Balancing Weight

[DonovanPorter]

spoke with mechanic a while ago he recons that the E46's have a balancing weight in the sump , wich they remove and gives the car +- 5 - 10 kw more and makes the motor rev better. He had one of these balancing weights with him at the time , its a seriously heavy piece of equipment that has two weights that are cylindrical and lay parallel to each other in a solid steel case these weights are connected by one sprocket/gear . This is bolted in side the the sump and is connected to the cranck by another sprocket/gear.
So i want to know how does this balancing weight work and what role does it play , and would it be adviseable to remove it ?

 

[Coisman]

imp:
Ask Clutchplate, he is busy rebuilding a 330i E46 engine.
http://www.bmwfanatics.co.za/showthread.php?tid=8482

 

[DonovanPorter]

thanks Coisman will do

 

[Coisman]

imp:
Get him to answer your question in here, so ALL others can know.
:thumb:

 

[DonovanPorter]

will do

 

[applehero]

I have limited knowledge about this. Is it not specifically the four cylinder diesel units he's refering to? From what I've heard, the good thing about an inline 6 is that it is balanced as it is...

I'd say keep it, if there wasn't a reason for it being there BMW wouldn't have gone through the cost of developing it! :thumbsup:

 

[Coisman]

I have limited knowledge about this. Is it not specifically the four cylinder diesel units he's refering to? From what I've heard, the good thing about an inline 6 is that it is balanced as it is...

I'd say keep it, if there wasn't a reason for it being there BMW wouldn't have gone through the cost of developing it! :thumbsup:

imp:
I agree about the 6's, balanced by itself, only the inline models I think. :thinking:
Find out more about this weight thing. Maybe it's like the cats, there but the car don't really need them. :dunno:
I tried google...but no luck.

 

[zaleonardz]

Of course I am an utter idiot on the subject, but I disagree with removing the balancing weight.

I am actually paying somebody to balance my pontiac motor.

Think about it, the more balanced the crank is in relation to cylinder friction and stuff, the less chance of knocking, when the engine picks up there is knocking, it adapts itself to run easier, thus decreasing perforance.

So while I see that removing the weights will make the crank lighter, thus less transfer loss, and it could possibly give you 10kw, its there to keep the motor smooth, and ensure long life by the motor not eating itself from the inside.

Another thought, if you need to remove the serious balancing weight, do you think that the motor will be balanced enough without it.

I would skip this mod, but then again, I dont know much, would love to hear from the other guys

 

[DonovanPorter]

i fully agree if its there its therefor a reason will wait to see what the guys have to say , i have pm'd clutchplate , so will wait for his views

 

[Sankekur]

My opinion would be that the balancing weight would be there for a reason, and the best thing to do would be to leave it as it is.

 

[DonovanPorter]

From my Haynes manual

"The M43TU 4 cylinder engines are equipt with balancer shafts to smooth out any vibration, these contra rotating shafts are gear driven from the crankshaft sprocket and are integral with the oil pump."

With that it seems that this is an integral part of the motor , so bad idea to remove it.....

 

[Truvalu]

we just like to fix things that are not broken.....

 

[rick540]

Come take a drive in my 4 cylinder Merc if you want to feel what it's like without balancing weights. Bring a kidney belt.

Why do guys always want to hack holes in well designed air boxes with Helmholtz resonators, unplug exhaust flaps, remove parts remove balancers add aluminium flywheels?

Yes some of these will improve power, or screw up NVH balance, but most will shorten the life of the engine.

Every time these poor engineers add stuff to a BMW that for example a Golf doesn't have, all the modders want to go remove it. If you want your BMW to go like a zooped up golf and sound like it to, then go ahead remove stuff it's your car.

I personally like BMW because they took the time to add all these thoughtfull enineering features.

 

[Hellas]

Though I don't believe you on the Merc/kidney belt story Rick. Those Germans next door to our factory sure know a thing or two about cars too :drool:

 

[rick540]

Ok maybe not kidney belt lol but not quite as smooth as an E46 though, tough as nails I like and respect the thing for that.

My brother once rented a Cherry when he visited, I took it for a drive.

OMG, now that was awfull, cubby dropped open from the vibration everytime it passed 3000 rpm

 

[hennie]

removing that wont ad kw to what the motor makes that you cant change by removing weight from engine components
if they claim a 10kw increase it was always in the motor now its not being used by the component removed
what you do get is more kw going to the wheels as the kw using goodies on the motor is not there to claim their share

 

[moranor@axis]

straight-6, V12 and Boxer engines have natural dynamic balance it was the main reason why i only wanted a 6 cylinder dont know why but i love it when things have an elegant solution instead of having to fight and add things onto something to make it work properly...