Conversion BMW E46 330i Touring with our flywheel article 639

Our customer Leo has installed our flywheel article 639 for the M52/M54 engine on his BMW E46 330i Touring.

He wrote us a great blog - many thanks for that :)

Many people know it.....

You drive a somewhat older model of the BMW 3 Series, whether in everyday life, on nice sunny days or perhaps even in motorsport.

In our case, it's an E46 330i Touring that rolled off the production line in 2001.

Of course, after 20-30 years, minor repairs here and there are inevitable and even the otherwise quite robust engines of the fun factor class M52/M54 have their aches and pains from time to time.

The big enemies are, as almost always, the odometer, corrosion and the ravages of time. This means that at some point, components that have already been replaced for the third time in another vehicle's life will be worn out.

One example of this is the clutch. 200,000 kilometres and more down, it slips, it vibrates when starting off, gears are difficult or impossible to engage, the only thing that moves when loading up is the rev counter needle. The day is over.

"So what, we'll just replace it", some people would shout in between. Basically, it's not a worrying repair for this model, a mid-range car with a straight-six engine and rear-wheel drive.

So, no more talk, exhaust system down, cardan shaft flanged off, a few more screws and the gearbox (right) is remov

Now we can already see the clutch pack. However, to see whether the lining of the friction disc (also known as the driving disc) or the pressure plate with its diaphragm spring system has given up the ghost, the automatic unit must be removed from the flywheel.

"Well then, 6 mm hex key here and out with the few screws!"

When removing the automatic clutch (left), we notice that the flywheel (right) already has considerable radial play and the overall condition, rated as poor, leaves a lot to be desired. So we postpone the completion of the repair and start looking for a new flywheel

At this point, motorsport enthusiasts, but also the more sporty Sunday rider, often ask themselves the question:

"Should I convert to a single mass flywheel right now?"

At least it won't break and it increases the driving pleasure and the responsiveness of the engine many times over due to the lower weight.

So far, correct, but now comes the somewhat more complex part of this project.

The M52/M54 engine range was (unfortunately) never supplied with an EMS ex works. This means that there are few alternatives to high-quality components, and the risk that original clutch packs will no longer fit remains.

I faced exactly the same problem. Several times.

Now there is a flywheel from Epytec. I read the description and asked customer service whether the original clutch can still be used. The answer, "...if it doesn't fit and there are no installation marks (driving marks), I can send it back."

The price was very fair compared to other manufacturers (where the original clutch, which is readily available here, could not be used).

Ordered. Earliest possible delivery date - 30.08.23 *grumble* 08.07.23 - flywheel arrives. *joy* *unpacking*

At approx. 6kg, the EMS is about 8kg lighter than the OE DMF. The workmanship leaves nothing to be desired.

Schraubensatz für Schwungrad und Druckplatte liegen mit bei (Festigkeitsangabe 12.9).

The sensation of the day and ultimately the reason for writing this report:

The original clutch fits! *HEUREKA*

The fitting bolts of the EMS correspond to the bolt circle of the original pressure plate.

This achievement alone seems to be an insurmountable obstacle for other manufacturers

The height of the distances, with the pressure plate in place but not bolted (with friction disc in between), are almost identical. The difference in the overall height of the two flywheels (EMS vs. DMS) is only 4.0 mm:

This should result in the release bearing travel being 4.0 mm longer, as the automatic clutch is now closer to the crankshaft by this amount than before with a DMF. As I drive the construction myself, I can add here that it is not noticeable in the pedal travel.

There is a supplement to the original clutch:

Various clutch kits are available as accessories from the manufacturers ZF Sachs and LuK.

LuK only offers SAC (Self-adjusting Clutch) clutch kits with visible springs (yellow + radially arranged) and locking piece for the M52/M54 engines.

ZF Sachs only offers XTend Type I sets.

Source: ZF Friedrichshafen AG

The idea behind both systems is to make the clutch more durable through automatic adjustment.

Personally, I prefer the Sachs system (XTend TYPE I), which, however, violates the installation instructions for the assembly process with the clutch housing stop when attached to the EMS.

This housing stop (shown in red in the picture above) can no longer strike due to the bearing ring of the EMS no longer running flat, which means that the correct resetting of the adjustment mechanism can no longer be guaranteed. The LuK clutch kits with the SAC system are therefore more suitable here.

It is also important to mention that the clutch kits, which according to LuK and Sachs fit models "up to 02/2003" (regardless of whether 228mm or 240mm), include a 10-tooth friction disc.

This only fits the 5-speed gearboxes S5D-250G and S5D-320Z.

If you are the owner of an E46 325i or 330i (M54) with 6-speed manual gearbox or SMG gearbox, you will need the clutch kit suitable "from 03/2003". This has 22 teeth and therefore fits on the main shaft of the GS6-37BZ (6-speed 330i or 325i transmission).

The E36 models with M52 engines usually also have the S5D-250G gearbox installed, so the 10-tooth disc is also mandatory here.

I always recommend the 240mm clutch kits from the E36 328i, E46 328i and 330i for sporty driving.

5-speed(240mm):

Art-Nr. 3000 970 095 (Sachs)
Art-Nr. 624 2333 00 (LuK)

6-speed(240mm):

Art-Nr. 3000 970 139 (Sachs)
Art-Nr. 624 3158 00 (LuK)

It is quite simply possible to achieve better power transmission of higher torque.

A 228 mm (sometimes also referred to as 230 mm) from the smaller 6-cylinder models (320i-325i) can start to slip after a short time if driven aggressively or with a more powerful engine.

Summary:

Excellent quality, very commendable workmanship, perfect fit leaves nothing to be desired (also as far as the original M52/M54 clutch kits are concerned), very light and the price is fair. However, I do have two shortcomings.

Due to the weight saving, the support for the housing stop required for the Sachs clutch kit is missing.
No hole was drilled for the flywheel. This means that from now on, when working on the timing (timing chain, VANOS), you have to rely on a dial gauge in the first cylinder.

I hope I have been able to answer some questions with this article and perhaps persuade one or two people to install an EMS.