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hi all ,I baught these of a fellow well known sau member as Nismo 740cc for Rb25..

took my car to the tuners yesterday and even at 100% duty cycle the car was leaning out bad,

in fact on initial start up instead of running rich the a/f ratio went right to 18:+,

eventually at around 11pm we had had enough of trying to work out what was going on(had osc scope to get verification of inj duty)

today removed the injectors and tuner said he is certain they are not 740cc,but closer to 270,(are these na silvia jobs ?)

he was refering to the fact that they spray holes were smaller than the std 370 injector spray holes..

the numbers on the injectors are side:a46-00 other side:0f554922 have a jecs filter on them.but no jecs moulded in the plastic..

i want to confirm what they are b4 i approach the guy i got them from ...cheers..

post-43014-0-68480800-1326165487_thumb.jpg

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You don't say what ecu you have and whether it is set up for the different injectors. The 554 is Nismo code for 740cc. Maybe you have not got enough fuel supply and they are running at 100% duty cycle to try to compensate. But I'm no tuner.

hey ,thanks for the reply,my setup is :

Hks 2835 pro s

some huge bosch pump,tuner says its flows more than an 044 sorry dont have more info on on it..but he regularly uses this pump..

z32 ecu with type 2 nistune,

ebay spec fmic,

but i`m quite relieved that they are the 740 `s..

ok i removed the fuel rail and found that the new o rings (small ones) are squashed and in some cases split,

also the lil green spacer thing after the oring is squashed,the guy i had flow test them supplied new orings and pintle caps,

the caps were not the 4 pronged ones normally on these and told me i had to trim them flush with the end of the injectors,

when fitting them we they were hard to push in and didnt feel "right" to me,cap looked like then ends had been chewed off!

was told to just use the metal covers and pull them down buy doing them up this way.slowly and evenly..

there was no signs of leaking (we did check for them more than once)but surely this couldnt have been helping matters ?

Edited by Jamie72

hey ,thanks for the reply,my setup is :

Hks 2835 pro s

some huge bosch pump,tuner says its flows more than an 044 sorry dont have more info on on it..but he regularly uses this pump..

z32 ecu with type 2 nistune,

ebay spec fmic,

but i`m quite relieved that they are the 740 `s..

ok i removed the fuel rail and found that the new o rings (small ones) are squashed and in some cases split,

also the lil green spacer thing after the oring is squashed,the guy i had flow test them supplied new orings and pintle caps,

the caps were not the 4 pronged ones normally on these and told me i had to trim them flush with the end of the injectors,

when fitting them we they were hard to push in and didnt feel "right" to me,cap looked like then ends had been chewed off!

was told to just use the metal covers and pull them down buy doing them up this way.slowly and evenly..

there was no signs of leaking (we did check for them more than once)but surely this couldnt have been helping matters ?

You had them flow tested? What were the results?

yeah took them to a local repco workshop and they only tested for spray pattern..

they said they couldnt give me a cc report with the bench they had.

so my next step will be to send one off to someone that can test them properly.

After informing this fellow of the results he was adamant that they are 740cc,no surprise there i guess,

so wanting to give him the benefit of the very small virtually non existant doubt, i went back to the efi place and got them to do a side by side comparison,

to my disappointment it only backed everything we already have done to verify that they are in fact around 270cc,

the result was the factory 370cc injector flowed more than the red tops in question,

calculation from this result showed that the red top inj only flowed 260cc,which is spot on for a sr20de injector,

http://nissans15.com/spec.htm

there is also a video of todays comparison test and full details of the process from tuning to the test today posted by my tuner:

i am reluctant to post the link publicly on here atm as it names the person in question,he has fallen silent since i informed him of the second test today,

but I still want to give him a chance to rectify the situation first.

prior to falling silent he was saying he purchased these new and could not have sent me the wrong ones,as these were the only side feed inj he had,

so its tough and i dont like haveing to do this.what choice do i have,

I believe the evidence is clear that i have been ripped off either intentionally or by mistake,

either way I should be refunded my money on the price of the original purchase at the very least.

the video will be removed if he decides to do the right thing by me here.

if by chance anyone would like to see my tuners post on this matter pm me and i will provide the link,

i would appreciate any informed opinion on this matter.

end rant.

yeah it certainly seems that way,the funny thing is though he always peddals stuff on here,

and lots of it,so its really caught me by surprise.

and yes the duty cycle is off the charts,100% +,

we knew something was up at first start up with these inj as the the injector scaler had to be upped instead of lowered,

just to get the car to idle without being very lean.

like 18:1 lean,crazy.even with the std ecu instead of flooding the engine with fuel it was really lean.

  • 2 weeks later...

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