M54 Madness, the remix

[Cardude]

I would assemble the motor, trans, subframe and everything all together and install it all from the bottom if you have the means to do it this way. Im quoting the post that Jordan did showing how his all went it in

Pretty awesome build, I like the fact that you used MS3. My buddy is running that on his wifes Turbo Cabriolet and its so easy.

Random question, what is that condenser that you are using?

[hoveringuy]

Why not Turner or the like Shorty headers? They seem to add a massive amount of power to the low end in comparison to the stock M52 exhaust manifolds.
And why not SS style long tubes? They are proven power gainers...

My goal isn't necessarily to make maximum power. I'll be using the M52 manifold because I think they're actually somewhat effective and because they're quiet and also great for keeping the engine bay (and cabin..) cooler. Plus they're light and easy to work around.

I really did love my S50b32 headers, the sound was divine and the power was great, my only issue with them was that the flange hung a little low and I just didn't have the motivation to deal with re-working them to fit better.

[TheAxiom]

My goal isn't necessarily to make maximum power. I'll be using the M52 manifold because I think they're actually somewhat effective and because they're quiet and also great for keeping the engine bay (and cabin..) cooler. Plus they're light and easy to work around.

I really did love my S50b32 headers, the sound was divine and the power was great, my only issue with them was that the flange hung a little low and I just didn't have the motivation to deal with re-working them to fit better.

You just described Ebay headers. From my expereince ( 2 different M52tu with headers) great fit, great power and literally no downsides. In DD with a stock exhaust, the car was quiet and sounded stock.

[hoveringuy]

New exhaust is fitted and, wow, what a difference! Went from being loud and rough to smooth and quiet. Revs crisply to redline without all kinds of annoying harmonics. My 0-60 is 70% more comfortable. I also feel like I've recovered some of my torque.

VANOS seals and cam timing is next...

[TheAxiom]

That exhaust is so backwards, I don't know what to tell you - It's compromised in all the wrong areas.

The SS replica exhaust primaries were far too large, and the same with the secondaries - not to mention the exhaust merger is far too close.

The second exhaust is better, but still suffers from the same issues. The primary tubes are too short, the merger is too close but the diameter is better suited for scavenging.

If you're happy, that's great, I'm just saying there is a LOT left on the table with that exhaust.

[mike25]

The second exhaust is a standard BMW header, so I doubt it is as hopelessly compromised and leaving so much on the table as you suggest..........?
It will be a compromise for sure, but a well optimised one for a DD.

[digger]

the OEM manifolds do not scavenge anywhere near what a proper header can and this hurts torque more than anything. its always a compromise though

[hoveringuy]

I think he meant the original exhaust was compromised in so many ways, and he's right.

The OBD2 headers aren't the best, but they're not bad, either. The car is much more fun to drive, at least. it's actually a blast and much more fun to wind-out than it ever was.

I'll take it back offline this week to do the cam timing and VANOS seals, plus alternator bearings and some other little things.

The exhaust upgrade path is TMS shorty headers or similar. Now that I have the stock headers lots of things will fit.

[MrBurgundy]

Awesome build.

curious to see what this thing puts out once everything is sorted.

Sub'd

[digger]

I think he meant the original exhaust was compromised in so many ways, and he's right.

The OBD2 headers aren't the best, but they're not bad, either. The car is much more fun to drive, at least. it's actually a blast and much more fun to wind-out than it ever was.

I'll take it back offline this week to do the cam timing and VANOS seals, plus alternator bearings and some other little things.

The exhaust upgrade path is TMS shorty headers or similar. Now that I have the stock headers lots of things will fit.

are there no longer tube options?

[Jaker]

I'm going from the Raceland shorties with a custom made merge into a single 3" exhaust on my 3.0 build to a custom made Burns collector header. We'll see how big of a difference it makes. I'm hoping for at least 10whp with a healthy boost in midrange torque.

[TheAxiom]

are there no longer tube options?

He had Euro SS replicas from the looks of it - they were never meant for the small M54 exhaust port. But there are plenty of long tube options, specifically from Bimmer brakes. The problem with the OEM manifolds is scavaging, which they don't do too much of. They are better than what he had before, but a set of long tubes would work better - or even something like the AA track pipe would work better. I saw a dyno of one posted by James Clay of Bimmerworld where his trackpipe gained something like 10whp over the whole range.

I'm going from the Raceland shorties with a custom made merge into a single 3" exhaust on my 3.0 build to a custom made Burns collector header. We'll see how big of a difference it makes. I'm hoping for at least 10whp with a healthy boost in midrange torque.

As long as the primary tube sizes aren't too large, it should work. By why shorties over long tubes?

[Jaker]

As long as the primary tube sizes aren't too large, it should work. By why shorties over long tubes?

The new ones will have small tube stepped longer primaries. I originally went with the shorties because the car is an autocross car and I value area to the left of the dyno sheet over the right. Didn't stop me from getting 270whp and 240 ft/lbs of torque though.

[digger]

The new ones will have small tube stepped longer primaries. I originally went with the shorties because the car is an autocross car and I value area to the left of the dyno sheet over the right. Didn't stop me from getting 270whp and 240 ft/lbs of torque though.

shorty headers dont make more bottom end than a long tube header when implemented correctly.

Most shorty headers are shorter enough to be never in tune as you dont reach an rpm high enough or if they are intune it is at a higher harmonic and provides a weaker response to that of a header sized correclty, they are mostly just a high flow manifold that sometimes look pretty.

[nando]

The new ones will have small tube stepped longer primaries. I originally went with the shorties because the car is an autocross car and I value area to the left of the dyno sheet over the right. Didn't stop me from getting 270whp and 240 ft/lbs of torque though.

270whp and 240 ft/lbs of torque from an M54? I don't believe that, but I'd love to see the dyno sheets to prove me wrong. :)