Upgrades/advice: 2001 e46 323i

[Breeze1]

Hello all,

So quite simply I'm looking for advice regarding my next mods, but with one serious limitation: let's consider that I only have access to stock BMW parts at a scrapyard and M parts are unfortunately scarce. I might buy relatively expensive aftermarket parts later , but at this point I'm a bit on a budget and would like to make the most of BMW's OEM parts.

My current setup:
M52TUB28 engine, M54B30 intake manifold, complete 330I exhaust line from manifold to muffler, CAI, 323i (3.07) diff, OEM sport suspension; soon to come: blueprinted injectors (thanks Chris and RC Injection). A tune is on the way as well, but not before making a few mechanical changes.

Here is a random list of what I've thought about doing:

- 330i camshafts (there is a slight modification involved to fit them into the M52TU, but it should be ok)
- decat: either M52 "non TU" headers without cats or stock exhaust manifold with gutted cats or any other suggestion you might have
- higher flowing MAF sensor (but I have no idea which other BMW engine it could be taken from? like a V8 for e.g.?)

I'm also all for improving the chassis/brakes departments, and I have for example thought about putting my front discs at the rear and some grooved or drilled discs I found at the front. Depending on the asking price I could put drilled at the front and grooved at the back.

Anyway sorry for the long post, basically I'm open to your suggestions guys.

[bmwdirtracer]

Have you heard from RC Injection? They should have been done by now, and called you. If not, give them a call!

[MauiM3Mania]

Thinking this discussions belongs in the E46 sub-forum.....

[Breeze1]

Have you heard from RC Injection? They should have been done by now, and called you. If not, give them a call!

I did yes! They emailed me that they were ready for shipping and they should be on their way right now!

[Breeze1]

Perhaps the next mod should be the driver.

I don't see that as a mod, rather as an ongoing and never ending process that goes along the way with the mods...

[MauiM3Mania]

Is this a DD? Any track, auto-x usage at all?

I'd advise against drilled rotors regardless of where the car will be driven. Drilled rotors are known to develop cracks from the heat cycling.

[Breeze1]

It's a DD, yes. For road usage only, but I would like it to be a bit sharper than it currently is. Not really because it's necessary but because I believe a few things could be done at a reasonable cost to achieve that. Brakes are on my list now. And still open to other suggestions for the engine.

[bmwdirtracer]

I fully agree with MauiM3Mania - drilled rotors are not an upgrade at all. All those little holes are just places for cracking to begin. If you use the brakes hard, they'll be spider-webbed with tiny cracks in short order. (They also cause a humming noise, by the way.)
Slotted rotors don't exhibit the same cracking tendencies, but there doesn't seem to be any real proof that the slotting helps gasses escape, or aids braking in any way.

[Breeze1]

I decided I wouldn't put them on when I read MauiM3Mania's comment on them, yes. The thing with my brakes is that I have replaced them with OEM ones (front discs with front and rear pads) not so long ago and I think that was a bad decision because they don't seem to be as good as the BMW ones. The car feels unstable when braking at high speeds, especially after the 1st and 2nd braking, as if they need to heat up. It either pulls a bit to the left or right side (no consistent pattern), or feels like the back wants to swap sides with the front

The geometry recently done improved things a bit, as well as bleeding the system, but it still doesn't feel right to me. So I'm thinking it might be the brakes themselves, as if they have uneven braking forces or something...

Maybe I'll just swap the pads for OM ones and keep the discs, or put the front discs at the back and get "regular" (non drilled/slotted) but larger OM discs at the front.