Was at Rocket Ralley Racing in Squamish, B.C. Canada and they had a 2008 gsr. The guy had a short air ram intake and the results on the dyno were terrible than the stock one.He told me not to bring my car to him unless I only had a drop in k&n filter.I saw the dyno sheet for myself and the results were off by about 10 or so whp.He said it had something to do with the hood design and the ram design of the stock air box works quite well.
These guys really know what they are doing when it comes to these Subaru's and
just recently the evo x. They also do dyno's,reflashes and just about everything else .
Onur and Pat you guys rock.
Rocket Ralley Racing
9-38927 Queens Way
Squamish,British Columbia
V8B0K9
www.rocketralley.com

 

I lost HP with a K and N and also lost HP when i straight pulled out the stock filter and ran it with nothing. I have a tune though, stock it makes power only via leaning.

 

The best results were with the stock one though,but we haven't tried the k&n with my set up yet.

 

Welcome to the Evo game. Intakes have been a big flop for a long time for many people. The factory airbox with a K&N filter works too well. And as with changing any amount of airflow, you need a tune.

 

That are the tuners words right out of his mouth.

 

Do a search, the WORKS drop filter appears to be the best, but also the most. Next is HKS and K&N not in the specific order. Best of luck. I believe most drop ins will get you at a minimum 10 HP.

 

That sounds about right. I purchased the APG fenderwell intake and now looking to sell for one of those other drop in jobs.

 

Intakes and filters on a TUNED car appear to lose HP.

On a completely stock car they appear to add HP ONLY because they lean out the AFR.

So you can see when you tune the AFR via the ecu there almost is no need for a filter at all.

This is just my findings though via my dyno charts.

 

I saw that one but wasn't sure of their track record so went with the good old dependable K&N.

 

Just thought I put that out there before anyone goes out like I did and spend 250 or 300 dollars on something they could have for 60 bucks.

 

I am curious as to what power level this holds true up to/is that a factor. Do any of the vendors have any dyno numbers with regards to this on a car that is making 350+whp?