Air Filter

[azruss]

If you look at the air input snout on the stock FI air filter box, you can get an idea of how much air is really required for these motors. The size of the snout is puny compared to the surface area of any flat or cone filter. The only time you will get any vaccuum on the filter side big enough to slow the AFM door from opening is if you have a terribly dirty filter and I doubt that even that would have any effect. The amount of air that passes by the AFM door when it goes from closed to fully opened can't be any more than a few cubic inches of air. If you do have an air input restriction you will notice it more at full throttle speed with the motor at high RPM. This is where you air demand is the highest.

[kacperix]

ok, understood,
i misunderstand a mix some facts, because i read/think also about changing not only filters but whole size and lenght of the system intake. And than You have to calculate and count everythink...
than i thought if i will make bigger whole system i can have problem with the idle speed...

Check and adjust the parameters idle Connect tachometer. Start the engine warmed up to normal operating temperature and read the idle speed. The actual value of 950 + -50 rpm / min. If necessary, adjust the idle speed screw by setting the throttle bypass channel. Screwing screw reduces the idling speed, and its twisting - to increase the idle speed.

this is adjustment which i have on my mind...

i have some problems on the cold system, after i start idle speed are ok, but if i push the trottle engine chokes and can switch off, when i make it gently rpm go up but dooesn't want to go over 4rpm. When i ride on the cold engine i can't make a full trottle (engine choks) also when i put on the neutral gear durig the ride from 5k rpm they will drop to 500rpm or even engine can switch off.

On the hot engine everything is ok. only on the cold system.

I think i can have some problems with the air system cause i have some leak of air after afm.

ps. sorry for my english

[Odoyle]

I found this performance air kit for sale at international-auto parts any it got me thinking...http://www.international-auto.com/power ... r-kits.cfm

My only concern is that it says its not legal on US cars... if I was to purchase it and install it regardless what's the worst that could happen?

[Kevin1]

I think i can have some problems with the air system cause i have some leak of air after afm.

Before doing anything else, fix any air leaks in the intake tract. Any air leaking after the AFM is unmetered air entering the engine. And since it is unmetered, there is no way the ECU can add the correct amount of fuel for the total amount of air inducted. There is no mechanism in the L-jet system to compensate for intake leaks.

Fix the leaks before trying to diagnose any running problems. That alone will yield a better running engine.

[4uall]

follow up to Kevin

http://www.fiatspider.com/f08/viewtopic ... &sk=t&sd=a