Exhaust upgrade

Post Fri Sep 04, 2015 7:14 pm

Can someone please advice on this.
I currently have 323 ljet which is running stock exhaust. I have got a friend who has passed me his m3 sport evo exhaust. Entire system minus the extractors.

Question:
Is this worthy upgrade?
Will it be direct fit?

Looking for some advice before i pursue this.

Thanks guys.

Post Fri Sep 04, 2015 9:23 pm

Exhausts are far more complex than just "bigger or smaller". It's about minimising backpressure and maximising scavenging.

What I'm trying to say is, every engine will have it's own optimum exhaust set-up and just sticking a different exhaust on isn't likely to suddenly gain you noticeable horsepower. There are exceptions where an engine may have a restrictive exhaust as standard due to emission regs or something, and simply getting a more free-flowing one will yield results, but it is far more complex than that. A bigger pipe will allow more gas through but at a slower rate, whereas a smaller pipe will allow less gas through at a quicker rate. It's about finding the balance for that engine.

In this case I would imagine that exhaust has gone through many many hours of R&D to be optimum for that engines' power band. Sticking it on a 323 engine which produces different power in a different rev range, let alone has a different number of cylinders, is no guarantee of performance. It could just as easily reduce performance.

Post Sat Sep 05, 2015 5:43 pm

Thanks for the feedback mate.
Let me change the question then. What would you reccomend as an upgrade for my 323 interms of exhaust. The car is as stock as it gets when it comes to engine. And its a manual transmission.

Post Sat Sep 05, 2015 5:51 pm

The M3 exhaust should fit under the 323i, but it won't mate up to the 323i downpipes so some bodgery will be needed to get it to fit.

Post Sat Sep 05, 2015 8:30 pm

roguegenius wrote:Thanks for the feedback mate.
Let me change the question then. What would you reccomend as an upgrade for my 323 interms of exhaust. The car is as stock as it gets when it comes to engine. And its a manual transmission.

Are you planning on doing any modifications to the engine? Always handy to plan long term.

Post Sun Sep 06, 2015 4:15 pm

If you have a good genuine M3 Sport Evolution exhaust , you are much better off selling it ,as it will not fit your car without butchering and it is specific to a Sport Evolution and worth a lot of money !
Obviously if the alleged sport Evolution exhaust is some worthless Scorpion scrap, get cutting !