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Hi fellas,

I am planning on buying some new injectors shortly either:

1) Nismo 740cc - $1,379 - New

2) SARD 850cc - $600 - used

I just got a few questions:

1) Will the sard 850cc injectors be too big for my application? I have a RB30/25 setup with a GT35 0.82/ar, intending to push out somewhere around 370rwkw?

2) I know there been some debate about the spray pattern between nismo (4 hole) and sard (1 hole), will the 1 hole spray pattern affect my performance much compared to the nismo injectors?

3) Will the sard injectors be really rough on idle? Will I have to set idle somewhere around 1,100 rpm?

4) Has anyone got these injectors on there r33 and encountered problems?

Cheers

Unless you get injectors that are so big they won't idle well, there is no difference except the ability to make more hp. I don't think 850's are at that level. People who say you will have crappy gas milage, poor idle, or stumbling problems if your "only shooting for 300rwk's" with a GT30 but think if you have a T88, you will magically have good idle and mpg with the same injectors are retarded. If 1000cc's idle well on a 1000hp car, they will idle the same on your car.

Now as to whether or not the tomei/nismo injectors are a better name brand than sard, that's a whole different argument.

If your worried about spray pattern - just get the fuel pressure bumped a little for the SARD's ;)

Will make them as good as the twin spray SARD's from what i've been told.

Although 740's from nengun are 1080...

Add shipping... maybe what $1120...

So i think you should shop around some more mate.

Because i would clean/flow test 2nd hand injectors and by that time its getting closer to new pricing :)

Just my thoughts

mate i have the exact same turbo and injectors on an RB25 and they work fine. Idle is smooth (well smooth for my liking). Just make sure you get it tuned by someone who knows what they are doing and you will be sweet because I have seen the exact same setup with a dodgey tune and it was running really lumpy and rich even tho the big flames dumped out the exhaust are cool the car runs like shit.

I too would like to know if bigger isnt always better or vice versa, I was looking at Sard injector on just jap the other day and noticed the 550cc and 850cc are the same price $1299 for an RB25, as im chasing 250rwkw why wouldnt i go the 850cc for the same price??????

Heres the links:

http://justjap.com/store/product.php?produ...=310&page=1

http://justjap.com/store/product.php?produ...=310&page=1

I too would like to know if bigger isnt always better or vice versa, I was looking at Sard injector on just jap the other day and noticed the 550cc and 850cc are the same price $1299 for an RB25, as im chasing 250rwkw why wouldnt i go the 850cc for the same price??????

Heres the links:

http://justjap.com/store/product.php?produ...=310&page=1

http://justjap.com/store/product.php?produ...=310&page=1

it is always best to use the closest match (but safe say 80-85% duty) injectors as you can get a 'better' tune 'easier', now im not saying that 850's wont suit but smaller injectors at 250rwkw would be my personal choice.

it is always best to use the closest match (but safe say 80-85% duty) injectors as you can get a 'better' tune 'easier', now im not saying that 850's wont suit but smaller injectors at 250rwkw would be my personal choice.

nissan uses 440cc injectors on a GTR, which is twice as much flow as a stock GTR needs...

Why?

for starters, things like transients, accel pump, idle stabiliser, injector over-run (the switch points) and so forth all rely on minute injector adjustments the smaller the injectors the finer control over these parameters.... big injectors are fine and work well but if you dont need them your car is better off without them especially in a daily driver situation...

I understand the theoretical reasons behind wanting smaller injectors of you don't need bigger ones, but in practice, does anybody have idling issues or poor mpg with (good quality) 850cc injectors that can actaully be attributed to the injectors, no matter the hp goals of the car?

I have the Sard 1000cc single nozzles "fire hoses" in my sr with cams etc. Got them cos I always contemplated E85.

Slight lope when cold. When warmed up it idles like stock. Idles at 1000 rpm. Running 63% duty cycle on BP98 at full noise.....so they may be too small when I convert to E85

Edited by juggernaut1

There is so much more to injector selection than just simple 100% duty flow rates. What about spary patterns(delta and alpha angle), operating pressures, dynamic flow rates at small duty cycles and differing frequencies, flow differntials due to injector temperatures.

I know that Richard Aubet (Autronic) will not enough support the Sard 800cc side feed injectors due to its massive change in flow w.r.t temperature.

From what I've seen in tuning the std nissan ecu's (with their proper current controlled injector drivers) is that the nismo injectors are about the only injectors I would use.

Edited by rob82
There is so much more to injector selection than just simple 100% duty flow rates. What about spary patterns(delta and alpha angle), operating pressures, dynamic flow rates at small duty cycles and differing frequencies, flow differntials due to injector temperatures.

I know that Richard Aubet (Autronic) will not enough support the Sard 800cc side feed injectors due to its massive change in flow w.r.t temperature.

From what I've seen in tuning the std nissan ecu's (with their proper current controlled injector drivers) is that the nismo injectors are about the only injectors I would use.

So I should get the nismo 740's instead of the sard 850s if autronic (i.e, vipec - since it's been ripped off from autronic) cannot support sards?

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