induction kit 4 325i

[parms]

which one to go for

[reaz12345]

i put A K & N CONE FILTER ALL I GOT WAS A GOOD ENGINE SOUND BUT LOST BHP SO I PUT ORIGINAL 1 BACK ON

[darkchild]

I wouldn't bother. BMW spent money ensuring the original does the job well enough.

[snoops]

do a search this topic has been covered about 1nce each week, for performance standard is best,if youput an induction kit you will get a nice noise but probably loose a couple of hp but the noise is nice! get a heatshield or make your own and it should be fine as the hot air from the engine ends up getting suckedin.

[Simon]

If you are after noise, then foam ones tend to make the most induction noise on the M20, the paper ones seem to be quieter.

If your after performance though, save your money for a chip or BBTB.

[M5pilot]

I did some testing yesterday while mapping the Alpina.

Car is fitted with an ITG foam cone type filter with no heat sheild.

This test has been done before but no one remembers the outcome.

The air intake temps in our unit were around 25-30 degress yesterday. With the car left to idle the maximum air intake temps rose to 50 degrees. You get close to this even with a factory airbox or any competely sealed system. The reason to me is not 100% clear but my understanding is that you get heat radiation from the combustion chamber back towards the air intake.

Once we turned on our fan the air intake temps very quickly came down to 35 degrees, this is within 30 seconds. After this it comes down to atmospheric temperature a little slowly but still within 1 min.

On the dyno with the fan on air intake temps = outside air temps.

The E30 being quite flat at the front allows alot of air directly into the air intake side of things once some air pressure builds up. Air intake temps therefore drop extremely quickly.

As to whether the induction kits add any power over stock - that's the next test.

If BMW did such a great job then why is it that E36 m3's and ZM's gain 7-13 bhp with some induction kits? The reason - BMW do not design the airboxes just for outright performance, they have to take into consideration noise under load and at different points in the RPM range. The system is compromised such that the car is acceptable to a wider audience. Not everyone wants a loud induction noise and manufacturers understand this.

Thanks
Evo-S

[chinchilla]

BMC Carbon firbre induction kits make the best sound well worth it even if means loosing a few hp.

[ed325i]

ITG induction kit ?

[reggid]

As to whether the induction kits add any power over stock - that's the next test.

when will that test be?

cheers