There seems to be conflicting advice re fitting a decat downpipe as some have found no problems and other have had problems with overboost, etc.

I have a 1994 WRX JDM running on the OEM ecu with octane booster and other than a TSL decat centre pipe/Group N back box/STi Group N panel filter have no other mods and have had no running problems in two plus years ownership.

I am now considering a TSL downpipe but will also fit a knock link and boost gauge.

There seems to be conflicting advice whether the ecu needs remapping but in any case this would apply to an after market ecu that can be remapped rather than the OEM one.

Any JDM users out there with original ecu's/octane booster got any experience of changing to a decat downpipe ?.

 

hey there

i have a 93 wrx import with hks induction, hks 3inch d/pipe, scoobyworld centre & backbox - so no cats!
I have a Z4 ecu which i had a scooby chip put in by scott t. but he doesnt do them anymore, & it runs on optimax alone without a prob but i still put octane booster in every now an again.

Not a single prob with any of the running, runs sweet (touch wood!)

Hope that hepls