Decat

[is200jim]

hey guys, has anyone had any problems with decats?? engine warning lights etc? ius there much of a power gain? if it makes any difference my car is 02 plate

please advise

regards

jim

[Jimxms]

Could be wrong but I'm pretty sure there is an o2 sensor behind the cat on the IS200 which will give you a warning light. Also modern cats are much less restrictive than on older cars so the benefits are likely to be negligible. Especially compared to the disadvantages like MOT failure, black soot on your bumper, smelly exhaust...etc :)

[sparkystav]

If you remove the cat there is a O2 sensor behind the cat thats only function is to check if the cat works correctly.

You'll need an O2 simulator or you get an ecu light up. I can supply a suitable O2 simulator and full wiring instructions.

PM me and i'll help out

Does free up the gases though.

[is200jim]

is it noticable gain though? have got cat back system already on the car and tht is rather free flowing, dont want to risk loosing power?

[ormi]

is it noticable gain though? have got cat back system already on the car and tht is rather free flowing, dont want to risk loosing power?

also just coz you remove the cat doesnt mean it'll be a mot failure...

[jeffrosie]

What about if the manifold and associated cats were left inplace and the secondary cat was removed. That should not throw any codes from the ECU, and free up some gas flow.

[ormi]

What about if the manifold and associated cats were left inplace and the secondary cat was removed. That should not throw any codes from the ECU, and free up some gas flow.

you'd be better removing the pre cats and leaving the main cat...the pre cats are more restrictive than the main cat...

(i removed mine and noticed a diff straight away)

[is200jim]

What about if the manifold and associated cats were left inplace and the secondary cat was removed. That should not throw any codes from the ECU, and free up some gas flow.

you'd be better removing the pre cats and leaving the main cat...the pre cats are more restrictive than the main cat...

(i removed mine and noticed a diff straight away)

how do i go about removing the pre cats?? would that mean replacing the standard manifold?!

[DriftKid]

I have an MR2 roadster as wel which has precats, just banged them out and used a blower to get rid of any remaining material dust...helped free up a bit of breathing and a noticeable torque gain! I'm guessing it's probably the same on the IS200/IS300!

As for decat yes another gain is felt and heard but the chances of failling an MOT on emissions are higher but it is possible to still pass (if your lucky).

[ormi]

it would be very hard if not impossible to bang the pre cats out no way of getting to them...

remove the manifold take it to an exhaust makers and tell them to remove the precats they will prob cut them out and weld in straight pipes..

then keep the main cat and you'll have no probs(the standard cat isn't that restrictive...)

[fjcfarrar]

What about if the manifold and associated cats were left inplace and the secondary cat was removed. That should not throw any codes from the ECU, and free up some gas flow.

you'd be better removing the pre cats and leaving the main cat...the pre cats are more restrictive than the main cat...

(i removed mine and noticed a diff straight away)

how do i go about removing the pre cats?? would that mean replacing the standard manifold?!

Complete Decat could increase power & performance very slightly by reducing the already negligible gas-flow restriction. Much the same effect as reducing weight by emptying the windscreen washer. The biggest change is a slightly go-faster exhaust sound.