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Hi all,

Just wondering if anyone can shead any light on my thoughts about upgrading the standard injectores in my 1996 gtst skyline..

i'v been reading a lil on the power ppl are making with mods they hav done to acheive the power.. im after a responsive 250 or so rwkw..

Now i'm thinking i deffinatly have to upgrade the injector's in order to acheive that sort of pwr, yet in sum threads i read from others, they are saying they have, bla, bla, bla, also with an after market fule reg.. and no after market injectores..??

So my question "is it possible to make 250rwkw Safely with a fule reg and no aftermarket injectors" .. ??

Cheers guys..!

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Hi all,

Just wondering if anyone can shead any light on my thoughts about upgrading the standard injectores in my 1996 gtst skyline..

i'v been reading a lil on the power ppl are making with mods they hav done to acheive the power.. im after a responsive 250 or so rwkw..

Now i'm thinking i deffinatly have to upgrade the injector's in order to acheive that sort of pwr, yet in sum threads i read from others, they are saying they have, bla, bla, bla, also with an after market fule reg.. and no after market injectores..??

So my question "is it possible to make 250rwkw Safely with a fule reg and no aftermarket injectors" .. ??

Cheers guys..!

No

If you wana upgrade your car do it properly or dont do it, think about it not only are you now pushing the car over the standard power but do you really want to be doing that pushing standard parts that far and knowing failure can lead to a engine gone. Just get a set of nismo 555 for that power or if you want to save I guess you could atleast hi flow your stock ones.

Indeed stock 370cc injectors SHOULD make 300rwhp if you have everything "right" (nice tune, good fuel pump, efficient engine setup). But then again, that's not 250rwkw, it's 224rwkw.

Get some bigger injectors. Also, your injectors are getting old now anyway and are probably half full of gunk. Get new ones (or at least cleaned and flow checked S15 445cc ones). Add new o-rings and you will have another 20% head room. I'd suggest 550cc though if you bother. a couple of hundred extra (compared to S15 inj) spent properly now will be worth it in a year or 2

Edited by simpletool

the general rule is that:

< ~230rwkw stock injectors/fuel pump/afm will manage (ecu is still needed for decent power)

> ~230rwkw bigger or highflowed injectors/aftermarket fuel pump/z32afm/ecu are required

knowing what i know now... if i had a fresh gtst, i'd probably buy a second hand gcg highflow, second hand pfc, max out all the stock injectors/afm & throw monies at suspension and handling. more power can always be purchased later if you want/need it

the general rule is that:

< ~230rwkw stock injectors/fuel pump/afm will manage (ecu is still needed for decent power)

> ~230rwkw bigger or highflowed injectors/aftermarket fuel pump/z32afm/ecu are required

knowing what i know now... if i had a fresh gtst, i'd probably buy a second hand gcg highflow, second hand pfc, max out all the stock injectors/afm & throw monies at suspension and handling. more power can always be purchased later if you want/need it

So you would prefer 230rwkw compared to your current 320rwkw? Yeah right :D

if you had the injectors prefessionally cleaned first to make sure they are actually flowing 100%, you could probably nudge 250kw on them without touching fuel pressure too much, but it isn't advisable.

Rolls, he couldn't use GTR injectors as r33 rb25 ones are side feed not top feed like rb26 ones. he could use s15 injectors though.

Rolls, he couldn't use GTR injectors as r33 rb25 ones are side feed not top feed like rb26 ones. he could use s15 injectors though.

A custom fuel rail is pretty cheap, that's what I did.

Edited by Rolls

Well guy's appreciated the help!

Yea i think ill just by a second hand set of injectors of sumone that fit straight in and be done with it :down:

i already hav a fmic, full exhaust, pod, gcg hi-flow turbo..

soo i just hav to get the injectores, fule pump, z32 afm, and a re-map and we should be happy :)

Cheers..

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