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Q45 AFM & Powerfc chasing 260rwkw - Overkill?

The Mafia

By The Mafia,
in Engines & Forced Induction

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The Mafia Grand Master

The Mafia

Posted
Posted

Hi Guys,

I'm looking at getting a q45afm, and were wondering if it would be too big.

I have a fmic, pfc, full exhaust, GT30 (.7ar) turbo and other systems to support.

Is there such thing as getting an AFM thats too big? I know this one is a size up from the z32, but will it work just as good? The reason I am opting for this one is its one of the only ones I can find for a good price.

Let me know what you think.

I'm only chasing 260rwkw.

rob82 Mentor

rob82

Posted
Posted

Generally the best way of deciding what fueling components to use is to choose the injector/AFM that will just get you to the desired power you are after. This way you maximise the resolution in your operating range.

That said if a Q45 is the only AFM you can find at a decent price then I would just get that. I think you can change the resolution of the specified AFM within the PFC based on a percentage amount also.

paulr33 Grand Master

paulr33

Posted
Posted
do you think I'll just be able to plug and play?

My mate is a boiler maker, and he can do anything for me to make it fit.

<img src='http://members.iinet.net.au/~sennan/pod bracket.jpg' border='0' alt='user posted image'>

were you asking me or asking in general?

youll need to adapt wiring, adjust all your pluming to suit the 90mm instead of 80mm and also choose the vh41 afm in the powerfc menu. i would have your tuner check and do it to make sure it doesnt give wacko results. the power limit of the q45 has been questioned a few times, with no real proof or evidence. would be great if someone could say i have this much, here is the graph or what not. the wiring is on my site

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

yeah I was asking you.

Just curious if I just plug the AFM in, will I just select it in the AFM menu, and thats it, no further tuning required?

Or does the PFC need to be retuned due to the different readings from the AFM?

a little confusing...my apologies

paulr33 Grand Master

paulr33

Posted
Posted
yeah I was asking you.

Just curious if I just plug the AFM in, will I just select it in the AFM menu, and thats it, no further tuning required?

Or does the PFC need to be retuned due to the different readings from the AFM?

a little confusing...my apologies

well im not entirely sure having never done it. that being said when you choose the afm in the powerfc menu that would be the all the adjustment that would be required in theory? now that wont work in practice so im not sure, i would say get your tuner to select and then do a dyno run checking the a/fs cos it might go mega rich or lean. a guy in melb fitted one and then it was running mega rich but im not sure on the reason so its hard to say. i guess if it pops n farts a lot when you choose the afm then its mega rich

rob82 Mentor

rob82

Posted
Posted

The mixtures will most probably change I'm sorry to tell you. In theory as long as the MAF calibration within the PFC is correct it should be close but it is never really the case in practise.

A little off the subject but - I had to retune a twin screw supercharged VY crewman the other day with a new VZ 90mm MAF. The car was running the standard delphi ECU. What i did was copy the MAF calibration table from a VZ into the ECU. Now you would think with all the corrections available to the ECU that this should be enough but unfortunately it still needed some tweaking. Just goes to show that theory is still a fair way off compared to practise.

BBQ Community Regular

BBQ

Posted
Posted
Hi Guys,

              I'm looking at getting a q45afm, and were wondering if it would be too big.

I have a fmic, pfc, full exhaust, GT30 (.7ar) turbo and other systems to support.

Is there such thing as getting an AFM thats too big? I know this one is a size up from the z32, but will it work just as good? The reason I am opting for this one is its one of the only ones I can find for a good price.

Let me know what you think.

I'm only chasing 260rwkw.

A z32 will be enough to get you to the 300kw mark.

A q45 will give up 350+ but it won't be street drivable as it will have problems idling.

Cubes Grand Master

Cubes

Posted
Posted

Just to note.

For some wierd reason the RB20 PowerFC has a different AFM calibration airflow curve to that of the RB25 PowerFC.

Looking through a few others i.e S13,S14,S15 etc they all have a different airflow curve calibration for the same AFM?!?

I don't understand why they would do such a thing. :(

Jim Rising Star

Jim

Posted
Posted
Around about the 200rwkw mark you want to look at upgrading to a z32.

ive seen this on the forums heaps but i have seen 2 cars (both friends) that made 250+ rwkw with the standard afm's .

both these cars made that power safe and comfortable with no issues.

Any one else tried pushing a standard afm until they ran into trouble?

SK???

cheers ..Jim

paulr33 Grand Master

paulr33

Posted
Posted
A z32 will be enough to get you to the 300kw mark.

A q45 will give up 350+ but it won't be street drivable as it will have problems idling.

hi bbq

can you go into more details on the idling problems? do you know any specifics about it??

cheers

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