What mods should i do to my 535i to get max potential out of it?

[petedarwin]

Hey all! i recently bought an e39 535i 1999 bmw completely stock and am wondering what sorta mods i can do to it to get the most out of it. mates have suggested new exhaust system, air intake and maybe even a supercharger. just wondering if anyone else out there with a little more knowledge on these cars has any tips? thanks for you time

Pete

[Scotty89]

If you're even considering a supercharger, it sounds like you're after some serious performance/power increases...

In that case I would say, don't do it. It's alot more effort than it sounds, and to have it done properly can cost a fortune.

Forced induction is the most effective way to increase power, and it will cost thousands upon thousands of dollars.

Without going forced induction you can work your engine to gain more power through a better flowing intake/exhaust, stroking/boring the cylinders and reinforcing the internal components of your engine with forged parts etc (more important in the case of forced induction).

If you get this far, a computer re-map or a new tune to have it run with more precise timing will gain some additional power/torque too, though you might have to run higher octane fuel after this.

None of it will be really cheap though. Power is expensive - when you look at it that way, an e39 M5 probably is pretty good value for ~300kw for roughly $45-60k


I would suggest looking at other e39 5 series projects that have been posted on online forums, and have a look at the power figures they are getting out of their cars compared to the money they have put in. That will give you a better idea on the costs.

[petedarwin]

hey scotty, thanks heaps for the advice mate, i'll take it on board. yeah think i might start with a decent exhaust. is it worth going all out and getting 2.5in the whole way through with headers and cat back etc, any ideas on how much it would increase the power by? cheers

[Scotty89]

If you get a whole new system (from the exhaust ports on the engine block right through to the muffler tip), the results will only be marginal. Don't expect it to drive like a race car At the very most, you might be able to gain 10% more power if you upgrade the intake/filter as well.

Basically these two upgrades will go hand in hand, as they allow better airflow into and out of the engine. It is a trade off as you shift the bulk of your torque curve up to higher rpm, which is how the higher power results. It means less low end torque, and more higher up. So it should give more pulling in the higher rpm register.

With that said, its probably one of the first/most common upgrades. The most noticable improvement will be the the sound. In most cases it will give you a much more aggressive sounding note, if you get a nice system. IMO the standard exhausts I've heard on e36's/e39's are pretty lacking - I know mine is for sure You should get a nice growl/purr from a new exhaust.