r

hi all, help needed please!
i own a sti7 uk.trying to de cat the exhaust,not sure what to do really! can any one tell me how many cats i have in my exhaust? is the exhaust layout similar to classic? ie can i just remove the one lower down the exhaust towards the back box and fit a back box,or do i have to remove all sections? i should have said i am not that interested in loads more horses!,but some would not be wasted!,just want to realease some more volume!i dont just want to fit a back box though.hope this makes some sence!please help!ps.trust induction filter is already on!

Brun

Change whatever bits you want.
Bacbox
centre section
downpipe
up pipe.

As i own a classic i'm not 100% sure about the STi7. I do believe however, you will have a cat in the up pipe, one in the downpipe and one in the centre section.

r

ta i will!

john banks

Have a search, some decat systems will make your car detonate badly, even some sports cat systems will.

r

ok cheers john

r

bttt

stevejohnson511

Sti7 has two cats one in the down pipe and one in the centre.Removing the downpipe cat will give boost spikes and will need either a new restrictor or a re map to cure.
Steve

r

crash bang whollop!

Pete Croney

r

The standard car spikes too, but once you fit a free flowing system, the maps in the ecu cannot keep up with the improved spool up of the turbo and the boost overshoots its target.

Full boost will be achieved at 3000-3200 rpm, instead of 4000 rpm with the original exhaust.

The 7 has a cat in the downpipe and one in the forward centre section.

Most manufacturers will supply the revised restrictor with their exhaust system, which completely cures the boost spiking issue.

r

thanks pete! very interesting.i will look into it a bit more,i think