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thanx guys I appreciate all the input, it has been very interesting looking at it form the big picture i think i might go to a single z32, and just use 2 x 1K Ohm resistors and make a voltage divider to feed both voltage inputs of the pfc, but in saying that i dont know if there will be any problem with joining the two pfc inputs?

the powerfc takes an average of both AFM signals to work out load axis calc

you should really use two airflow meters

agreed. at $350 for a new Z32 afm it's about the cheapest thing you can buy for a GTR... hell my oil change costs nearly that much by the time I fill it with nearly 8 litres of chrono 300V (extended sump). and oil's a consumable. you only have to buy the afm once.....

the powerfc takes an average of both AFM signals to work out load axis calc

you should really use two airflow meters

sorry paul can you please elaborate on that, i understand that it needs two inputs, for arguments sake lets say the z32 is reading 2v get this voltage and divide it into two with the voltage divider, and then feed it into each input to the ecu as if it was two airflow meteres? wouldnt this work? i was thinking of also puting two diodes just so there is no interferance between the two inputs but this will drop the voltage by 0.6v so i dont think il be doing the diodes in the end, but dose any one know how much current a z32 signal out draws?

please see my drawing, it was just a quick sketch but let me know what you guys think...

post-55185-0-38035700-1297831775_thumb.jpg

you can pair up the signal wire and others have done it so you have 1 afm and run the same signal wire to both inputs

i still think you will max just the same as GTR maf is 65mm x 2 whereas single Z32 is 80mm

yes, that's my point. a single VG30 afm is not going to get you much (if any) gain over the stock TWIN Rb26 afms. sure twin VG30 meters will be able to measure heaps more air, but if you're going to do single VG30 may as well just keep twin RB26.

yes, that's my point. a single VG30 afm is not going to get you much (if any) gain over the stock TWIN Rb26 afms. sure twin VG30 meters will be able to measure heaps more air, but if you're going to do single VG30 may as well just keep twin RB26.

On the previous page it was stated that Z32s can read 370kw, so;

- for less than 300kw use the standard afms

- for 300-370kw, a single Z32

- for 370+kw, use two Z32s

Of course that's if you're only considering metering capability. You then need to look at plumbing and cost to come up with an answer.

On the previous page it was stated that Z32s can read 370kw, so;

- for less than 300kw use the standard afms

- for 300-370kw, a single Z32

- for 370+kw, use two Z32s

Of course that's if you're only considering metering capability. You then need to look at plumbing and cost to come up with an answer.

Thank you, hence the reason wanting to use the single VG30, i am running out of room in my engine bay, dose anyone know how much current draw is on the signal + wire of the afm? and i am unsure of the power expectation as i bought my turbo second hand it is a K28 Blitz turbo and i could not find much info on it... also with standar internals and only stage one cams what is the max boost that a rb 26 can handle with lets say a t76 or t88 and also how much power? running premium fuel, i know that the e85 will have bueeter fuigures but i cant be bothered mucking about.

Edited by ff_driftz

hey guys here are the pics as promised..!! notice the home made splitter afm intake pipe, way cheaper than the off the shelve item...

again if anyone knows the current draw on the afm sig +ve please let me know i know its small but i need to know for the voltage divider..

post-55185-0-64944300-1297941051_thumb.jpg

post-55185-0-30430300-1297941086_thumb.jpg

post-55185-0-11528500-1297941172_thumb.jpg

Edited by ff_driftz

It'll be interesting to see if do/don't have issues with the 90 degree and merge that close.

You tend to wanna push push them closer to behind the headlight where you've put the P/S res.

But wait and see i guess.

i am unsure of the power expectation as i bought my turbo second hand it is a K28 Blitz turbo and i could not find much info on it...

Turbo is make or break for the application. Typically people first get an idea of what sort of power they want to make, choose the smallest turbo that comfortably meets that power goal, then build whatever else is required around that. You're doing it wrong :nyaanyaa:

also with standar internals and only stage one cams what is the max boost that a rb 26 can handle with lets say a t76 or t88 and also how much power? running premium fuel, i know that the e85 will have bueeter fuigures but i cant be bothered mucking about.

Its a grey area but my guess is that you'll want to keep power below 350rwkw with a stock bottom end. Doesnt really matter what turbo or what psi, although the lower the revs the better.

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