De-cat on standard valver exhaust?

[earthworm]

I want to keep my valver looking standard if possible, would i still see a gain in performance if i kept the standard exhaust on and fitted the de-cat? Would there be a noticable gain over the former if i changed the back box too with the de-cat?

Cheers

 

[arj256]

Im running a standard system with a de-cat and i noticed a difference and would say its worth doing considering it dont cost much to get a decat and makes the exhaust sound nicer to
You get a better pull top end but noticed i lost low down torque.

 

[edde]

You'll sea small gain depends on the condition of the cat the car will be more willing to rev though.

 

[jamesy]

thats odd because i have been told the complete opposite now not sure what to thinkLOL

 

[edde]

thats odd because i have been told the complete opposite now not sure what to thinkLOL

You'll see some gain as your removing some restriction from the exhaust system.

 

[Tucks]

Ive run a De-cat on the standard system before.No probs,But on my car it seemed to lose a little response/low down pull & go better up top.This varys though apparently depending on the rest of your exhaust.

 

[earthworm]

Ive run a De-cat on the standard system before.No probs,But on my car it seemed to lose a little response/low down pull & go better up top.This varys though apparently depending on the rest of your exhaust.

So would it be better to change the whole exhaust? When you say its better up top does this mean higher in the rev range or higher in speed?

 

[Tucks]

Yeah sorry I mean higher up the rev range.Seems to go up to the rev limit smoother with the CAT out.
If you want a standard-ish sound you will have to keep the standard system(CAT back)...unless you have a custom Exhaust made and ask them to make it quiet.

 

[u33db]

You'll see a gain yes, it'll be more eager to rev as has been said.

Be careful tho...decat on a std exhaust can blow the packing out of the rear silencer...this will either make it rather loud and a bit more powerful or else worst case feck the thing and restrict the flow.