is that the cat in the down pipe or the 1 in the centre section under the gearbox

 

davers, assuming you plugs, lambda sensor and coilapcks/HT leads are fine, then a Classic shouid get through the MOT emissions tests with just a working catted downpipe only (not sure about the centre cat on it's own i.e. when a decat d/p is on, though ).

 

I was hoping to go down that road aswell fit a de cat downpipe and swap the centre section for a catted one at MOT time.
Wonder if that would work i guess you would have to get it very very hot to pass due to the location?

 

hi yeah i welded one in under the propshaft where the floor is open it dont have to be a cat 4 a scoob . just make sure its small enough to fit.

 

Yeah, I reckon that'll work...

When Paul at Zen eventually got mine through (needed Lambda and 2 new coilpacks ), he went for a 10-15min hoon to get the cat extremely hot... and it passed the 1st Fast Idle Test on the CO2 really easily i.e. the CO2 was into the hundreths of a percent, and not mere tenths!

 

cheers mate. yeah just gonna bin off the centre and keep the one in the downpipe.

still cant decide on a number of exhausts though, at 1st i wanted a 6x4 magnex but now ive been temped by a blitz nur spec.

 

replacing the centre cat does little for performance, the real beans are in the downpipe cat
Even then it will need mapping for to release all the potential horses in there.

My local tuner has a specially made centre pipe with 2 cats welded into it for MOT time.

 

I have my type R decatted at downpipe..didnt notice much difference in power tbh.
Roughly how much would a remap cost to get the most outta the decat?

Cheers
Ryan

 

I had a 93 wrx a 95 wrx and now a 97sti v3, all have only had one cat. All had original exhausts when i bought them.

 

what and he just sticks it on for your MOT?

see i wouldnt mind taking both off, but taking the one in the downpipe off just causes more hassle and knowing me wouldnt sort it in time for MOT