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Judd, I know of the restriction that is maf,

The link is not going to stay, as such I may need to quickly remove it and go back to factory. I still want to get either a wolf 3D or a LTX 12 Microtech. Im in the process of making up an adapter to replace the Maf to bolt to the air box. Also thinking of making the piping bigger from the air box to the Turbo inlet.

Regards Damqik

How is a maf restrictive? An 80mm hole will flow a lot of air, or if you need 90mm - you could use an infinity AFM with a power fc.

Only good for idle, what about af metering on cruise? Doesnt MAF use closed loop = better for part throttle and cruising? Also, if you upgrade a turbo, MAF would be better, ie you dont need to immediately retune before you drive as MAP measures only pressure not volume of air flow (different turbos flow diffent volumes at the same pressure).

I am not saying MAP is bad, just pros and cons for both. I believe I have seen some pretty huge hp cars out of Japan running power fc.

From what people have been saying, the new wolf 3d v4 sounds pretty tasty - in the past they have been an entry type ecu, but the new one sounds sweet.

Autronic is made by one of the developers for Motec (he split from the company), it is a bit dearer than a wolf - but would be very hard to fault as an ecu

The power fc provides full stock ecu functionality, very easy to tune and are also a tried and tested (and very effective) ecu.

At the end of the day - if you are not intending to tune the car yourself, speak to your workshop and ask what they recommend, and what they can deliver with that ecu.

another 2cents worth.

Im with Steve, AFMs on CA18/SR20 etc are very restrictive as they have a small bore, i think approx 48mm. Crappy and should be thrown inthe bin!!!

RB AFMs are 80mm in diam, thats over 3", and who here is running 3" pipe to their turbo??? You need to be trying pretty hard to get choked flow thru an 80mm opening.

Choked flow is when no more air can physically pass thru an opening/orifice, ie thats why restrictors are used in some categories of motorsport, to limit airflow and hp. I think rally cars run thru 32mm restrictors and they still make good power, though their is an increased expense in engineering diffusers before the restrictors.

AFM cars are more flexible when bumping up boost etc, when MAP sensed cars can need re-tuning to suit. Also cams can sometimes upset MAP sensed cars due to unstable inlet pressures resulting from lift and duration of cams... read 1000-1200rpm idle.

Economy/emmisions is increased with AFM, thats why manufacturers use it in order to comply with ever tighter legislation.

But please stop saying that RB AFMs are restricitve and should be resigned to being pencil holders, they are an example of how AFM should be made.

Remember not all AFM are created equal.The Nissan RB unit is a Hot Wire Airflow Meter (Nissan RB) that is far superior to crappy Vane Airflow Meters , or troublesome Ultrasonic types.

Whichever way you go OE AFM or MAP, set up and tuned correctly you will reap the rewards.

I hear what youu guy's are saying about maf and I think Nissan Japan got things right first time for a street car, but I disagree about the 80mm opening as the hot wire probe would reduce the amount of air that could travel past, and then theres the screens (which I lost the week after buying my car 2 1/2 years ago) it would be more like 60mm opening at the end of the day. I'm currently running map, I can run in closed loop (link ecu) so no issue there with regards to the cam issue I can run mixed mode TPS/Map so also no prob's

I guess its different strokes for different foke's like rb20, rb25, rb26 & rb30 and all the others mixed between. so it is with MAP & MAF one guy will say one thing another will say another thing.

We all like 9 sec skylines dose it matter how they do it?

Motec are an Aussie ECU, and are used internationally in many forms of motorsport. 2nd hand they still go for upwards of 3k with all the bits, they are a well engineered ECU.

The hot wire probe is what about 4mm in diam max?? That does reduce surface area, but as a percentage????

As i understand it the reason big HP cars run MAP sensors is beacuse a MAP sensor will run anything from a Charade to 1000hp drag car, as long as its not running more boost then the sensor can withstand.

Now problem with AFM is that they need to be sized for application, i think only the yanks make aftermarket AFMs for their chevs etc. An MX-5 Vane AFM isnt going to run your T88 RB26.

Not too many factory cars making 600hp for us to go and steal the AFM off. Then theres the prob with ECUs recognising the voltage signals, ok almost universaly 0-5V but what voltage equates to what airflow.

So what happens, aftermarket ECUs recognising that AFM are application dependent (ie not universal), base their computers on running MAP sensors, meaning they can be used for any hp application.

You and I see aftermarket performance ECUs using Map sensors and think they are the duck guts Max.

Not knee capping MAP sensed cars or their owners, im standing up for the poor old AFM that is forever being bashed. So yes MAP are used on big hp cars but not for the reason many think.

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