CAI - Air filter upgrade and its effect on power output.

[Biff 0]

Hi y'all

I'm thinking of buying a new filter unit for my motor (96' 328i), one of those panel (not a pod unit) jobbies in a carbon fibre housing. The guy in the shop reckons they're good for another few bhp, while a guy in the local garage says they're crap and fitting one will have an adverse effect on performance.

I see by some of the posts here that many of you recommend this upgrade, but I'm wondering whether any of you have any hard facts to back up the claim of increased performance, such as dyno test results etc.

Many thanks.

[cainchapman 0]

As a rule of thumb:

For every 10 degrees Celcius that you reduce the air temperature to the motor, you get a 1% increase in power.

[vnz 0]

Im thinking about buy an air filter on TM, just wonder can I put it in by myself or have to the car to the workshop. some people told me that put on an air filter is pretty easy, just take the old one out then put the new one in the black box, but some other said u need to change the pipe as well, a bit confuse, can some expert in here give us some help plz, cheers

this is some I found on TM

[Biff 0]

thanks for the responses so far guys.

[Biff 0]

messing with small bits like filters will only give a kilowatt or two. If you want a significant power increase do the exhaust I got 12 kilowatts, with a few other minor mods mine is now 168 kW compared to stock 142, with more torque across the whole range.

What pipe did you fit to achieve that increase? Or can I de-cat the stock pipe and risk Greenpeace harpooning my arse?