, 225kw on 14psi would be a fairly big turbo like a 3071 or 3076 up

on a t28 14psi is going to get you much to 200kw, most of the gt series t28's need a good 16-18psi to start working right.

 

If you think you will be satisfied with 220kw then go to disco

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no 200kw is safe

210-220 is pushing it

 

keep it safe

 

if your making just over 200 with your set up then thats fine

but if your chasing numbers like 220-230 then get bigger injectors its that simple

 

 

the way to calculate injector sizes is a simple equation

hp x BSFC(brake specific fuel consumption)

______________________________ = lbs/hr

 

number of injectors x duty cycle

 

then convert lbs/hr to cc/min which is 1cc/min = .0951lbs/hr

 

 

so if you where chasing say 300hp which is about 200kw at the wheels in most silvia range you would do

 

(300 x .50 = 150) / (4 x .8= 3.2) = 46.87lbs/hr

 

so 46.87/.0951 = 492cc/min thats on a 3 bar scale rail pressure so at 4 bar it will be about 425ccish

 

make sense?

 

if you wanted around 230kw then you do the same equation again but change the hp level, 230 at the wheels is about 250-260 at the crank so lets say 260kw which equals roughly 350hp

 

same equation but put 350 in instead of 300

 

(350 x .50 = 175) / (4 x .8= 3.2) = 54.68lbs/hr

 

so 54.68/.0951 = 574cc/min again down to a 4 bar scale will be around 500cc

 

now change a few things around on the 440cc , first off lets crank up duty cycle to say 95% and in the end we will raise the rail pressure to 5 bar with a fuel reg.

 

440cc at 5 bar is 480cc

480cc to lbs/hr = 45ish

 

45 x .95 / .50 = 85.5hp per injector

now multiply it by 4 injectors and you get 342hp

thats at the crank so convert it to kw 255kw and take off about 25kw from drivetrain and weight loss = 230kw

 

so in order to get 230kw from your s15 injectors you would need to run them at 95% duty and use a fuel reg and raise the rail pressure to 5 bar, and thats going to be leaving a 5% duty margin which you should leave around 20% so not very safe at all.

 

hope that sheds some light on the subject

 

nice write up but but lost me half way through lol

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Hi,

 

I've got a similar question. After viewing most of these posts it looks like it's just about answered but I'll run through some of the mods I'd like to do.

 

If I'm to do up a stock JDM S15 Spec R manual, how much rwkw could I produce if I added these mods:

 

FMIC (can this be added with cold air induction for the engine too?)

Boost Controller (no more than 18 PSI, set to 10 PSI for daily driving I guess)

3" + Cat zorst (I heard you can run extractors via the turbo, is this ok, any risks?)

Z32 AFM

Power FC

ECU

740cc Injectors

Bosch 040 pump

Throttle Body upgrade (50-50, not a high priority)

 

Dynotune after all the mods @ 14 PSI.

 

I would like to aim for 225 rwkw @ 14 PSI?

 

Does this sound realistic, is there anything else I could bolt on or off?

 

I'm not comitting to doing any or much headwork, I just want a nice few touches and a decent gain of power wihout the HF's :) .

 

 

Thanks.

 

It's good to see that you have done a search!

 

The stock T28/GT2560R typically runs out of puff a little bit before 225rwkw on an SR20. A Garrett GT2860RS (commonly referred to as a Disco Potato) would be a fantastic upgrade. Also factor in a decent tune.

 

Apart from that, everything else looks pretty good in that list. A throttle body upgrade isn't really mandatory unless your car is heavily modified.

 

 

yeah s above your still going to be using a small frame turbo there is no need for a t/b upgrade.

and forget about aiming for numbers on certain boost levels, 225kw on 14psi would be a fairly big turbo like a 3071 or 3076 up

on a t28 14psi is going to get you much to 200kw, most of the gt series t28's need a good 16-18psi to start working right.

 

If you think you will be satisfied with 220kw then go to disco

 

Thanks for the info guys :). Gotta love search for sure. It's good to run it past some people who know what they are talking about before people like me go ahead and do something they shouldn't too.

 

The only query I have now is the chance of running the extractors via the turbo...I have seen this in a post a while ago but I haven't heard many people talk about extractors on a turbocharged setup. Is this due to the cost or concerns it can cause?

 

Is it recommended to use an oil catch can too?

 

That formula is pretty cool btw, I'll use it!

 

 

Regards

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