Will an exhaust leak post cats cause power loss?

[FrayAdjacent]

As I understand the exhaust backpressure issue (dealt with this a bit when I changed out the exhaust on my previous car... replaced headers and catback, and had a high flow cat installed), some is good for N/A engines.

Some backpressure is good for N/A cars, as it helps with low end torque, but can end up reducing high end horsepower. Reducing backpressure can reduce low end torque, but should help with high end horsepower.


Of course, actual changes in actual cars may differ, so it's pretty subjective.

When you say 'lose power', it's also subjective. 'Power' as in low end torque, or 'power' as in peak horsepower could be different things.

[Boxtaboy]

Absolutely. I do recall now, that what I read indicated that with N/A cars, a little back pressure is good for torque, while removing back pressure will probably decrease torque and increase hp up top in the rev range. I believe that with force induced cars, reduced back pressure gives good gains in both torque and hp.

[MNBoxster]

Originally Posted by Boxtaboy

Absolutely. I do recall now, that what I read indicated that with N/A cars, a little back pressure is good for torque, while removing back pressure will probably decrease torque and increase hp up top in the rev range. I believe that with force induced cars, reduced back pressure gives good gains in both torque and hp.

Hi,

Only when On Boost, otherwise, it is an NA car...

Happy Motoring!... Jim'99

[CJ_Boxster]

I wish there was an exhaust which had butterflyu valves which opened at a certain RPM... you know, best of both worlds.