inlet and outlet system

[Cannondale99]

Hi all.

I'm planning on working on the inlet system and the exhaust system on my car.

Main reason for this, is because I've read somewhere a while back, that on my car, this is very restricted, and there's lots of potential available if worked on....

The car is an E39 5 series, 523i SE.

So, what should I be looking at doing? Do Gruppe M carbon filters really work? Should I have the inlet manifold re-worked? Are stainless steel exhaust manifolds a worthy investment? After reading a lot of posts on here, I'm considering an Eisenmann exhaust system. Am I on the right tracks?

I've no idea where to start. Any help would be great :)

Thanks a lot.

Chris

[peppernick]

To get maximum gain from your exhaust system, you will first need to replace the kats, then you stock manifold. No cheap. Stainless performance rear box will give you slightly more HP but not to the extent of an uprated kat or 6 branch manifold. Your car will sound better though.

However, your M52 2.5L will breath better with a larger throttle body. PM Alpina527, he specialises in modifying throttle bodies.

GruppeM will yield slight power gains but it's the noise we buy them for.

[Cannondale99]

Cool. That's explained things quite well, thanks :)

[CA Automotive UK]

here is a list of what we have done to similar engines , with most cost effective items at the top :

- larger throttle body and Schrick intake manifold ( or modified M50 intake )
- Schrick cams
- remap
- manifolds
- cold air intake
- dekat and exhaust
- pulley set

[alpina527]

However, your M52 2.5L will breath better with a larger throttle body. PM Alpina527, he specialises in modifying throttle bodies.


Thats me!