Z32 MAF with AFC in R33 RB25DET

[250sxGTST]

I have an 89 240 mostly stock RB25 with Z32 MAF AFC FMIC 3" exhxhaust. I made 272whp @ 9psi. I want to run 480cc injectors with HKS GT2540 but i dont know if the AFC can control the injectors, right now im at -49% to idle it and -40% to -45% at wot. how can I tune the car for bigger injectors when im almost maxed out with the stock injectors. Thanx for any help. By the way the car ran 12.55 et in the 1/4 in street trim with full interior at 10psi on pump gas and drag radials.

[Carl H]

answer is no.get a power fc or something else because a maf manipulator will only cause problems and potential engine damage.

[250sxGTST]

I dont exactly have the money for PFC right now, I intend on saving up for AEM EMS as Ive had alot of success tuning with it on customer cars. My nissan just has me confused because ive used the AFC many times before with good results and currently i am happy with it on my RB. Theres no way i can use it for even a conservative tune? If not does anyone have something better thats plug and play for sale?

[SleepingTalon]

I've got a rb25det w/ safc, 550's, 2540, and just bought a z32 afm. What input/output settings are you using on the SAFC? Is in-2, out-4 correct with the z32 afm? The car is making 385whp at 16psi on pump gas, and the maf is now maxxed out. At any rate, I've had no problem getting the safc to control these injectors, and have used the safc in 750whp applications, so it'll work no problem with your setup.

[Carl H]

I've got a rb25det w/ safc, 550's, 2540, and just bought a z32 afm. What input/output settings are you using on the SAFC? Is in-2, out-4 correct with the z32 afm? The car is making 385whp at 16psi on pump gas, and the maf is now maxxed out. At any rate, I've had no problem getting the safc to control these injectors, and have used the safc in 750whp applications, so it'll work no problem with your setup.

while the safc _can_ control big injectors and diffrent mafs, it seems that the general consensus is that it still is fooling the stock ecu.from what research ive done on various forums and what not it seems that (to me) the best route is either a standalone like a pfc or aem, or to use the safc in conjunction with an ecu chip.i had an emanage on my car and while it did work i didnt like how adding or subtracting 'fuel' would mess with my timing maps, yes the emanage can correct for this but it was more hassle that i didnt want to go through with.i also noticed that on my friends car (440cc injectors, z32 maf, safc) that after the dyno tune that it idled weird, presumably due to the safc correcting for maf and what not.

i suppose all in all its not that bad of a device and it really is up to personal prefrence but for all intensive purposes i dont care for them and wouldnt use one on my car.

imho if you are looking for a moderate power rb20 or rb25 then a tweaked ecu and safc is just fine, but for one thats agressively modded a safc wont cut it.just my .02c on the matter.

[Kansei240sx]

I raise this question then, If i have a Z32 MAF, with pretty much a stock RB25DET motor, ( Greddy intake manifold , FMIC, bolt ons ) and i use a z32 MAF, do you think i would run fine?

The reason i ask is... I sent my wiring harness off to the wiring specialists and they did a good job on the harness minus one thing..... The MAF plug looks like this... {ooooo} instead of (- - -) this.... I have no idea what in the fuc|< the plug is, I KNOW its the MAF becuase of the wires and sheilded twisted pair, plus the fact that its lengthened, i will put up some pics of it later, its just got me confused as hell becuase i know its not identical to either the stock maf, z32, SR20, KA, OR Q45 MAF connection....

Now the way its been wired up is 4 out of the 5 pins have been wired up something like this... {xoooo} , i am confused, can anyone help me? or should i just go to nissan and get the similar Skyline R33 looking maf connector since its just a pretty common three pin connector and re wire the MAF that came with my Motor set?

[Carl H]

I raise this question then, If i have a Z32 MAF, with pretty much a stock RB25DET motor, ( Greddy intake manifold , FMIC, bolt ons ) and i use a z32 MAF, do you think i would run fine?

The reason i ask is... I sent my wiring harness off to the wiring specialists and they did a good job on the harness minus one thing..... The MAF plug looks like this... {ooooo} instead of (- - -) this.... I have no idea what in the fuc|< the plug is, I KNOW its the MAF becuase of the wires and sheilded twisted pair, plus the fact that its lengthened, i will put up some pics of it later, its just got me confused as hell becuase i know its not identical to either the stock maf, z32, SR20, KA, OR Q45 MAF connection....

Now the way its been wired up is 4 out of the 5 pins have been wired up something like this... {xoooo} , i am confused, can anyone help me? or should i just go to nissan and get the similar Skyline R33 looking maf connector since its just a pretty common three pin connector and re wire the MAF that came with my Motor set?

personaly i would run the stock maf until you maxed it out, when you upgrade the maf you loose the finer resolution that the stock maf gives, which is why most ppl dont run the q45 maf unless the car is high hp as it makes it hard to tune at low airflow levels.

from what you have described it sounds like you have a rb20 maf plug on your harness, which is fine and all as the rb20 maf is the same as the rb25 (hardware wise atleast however plugs are diffrent iirc), so it should work, but as you said if it doesnt match the maf you have then perhaps some rewiring is needed.pics would help tho.

[Kansei240sx]

OK

Here is my RB25 maf, and pics of that MAF connector, i've narrowed it down in the RB FSM i have and the connecter looks almost if not the same as the RB20E's, im just not sure if the RB20E MAF is the same as the RB20DE/T's.



Could i just go find another connector that utilizes the same shape and plug style for my RB25 MAF? Becuase thats what i'd like to, considering i wont have to spend much money and time looking for an RB20DET maf, i dont have the time really, but it seems ill be doing nothing but taking more downtime as it seems.

[250sxGTST]

I do have my SAFC set at -2 in -4out. Thats why i cant figure out why im pulling almost 50% out to tune the car. I definitely have it tuned close. It runs perfect idles good and made reasonable power on the dyno with a wideband. What HI throttle setting are other peaple running with a Z32 MAF?

[foCk]

I chipped my ecu to compensate for my inectors and fine tune with a SAFC-2 and wideband o2. works very well for me so far.