In another thread:

https://www.evolutionm.net/forums/sh...threadid=28852

We got on the topic of drop in filters, specifically K&N or Ralliart. Since I'm very interested in an accurate answer and that thread was a little off topic for this discussion I wanted to start a new thread. One member said that:

"Originally posted by boostedwrx
dont get a K&N or Ralliart drop in. Shiv verified that these filters change you MAS readings substantially. With JUST the Ralliart drop in, I was running 2 whole points lean on the Wideband o2 meter. Like 13.0 or something....

Dont get an air filter unless you have access to a dyno session.

The stock air filter is by far the best. "



Does a K&N drop in cause a the car to run rich?? Can anyone really tell without a dyno? Has anyone dyno'd this to see for sure if the K&N helps OR hurts the performance??

 

Maybe that is the secret to the "Ringer car" Running that lean could justify 20+ horsepower. I am awaiting reponses on this question also. Why would Ralliart sell it, if its not safe?

 

to make money, like everyone else.

 

On my previous Mitsu turbo car I ran a K&N drop in. It was certainly the seat-of-the-pants dyno but it "felt" faster. I'd rather know for sure before I get a K&N fo rthe EVO.

 

We've tested a K&N drop in filter on our shop car and didn't see any significant MAF misreadings. At least not as significant as we've seen with some foam panel filters which were downright scarey. However, we didn't see any gains either so I'm not so sure it's a worthwhile upgrade unless you have to spend $70 or so. Especially considering the cumulative surface area of the stock filter. We'll test the K&N again now that the test car is running substantially more airflow than it was back when we did the first test. But I don't expect it to be worth any real gains based upon what I've seen so far.

Cheers,
shiv

 

shiv,
Have you tested the cone filters? You would think the air flow would be straight since it is pretty open to pull in the air without the different pressure zones like in the air box.

 

Thanks Shiv...very helpful.

I guess for a stock EVO the stock air filter is as good or better than a K&N?

 

bump

 

I recently purchased a K&N filter and have seen virtually no difference. Grant it there are no 4 wheel dyno's around here to back this up but by seat of the pants it doesn't feel any quicker. It is not any louder and still fills the tailpipe with black soot a definate sign of running rich.

 

I think that's a safe thing to say for most applications. The K&N *may* be of benefit in a higher flower 400+hp application. But since we're not quite there yet, I can't be certain.

Cheers,
shiv

 

Shiv! You have time to post and no time to send me my map! lol

 

Yea I had the Ralliart foam panel filter, shiv verified that my mas readings were all over the place. He tried tuning around it, but it was very difficult and I think it actually hindered my total power output.

 

Just emailed it to ya... I had to dig through my map collection to find the right one.

Shiv

 

Xtcnt and I are going to compare the Ralliart Panel Filter before and after on his road dyno tommorrow. The road dyno gives us actual airflow dynamics and hopefully the HP gain/loss if any is within the resolution of the dyno. We'll report back here. Without a wideband, we can't comment on the A/F ratios.

Speedlimit..

 

We made a baseline run with Xtcnt's EVO, then installed my Ralliart Filter. We made two runs stock, then two runs with the Ralliart. The Ralliart added 5 HP on both runs as compared to the stock filter. Also, we both noticed that the car pulled stronger at higher RPM and the turbo spooled a little quicker. I was very pleased. We'll try a K&N filter next.

Speedlimit...