Boost Cut and Injector Size

[CSx8213x]

I would like to ask this 2 questions ....

R33 GTS with RB25DET engine .... this engine got boost cut or not ?

and .... what is the original stock injector size for this engine ?

 

[Innocente]

Boost cut is set by the ECU, not the engine. However in the stock setup, the R33 GTS has a standard "2 stage" boost. 5psi then 7psi max controlled by the stock actuator.

 

[CSx8213x]

ohh ... i mean if i using a boost controller ..... is there any boost cut from the stock ECU ?

 

[Innocente]

Yes. 1.0bar.

 

[CSx8213x]

thanks ..... bro Innocente ...

then how about the injector size ?

ermm... can i take away the boost cut without get any aftermarket boost cut defender like that ?

my friend told me RB20DET no boost cut ... is that information correct ?

 

[opp61]

thanks ..... bro Innocente ...

then how about the injector size ?

ermm... can i take away the boost cut without get any aftermarket boost cut defender like that ?

my friend told me RB20DET no boost cut ... is that information correct ?

Bud

The std ceramic turbine will be spitting out metal parts above 1 bar. Sure u wanna disable the boost cut? Unless u are going for a bigger turbine, leave the boost cut there. It is there for a reason.

 

[CSx8213x]

ohhh .... just want to know more of the car ...... collect more information before start the modification mah ...

 

[Innocente]

not sure about the injector size though

 

[a31gtst]

Side Feed 270cc

 

[CSx8213x]

a31gtst

the injector size so small only ?

 

[kaminari]

All std ECU mostly comes wth boost cut feature at 0.9bar....u can change to S15 stock injector 380cc for upgrading support arnd 400hp....

 

[CSx8213x]

thanks bro kaminari ....

just curious ... VR4 2000cc turbo using 450cc injector ... how come S15 2000cc turbo also ... just using 380cc ?

 

[kaminari]

myb tht`s the reason why SR20 is more fuel efficiency,hee.....Nissan n Mitsubishi...sure different.Fuel pump,fuel press....Ecu...all related

 

[a31gtst]

Its hard to compare like that, like kaminari said different manufacturer will have different specs.

If you want to try a cheap an easy upgrade for boost, go and get a RB20det actuator and replace your RB25 one. The standard 25 one is too soft, you should be running at abt 0.7-0.8 by just doing that if the rb20 actuator is still in good cond'tn. FYI I have run up to 1.2 bar of boost with a stock ecu before(vacuum hose tercabut!)...never faced any cut.

You can also source for S15 sr20 injectors and put them in, they are pnp.
Although you will need an engine management to actually support changes to the injector settings such as size and duty cycle else it wont work. Power FC is the way to go but hard to find for late model RB25det, there are other engine managements out there, just hv to see how deep your pockets are.

You can get other brands of injectors such as Sard or Nismo but very expensive especially side feed, its much easier and cheaper to find top feed injectors so if there is no need to upgrade the injectors jst yet then have fun first. Dont forget you must change your fuel pump and at least have a simple fuel regulator to check your fuel pressure.

 

[khoyos]

isnt it 370cc for RB25 and 480cc for S15?

 

[a31gtst]

isnt it 370cc for RB25 and 480cc for S15?

hahah... my bad. yes its 370cc High Impedance for RB25 and 480cc for S15 SR20.

270cc is actually RB20det injectors. Hows your ride dude, hope the monster's complete.

Cheers.

 

[khoyos]

my ride still not done yet la bro... the only progress is the dust on my car has doubled since i last visited the car in workshop. thats all...

 

[zephuros]

That depends on which RB25 it is from - R33/C34 or C35/WGC34/R34. And the standard S15 turbo injector is 448cc

 

[CSx8213x]

huh ... mine one it the late model of 33 gts ...
mean 370cc one ar ?

 

[CSx8213x]

bro a31gtst ...

the conclusion is the RB25det stock ecu no boost cut izzit ?
anyway ...thanks for your information and the suggestion .....

i got the information from Speedwork .. the APEXi stopped the production of the Power FC for R33GTS... mean i can't get a new unit from Japan ... only can try to get a used unit .....

but i prefer go for Microtech .. hehehe .... used this standalone before ... quite nice ... for the moment ... i just want to put in a piggyback and up boost it ... see how much power i can get with this little money spend ... heheheh ....