Hey all... and Cobb guys if you are reading this. I am about to buy a TBE and have a green filter, just wondering... would I likely be ok to flash the stage 2 map with the one that uses the HKS panel filter since there isn't one for the green filter? I guess I could install it and then just log and check for knock right?

 

Yeah, you should be OK with the HKS panel filter map. A log of fuel trims and knock would be useful afterward.

 

yeah, i'll make sure that I log it and post it up for people to check it over and make sure it's cool. I figured the flow from the HKS filter to the green filter can't be that much different though.

 

I don't get it. Why do you all want to replace the stock intake or filter? Go back a while and a number of tuning shops demonstrated that when they flashed the ECU with a tuned map they pretty much negated the effect of an intake. Is the couple of peak hp digits you might gain with a filter worth the hassle?

 

The airbox is designed for the paper filter. From what I have been able to gather. Tuning negates the effects of an intake.

The popular hypothesis of why the filter makes power untuned is because it skews the MAF sensor reading tricking it into believing there is less air coming in than there actually is. Therefore leaning out the car.

There was an article a while back regarding E30 BMW's where some mad scientist actually flow benched an e30 BMW intake and found that the stock intake with BMW paper filter flowed better than most drop ins.

Paper isn't as restrictive as many think. Think of how much surface area there is in the paper pleats. Unfold the paper and you will get a very large piece of filter element.

Whereas most foam intakes are not pleated and must flow the area of the size of the filter itself.

As a hypothetical example: Paper may be 5x more restrictive but if it is pleated it may have 10x more surface area. Resulting in a theoretical flow capability of 2x a non pleated foam filter.

Of course I have never tested the flow capability of a stock Mitsubishi filter, but at this point the benefit of a drop in filter on a TUNED car has not been proven to me.

 

Who said anything about it being a hassle?

 

Spend a few minutes to read through all the posts with questions related to filters and intakes and strange behavior with the AP. Replacing a $20 air filter every 20K miles seems much less hassle to me than the much more expensive cone filters or filters you have to clean, oil etc. The only folks that claim extra power with drop in filters or intakes (when combined with a tune) are the ones selling them.

 

^^ That's why Cobb has a stock filter map and a HKS filter map etc. The different amounts of air flow are addressed in the different maps.

 

I think it's more the way the airflow through the filter or intake might alter how the MAF interprets the airflow rather than it allowing more airflow per se. I agree with the poster above, though, who mentions that the between air filters after a tune is pretty much negligible. This holds until the stock intake system becomes a restriction, which IIRC, is near 400 whp (well beyond Stage II).