04 jdm impreza de-cat
 

hello in a couple of weeks im going to get ma scoob serviced and going to buy a link pipe de-cat but also thinking of removing resonator in the mid-pipe out whats the benefits of doing this ?:thumb:


many thanks usmann

Are you asking benfit of replacing centre resonated section? If so, no benefit in performance/spool up terms, but it does release a bit more noise. I did mine (have sportscat d/p).

dnc

Well as long as you get it remapped afterwards you will be ok ;)

Tony:)

thanks tony subaru4you are saying that i wouldnt need to remap it ?so i do have to remap it tony ?

usmann

I have a 3" rcm decat downpipe for twinscroll if your interested. Will prob need welding to fit tho to the rest of your system. Pretty much brand new. Only want £50 for it.

Hmm remind me not to go there :lol1:
Put it this way, if you dont remap it, you will be left with knackered pistons due to overboosting and det, or if you do remap it then you will be ok ;)

Tony:D

thanks tony

im guessing these engines are very sensitive to exhaust back-pressure. freeing the back pressure the factory set wastegate should still maintain some type of regulation?

ecu have no fuel cut when it gets out of its MAP/MAF sensor max resolution?

EJ20 have knock sensor FB?

I have a independent wideband NTK one, will possibly get it de-catted and monitor the AFRs on full boost.

from what your saying either they are heavily restricted back-pressure wise or the boost control wastegate is sized for nothing above factory boost?


many thanks

they gain power when mapped for exhaust changes, or even mapped on original exhaust..

fuel cut is at a set boost level

they have knock sensor and complicated knock control.. but it has to see knock before it pulls timing to stop the knock.

It is not just AFR's.. it will most likely be mega rich on boost.. you will gain lots having fuelling and ignition setup and extra boost added

Simon