Hi guys

Ive got a 02 sti with a green panel filter and cat back stainless sytem. If i was to replace the 2nd cat with a decat pipe will i notice a big difference. I also have a walbro fuel pump that i havnt fitted,,would it be neccesery for this to be fitted at same time as the decat.

Excuse my lack of knowledge but this is still all new to me...

cheers

 

Replacing the 2nd cat would probably give you another 5-10bhp which you wouldn't really notice in normal driving. It was one of the first things I did to my WRX and it only made a slight difference.

If you then had a remap, you could then see noticeable gains especially with the filter and other exhaust mods.

The Walbro pump is only supposedly needed above 300bhp, so you wouldn't have to fit it until you had it mapped.

 

Better off replacing the up od downpipe cats, although its harder/dearer, you'll get more bang for your buck!

Simon

 

If you do this you will have to have the car remapped also, approx 650 quid

Tony

 

its just i have the second decat in the house, i might aswell put it on providing it causes no problems to the car.
I will eventually be getting it mapped etc but at the minute money is a bit tight.