Hey yall. i have installed 370 injectors but i seem to be having a/f problems. its reading too rich and it seems as the ecu is not making adjustments. i lowerd the fuel pressure to bout 30psi and the a/f got around 14.7 which is fine. but occationally drops down to 11's sometimes, its just too uncontrolled. my o2's should be good as i changed them and also dont get any codes for them. Is it possible that I may need a z32 MAF so that the ecu can better adjust the a/f of them injectors?

 

You need the z32 maf to run it normally

 

Are u sure. any reason why though or a lil short explanation.

 

it will work without it but ull run way rich and may not be able to get it lean enough with tuning....the Z32 maf will allow u to get the proper usage out of teh Z32 injectors...but for an NA application thats too much fuel really not needed...if ur boosted...i recommend both highly....u really need boost to take full advanatage of thre z32 equipment...ur real problem is 370cc injectors on an NA motor....used DE-K or 3.5s if u feel stock ones are not up to par

 

ok cool then. looks like i might have to boost then


Edit: I just thought about this, shouldnt the o2's help the ecu make correction anyway, regardless of how much fuel is being put out? i had my fuel pressure at 45psi with my other stock injectors(at idle) and the a/f would still read 14.7 after a few minutes of the ecu adjusting, why wouldnt it do the same with these injectors?

 

lol...thats awesome that u just decide to boost....the 02s will make the correction to a point...but the ECU thinks it using much smaller injectors...the ECU adjusts fuel by injector pulse.... for example no real numbers.....1 pulse of a stock 4th gen injector 5cc of fuel...the same pulse of Z32 injectors 10cc.....teh ECU will only lean it out soo much because it things its using injector that are puttiing out more than 100cc less per minute of fuel.....the ECU can correct fuel with stock injectors with raised Fuel pressure cause the ECU has that internal adjustability...that same range with the larger injectors the higher you go will limit the adjustability the ECU can do

 

that is the explanation i have been looking for.thanx alot. im calling junkyards today for a maf

 

Z32 maf is bigger so it sucks in more air, less air is read so less fuel is sent by the ecu thus no longer being rich.

 

I just contacted junk yard in virginia, $95 shipped. I will be sending them an order form with payment. thats a good price right? 30day warranty and they are goign to include the plug.

 

Sounds decent, about what I would pay

 

Wont he still be rich...not not nearly as much...but still a little more than stock or does it fully correct.

 

The ECU corrects it enough to run like stock. WOT might be different but under closed loop it will run like stock.

 

thats what I figured...Someone needs a Vafc/Safc

 

right now i care about closed loop. i calibrated my wideband this morning, and reads more consistant, at cruising its in the 11.4's, at idle low 14's high 13's, under acceleration it goes in the 10's. I wanna fix the closed loop, then ill re-tune once i get the z32 maf. (I already have vafc2).

Sometimes occationally at idle the car starts shaking a bit and a/f leans out to bout 16's. then after a while it goes back to smooth idle and a/f goes back down to 14's. i cant freaking understand why thats happening!.

 

A33B injectors = A32 injectors


It's O2's not 02's

 

VQ30DE: 259cc
VQ30DE-K: 290cc @ 3.0 BAR (FBJC100)
VQ35DE: 315cc @ 3.5 BAR (FBJC101, FWD versions)

VQ35DE: 335cc @ 3.5 BAR (FBJC100, 350z etc.)

 

Getting the z32 may help BUT youll still need something to tune with, you may as well save your money. Unless youre maxxing out the a32 MAF there is no point.

Negative, the dimentions of the A32 MAF and Z32 MAF are basically the same thing. The difference is in the electronics inside. A Z32 is calibrated compleatly different so the voltage will be lower for the same airflow. Thus it can handle more hp output.

 

but for reals...if not boost.. no need for 390cc injectors in the first place

 

Well too late now lol. I already ordered it. also I already have something to tune with VAFC2+wideband.

I have a question: right now if I tune to about 13.5 or lil less, ofcourse my timing will advance the same way it did for SR20 long ago and same way it did when i had my stock injectors few weeks ago (advanced 9 degrees). the question is, when i get the Z32 maf, and tune to 13.5. will there be less timing advance since i wont have to take out so much fuel?

 

hmmmmm..... I do not know....hopefully someone else can answer that

 

The VQ30DE runs @ 3.0 bar. A little elementary math and you could see how they are the same (A33B = A32)

Not the same part #, but as far as flow characteristics are concerened, they're very similar if not the same.



Depends on how much voltage you take out. In theory, yes, timing advance will be lower.

 

yes i know Vq30de is at 3.0 bar so I assume its 259cc at 3.0bar so how can 259cc at 3.0 bar be the same as 290cc at 3.0bar

 

Different injectors.

 

thats what i am trying to say cause i suggested using de-ks since they flow a little more...i know not a ton more.... if the original poster wants to run larger injectors on an all motor car.........question to Streetz....y are u using Z32s in the first place.....where u planning on boosting soon or some other reason

 

The DE injectors were tested to be ~ 270cc (tested by members on here).

With that said, 315 @ 3.5 Bar = 270 @ 3.0bar

DEK = Z33 inejctors, same principle as above.

Anyone want to buy some FBJC101's?

 

270 still is not 290 thats still 20cc difference now seeing as DE injectors flow 11cc greater than advertised according to Jime's post which is where i got those numbers from one is too assume the De-Ks will flow a bit more than advertised as well UNLESS there isactual flow data to show that they are 290cc...either way still negating ur statement A32 injectors = A33b......cause equal mean the exact same...hence the differernt connectors alone making them not equal to each other...hence U know we are arguing about this purely for fun a NOOB seeing that would interpret A32=A33b injector statement meaning they are interchangable with no modification once so ever...but we go back aways and know this is argument is purely for fun

 

Seems like you're confused. I stated A33B injectors = A32. Too vague and not true, but my discalimer is this FYI, A33B = FWD VQ35, 315cc @ 3.5

 

.........ahhhh....se eu got me confused by throwing in the A33 BBBBBB part...i has DE-Ks in my head cause thats what i had originally posted......

 

VQ30DE side feed injectors flow closer to 290cc @3bar

The VQ30DE uses a side feed injector. VQ30dek and VQ35 uses top feed injectors. Can't just use The FBJ series in a VQ30 unless you want to change fuel rails.

To the original person who started this thread....why are you using z32 injectors in the first place?

 

Well my car was undrivable because of the failure of the stock injectors, a buddy of mine already had z32 injectors that was not going to use (since he did 3.5swap) and i needed the car asap. so i just put them in.

 

there are a set of stock 4th gen injectors for sale in the classifieds if u want stockers

 

mehh, ill stick to these. They go good with my next power adder