Is it worth putting a catback exhaust system and 4-1 headers on my 2001 ford focus?

I need to replace my stock exhaust system on my 2001 ford focus ZTS DOHC Zetec-E and want to know the pros and cons if I install a catback exhaust system and 4-1 headers or what else I should replace my exhaust system with, I can do it myself so ill only pay for parts. Is there a performance gain? What're the drawbacks?

Doubt you'll pick-up much HP, as the factory system isn't that bad. The sound will be better. So it's a value judgement, which only you can answer. Are you happy with the car? Good Shape? Plan to keep it a couple more years?

It will make a bit more noise, but that's about it. You won't get enough extra HP to actually notice.

Some people associate a loud car with a fast car… Not the same thing.

Hi No if this was being done to a car with less mileage on it or a much newer where the benefits would be felt then maybe, but really a 14 year old ford waste of time and effort.

There are different headers on the market and some are better than others. If you install a poorly designed header, you'll actually end up losing power, not gaining it.

But if it is a good design with equal length runners and a properly designed collector, you will gain some power. How much that will be will depend on the rest of the vehicle's modifications. If it is just the exhaust alone, it is not something that will be felt by your but dyno. If you already have other modifications and the exhaust is now the choke point, opening up the exhaust flow will have a more significant impact on performance numbers.

The big drawback is the expense. A good exhaust system is not cheap and you will be installing it on a 14-15 year old car.