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Hi,

I'm almost finished my forged rb25 (stagea motor) in gts4 r32. Expecting 350awkw and am wondering about my afm options.

*please don't tell me maf sensor etc - that's not the topic here.

1) I've always wondered how do you know when your std (in this case s1 stag) afm is running out of chop?

2) z32 = 80mm q45 = 90mm so why don't I see more high powered nissans with q45's?

3) how much can I expect out of my std afm with all the supporting mods? (3076, e85, cams etc)

Many thanks

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Because Z32 is same physical size as standard AFM, therefore bolts to airbox and connects to turbo intake with no stress. Plus, is good for 500HP. Seems like a good enough reason to use it.

Oh, and where you said "*please don't tell me maf sensor etc" you really meant MAP sensor.

I've seen genuine Nissan q45 afms on eBay for $120, genuine z32's are $280. 90% of high hp nissans will be running pods, so for the sake of another silicone adaptor would the q45 be a better idea if I was potentially expecting 550-600hp?

M A F means Mass Air Flow, means the same as A F M means Air Flow Meter.

MAP not same. Therefore you say potato, I said carrot.

Haha ok, now that I've learnt about the difference between MAP & MAF, has anyone chosen a q45 over a z32 & if so why?

Thanks

Yes, people have. If you have a genuine >3" turbo inlet then a 3" AFM can cause a restriction, so it makes some sense to put a bigger diameter AFM in.

I am of the opinion however, that if you have a compressor that big, you probably shouldn't be using an ECU that requires an AFM anyway.

I am genuinely amazed that you are building an engine planning on decent power, and don't know much about what afm to use at this stage.....

How is that amazing?

I'm merely asking about the differences between the z32 and q45. I knew the std afm won't cut it was just curious if anyone knew at what point it would give up.

Sorry if I don't know as much as you mate

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