mr_vaughn

iTrader: (1)

I was looking inot upgrades to my s5 AFM along with getting a Greddy E-manage.

I saw in the manual that the 20B is the type of AFM.
1. Is it bigger than a S5 AFM?
2. Anybody got some pics of either of NA/turbo AFM?

RETed

Again, why would a bigger AFM offer you in performance?


-Ted

jacobcartmill

iTrader: (6)

maybe he can pull enough air to make the s5 AFM a restriction?

ddub

Why wouldn't it? bigger passage through the AFM = more flow, right? This is the concept in a lot of aftermarket MAFs for other cars, like the one I have for my Ford Escape.

pip

As ted mentioned before in a similar thread, the stock afm and the stock ecu max out at approximatley the same time. Meaning if you have a bigger afm youre still left with an inadequete ecu, so you might as well go stand alone w/ a map sensor and ditch the afm all together.

jacobcartmill

iTrader: (6)

or it all really doesnt matter because very few NA's will ever even get close to that point.

thanks.

RETed

The stock boost sensor maxes out at 15psi.
The stock boost sensor retards ignition timing.

The stock 4x550 fuel injectors can only support about 250bhp at the flywheel.

The stock fuel pump, with full voltage, can only support about 300bhp at the flywheel.

Moderate increases in power is fine with the stock ECU.

If you looking to make over 300hp, the stock ECU is not efficient at controling fuel and ignition for power levels that high.
This is where an aftermarket stand-alone EMS is highly recommended.

The stock 20B Cosmo AFM is rare enough to find.
You're going through all that trouble to increase airflow capacity, but the stock ECU and fuel system still need to be addressed.
You're better off spending that money taking care of other things like the exhaust, intake, CDI box, boost control, etc.


-Ted

ddub

Are we talking about n/a's??? The thread starter has a turbo

ddub

That's true, makes sense. My first thought was just how lots of new cars and their MAF systems can be upgraded with a high flow one for good gains. But what you say all is very true.

mr_vaughn

iTrader: (1)

i know Haltek or Wolf or Microtec would be better....but
it is all about the challage and it is MY CAR......

Ted is consistantly preaching stand alones....
I know the benifits....

The reason for posting is to get my questions answered not to find a toatl solution....

gsracer

Piggy back systems can retard timing with external pressure sensors.

Isn't that backwards? I wouldn't trust the stock fuel pump to even 250bhp. I made 232 rwhp with the stock injectors and the walbro. Yes, I'm sure the fuel pressure was probably 7-10 pounds higher with the addition of the pump. However the fuel pump is the first weak link, not the injectors.

The stock ECU compared to todays technology is both slow and outdated, I agree. However, I think you're being rather conservative wit h the 300hp number. Why do you list a stand alone EMS as one of the last modifications on FC3S Pro however?

If the 20B wasn't such a rarity, I think the afm swap might actually be worthwhile. A common swap for turbo MKIII Supra owners involves the AFM from a Lexus and 550cc injectors to match the new AFM. The bigger AFM compensates for the larger injectors and is able to run near stock mixtures. An obvious advantage to this would be the larger injectors that are now run like stock. However, I think FC owners will simply have to deal with the stock AFM since obtaining the 20B AFM would be very difficult outside of Japan IMO.

I think a middle ground between a SAFC and a stand alone has been needed for many years to be used by fc owners. Henrik is making great progress with the rtek ecu chips, and the e-manage looks to be very promising as well.


For the most part Ted doesn't push stand alones (haltechs) to the same degree as many other members. If I had the finances and time to be running an e6k right now I would.