Torque and sports/de-cats

[Justin182]

Been looking for a while about some info on this.

I know sports cats release more bhp top end, and de-cats even more so..... but do they lower torque low down in the rev range ?

Ive always had the impression they do but cant find any confirmation.

 

[Englebert]

You would gain more power than what you would lose in torque, but yes i wouldn't be suprised if you losed some. You wouldn't notice a difference from the little Clio though (apart from the it sounds faster so it is faster mind trick!).

The key is to get a remap, removing the CAT will alter the fueling.

 

[izibizi]

cat is just a restriction in exhaust flow

with decat u gain both in torque and power (marginaly)

 

[Englebert]

Not at all points across the rev range.

Besides, exhaust bore size will affect the optimum amount of back pressure.

 

[Justin182]

Yes.. i thought because there is a decrease in back pressure, the would be a decrease in torque low down in the rev range.

Ive got a sports cat on my 182, and although it really does fly at higher rpm... i definately remember thinking there was a drop in torque till around 3k from the first few minutes of driving with it.

Im just interested as im currently trying to make the clio quieter.... i still find it a bit too "boy racer-ish" for my liking. So might return to std cat.

 

[Neil G]

I've got a sports cat on my 172 and TBH didn't notice a great deal of difference in torque levels....throttle response felt a tad crisper though and does pull better top end.

 

[Dubai182]

I have a decat on my 182 on a standard system and TBH can't really tell the difference except noise and a little better throttle response. What really spiced things up was the Group N ECU.