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hey guys

just wondering what kinda power the standard rb26 injectors and airflow metres will handle im looking for 400rwhp i currently have hks gtss and a forged engine.

can i use rb25 afms if so what needs to be done to get them to work on the 26

and what cc injectors would i need?

cheers

stock injectors and afm ahould do around 280rwk before you come into too much trouble. I bought 540cc injectors for my car as i dont want a grenade setup :D

as for the afm's..., dont qoute me on this but i think the standard r32gtst afm's have the same plug as the rb26.

i read this somewhere a while ago. they are the same size as the gtr afms too, if this is the case they will do 400rwhp.

IIRC about 280awkw is the limit (someone will correct me). You can tune past the AFMs, and if you wanted to get a bit more out of the standard injectors you could raise the fuel pressure with an aftermarket regulator. Since you've spent the dough on the forged motor i wouldnt bother with the regulator hack and just go for a new set of injectors. To get changed AFMs and injectors to work you will need a tune. You might be able to get a PFC to limp to the shop if you select the new kit in the menus.

IIRC about 280awkw is the limit (someone will correct me). You can tune past the AFMs, and if you wanted to get a bit more out of the standard injectors you could raise the fuel pressure with an aftermarket regulator. Since you've spent the dough on the forged motor i wouldnt bother with the regulator hack and just go for a new set of injectors. To get changed AFMs and injectors to work you will need a tune. You might be able to get a PFC to limp to the shop if you select the new kit in the menus.

yep 287.4kw we made this at sau dyno day a few years back...de-screened afm's stock fuel pressure and injectors....stock turbo's etc

You should get close enough to 300.

Ferni has near on that power, stock AFM/Injectors.

If you want to push the turbos to the absolute limit, you'll need to upgrade both however

What is the injector duty and mixtures near 300? Stock fuel pressure?

If its running on the ragged edge then the OP could be well advised not to risk his shiny new motor. Ie stick to a safe 280, or add the goodies and run 320/330.

BTW Chicken at 200bar sounds delicious.

yep 287.4kw we made this at sau dyno day a few years back...de-screened afm's stock fuel pressure and injectors....stock turbo's etc

De - screened afm's. How much restriction do the screens pose? I have thought in pulling the rear screen off my nismo AFMS. Is it worth it? Would taking both screens off have any effect on how the AFM reads?

No need to descreen nismo afm's. They will meter just about anything you can give them. You can run stock motor, stock afm, stock fpr making 280kw atw with inj duty at 92 %. All in the tune.

De - screened afm's. How much restriction do the screens pose? I have thought in pulling the rear screen off my nismo AFMS. Is it worth it? Would taking both screens off have any effect on how the AFM reads?

AFM reads air mass so removing the screens will have no effect on the accuracy of the reading. The screens are just one of the many restrictions along the air path. I have no idea if removing them would make a measurable difference in power.

A mate who has WAY to much time on his hands worked it out (measured the size and length of the wire). The screens blocked 33% of the AFM he reckoned. Unfortunatley he never did a run with and without.

when but when air is being sucked past?

Huh? I

ts either the fact that ive just about finished a 12hr night shift or that makes no sense?

A screen both sides of the afm, restricting there air able to enter the afm. So you have an 80mm body with a 1/3 blocked by the screen.

god i need sleep.

De - screened afm's. How much restriction do the screens pose? I have thought in pulling the rear screen off my nismo AFMS. Is it worth it? Would taking both screens off have any effect on how the AFM reads?

6%

Huh? I

ts either the fact that ive just about finished a 12hr night shift or that makes no sense?

A screen both sides of the afm, restricting there air able to enter the afm. So you have an 80mm body with a 1/3 blocked by the screen.

god i need sleep.

its not like the air is just 'passing'

its being sucked in, the turbos, spinning, draw more air

So under load/induction, how much does it actually restrict....

Paulie says 6%, is it more/less/otherwise?

I have a RB26, and having issues at the momment can I post it here since were here? Also to this topic. I got my injector maxed out to nearly a 100% at 12 psi on stock turbos. got 209kw@7500 rpm (280hp) at rear wheels. and that wasn't spinning that hard, is a new engine can go to 9500 rpm with more $$$$!

To this new topic about MAF's, I was thinking of pulling the mesh off my sensors to clean them better. Alot of oil been through them. I have seen a DIY fix for these meters where U have to re-solder the filaments to the probe (I wouldn't advise anyone to doing this though). They are a sealed unit, with the time you waste, might as well just buy a new or good second hand one.

It wouldn't be a good idea to remove this mesh with a standard ECU would it? The voltages under throttle and none throttle be affected. Maybe not.

I have a RB26, and having issues at the momment can I post it here since were here? Also to this topic. I got my injector maxed out to nearly a 100% at 12 psi on stock turbos. got 209kw@7500 rpm (280hp) at rear wheels. and that wasn't spinning that hard, is a new engine can go to 9500 rpm with more $$$$!

To this new topic about MAF's, I was thinking of pulling the mesh off my sensors to clean them better. Alot of oil been through them. I have seen a DIY fix for these meters where U have to re-solder the filaments to the probe (I wouldn't advise anyone to doing this though). They are a sealed unit, with the time you waste, might as well just buy a new or good second hand one.

It wouldn't be a good idea to remove this mesh with a standard ECU would it? The voltages under throttle and none throttle be affected. Maybe not.

you do not solder the "filaments to the probe" as you put it....the dry joints you solder are located under the square cover.

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