gutting the pre-cats

[TIMSRS]

Has anybody removed the pre-cats on the standard downpipe?
My car has a stage 1 with a miltek system (cat-back)
What advantages do you get.

[BigMo]

10bhp possibly more. More V8 noise

[Cornishmoocher]

I have removed both...........510 bhp 560ftlb Have a look on youbtube.......

[ataRS6]

I have completly removed mine and replaced with 3" miltek down pipes the V8 sound is the best and you get quicker spool up feels much more responsive

[tartan_rob]

MRC did mine, on std exhaust otherwise though.

[TIMSRS]

Did you notice any advantage when they did it ???????

[tartan_rob]

I had it done at the same time as remap and new torque convertor. When I had this done on my B5 S4 it was a standalone piece of work. The turbo's spooled easier, held boost longer and released some extra noise. Underbonnet temps should be lower too.

[S2tuner]

Exhaust gas temps will be lower too with gutted precats, so all in all, less stresses on your turbos in the long run

[Cornishmoocher]

if you gut the cats be sure to get the map to go with it, otherwise you will get an EM warning- cat below efficiency bank 1 & 2.......

[TIMSRS]

Yep this is what Grizz has told me. he is looking into a map for the stage 1 that removes the EML and cuts out the cat signals.