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RB20/RB25 AFM max power?

Remix-

By Remix-,
in Engines & Forced Induction

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  • 7 months later...
bumble_bee Rising Star

bumble_bee

Posted
Posted
Your Engine warning light will also flash in a particular sequence when your AFM maxes out. This is often mistaken for knock... I am not sure what the 2 different sequences for knock and AFM Max out are though...

are u sure about this??

coz ive neva seen this, but im still runnin a stock comp.

i believe pfc can b setup to do this..but i think it does it for knock as standard..

other than that..

yeah, it feels like ur car can go alot harder..but it cant.

feels like u've hit a wall..

also, ive been told by tuners that the ecu has stock maps that maxs out evan before the afm reaches max...but im unsure about this..

and u cant run a z32 afm on a stock ecu anyways..

ive got an apexi neo and it displays my afm %, thats another way u can see ur afm %.

bring on a map sensor :pirate:

Benzino33 Experienced

Benzino33

Posted
Posted

Hey guys interesting thread. Just wanna ask, is it time for a new afm?

I have a standard rb25 afm (pink label) and got a hi flowed turbo.

I made 215kw on 10.5 psi on a stock ecu. Dont really wanna go much further but would like to do a run at higher boost before putting it back to 12psi.

Will my afm crap itself soon? Should i go with a z32 just in case?..

cheers guys

Benzino33 Experienced

Benzino33

Posted
Posted
Yes, it is true, you need a remap

Oh really?, i just thought i could just put one on.

cheers for that tho,, but do you think at the power level i'm making now, I would need to upgrade?

I am happy to keep it where it is

mad082 Grand Master

mad082

Posted
Posted
Oh really?, i just thought i could just put one on.

cheers for that tho,, but do you think at the power level i'm making now, I would need to upgrade?

I am happy to keep it where it is

no, basically it is like measuring up a hole in the wall to have a window made and having someone call out measurement in cm, and then changing the person giving the measurements and having them measuring in inches but not telling you, so you think when he says 5 he means 5cm, not 5 inches which is 12.7cm. you are going to end up with the wrong thing.

as for how much power, you can generally get to about 250kw when they are getting close to maxing out. the people who said they were having it max out at under 200kw are incorrect. that would be the ecu packing up it's bat and ball and going home. it is called rich and retard and it is a safeguard in the ecu. it doesn't mean the afm is maxing out, just means the ecu doesn't like the amount of air going in at that load point in the map so it cuts out. i had this happen in my 33 when i wound the boost up.

You can tune past the AFM - its just not recommended for joe-average type people who don't check things regularly, sensors, warnings and so on.

Better to have the AFM to suit your application.

exactly. it is a little bit of a "hope for the best" type of situation as you are putting in the amount of fuel that it needs at the time of the tune, but if conditions alter a bit it can end up being not enough fuel (or too much)

Pal Veteran

Pal

Posted
Posted (edited)

was done by a very good tuner over here. i have had my car on this dyno over 30 times now and matches very well to other dynos around perth (dyno comps). my guess would be that it it is at the limit now, i asked him if i needed a Z32 but he said no, he can tune it with the stock one. the engine happy revs, minimal knock (everytime i look it about 10 to 20 peak) and no warning lights

Edited by Pal
ARETHT3 Enthusiast

ARETHT3

Posted
Posted

i just wanna clear things up for myself...

PPl keep putting RWKW as a guide to when the AFM is maxing out... would this really have anything to do with it... what happens if you have made good power from mods such as cams exhaust FMIC etcc..this dosnt effect the AMF does it... so is it raelly only the psi your running a better guide to testing when it will ma

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

No - You need a certain amount of air to make "X" power... its not boost related. The AFM does not care if your running 10psi or 100psi.

What it cares about as follows - Max of the AFM is say, 200rwkw and you need 100CFM to make that power.

Large turbo 10psi = 100CFM

Tiny turbo 100psi = 100CFM

So its predominately rwkw driven based upon this.

Yes i realise the above example is rather ridiculous and ive probably got it slightly wrong - but it's all i can think of atm.

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