Balance Shaft Delete

[Preloader]

Curious, and hoped to start an educated discussion about BSD. Most 4-bangers have a balance shaft to reduce vibrations from unbalanced stroke sequence. This shaft can weigh 25+lbs in some motors, and in search of higher rev horsepower, it can be beneficial to delete it.

The downside is vibration, which I don't mind, but is some kind of kit necessary to do it? And how involved it it?

 

[Stew]

I don't see one looking at an exploded view of the 1.4L

 

[Eric Smit]

it's a lot of rattles, could be detrimental, and if we have one, it's relatively involved. pull the motor (maybe optional) pull the head, delete the balance shaft. there are kits out, but not for our car.

for example

 

[RS Turbo]

There is no balance shaft in this engine.

 

[ThatTmoGuy]

Balance shafts are usually only found in larger (2.0+) four bangers. I doubt we have one.

 

[Preloader]

Oh well. I know Vince made a reference to the BSD in regards to hi-revving a 1.4T, but maybe it was more of a generalized statement.

 

[Gsrdude]

Been removing them in 4G63 Land for years. There is more conflicting information then one could possibly read in a day around this. AMS uses machined shafts in their builds. Some turn them down themselves on a lathe.

Buschur Racing and alike use the old OEM Stubby shafts without issue

You can read the AMS's logic here

AMS 4G63 Race Balance Shaft Eliminator Kit


Countless folks have used the Old Stubby shafts with no issues for decades now.

 

[Dave@ddmworks]

Curious, and hoped to start an educated discussion about BSD. Most 4-bangers have a balance shaft to reduce vibrations from unbalanced stroke sequence. This shaft can weigh 25+lbs in some motors, and in search of higher rev horsepower, it can be beneficial to delete it.

The downside is vibration, which I don't mind, but is some kind of kit necessary to do it? And how involved it it?

Also, along with the other points made here, the reason that you get rid of the balance shafts when spinning the engine to higher RPM ranges, is not because of the weight of the balance shafts, but because of the very high bearing loads that the balance shafts start to create at higher engine speeds. Since the balance shafts do not have their center of mass along the rotational axis, as they spin they place a load onto the bearings that they spin in. As you start to spin those shafts very fast, the force against the bearings can get very high and create a lot of heat and also take a good amount of power from the engine output. The 2.0L LNF balance shafts are a good example of this, since the neutral balance shafts are actually heavier then the stock balance shafts, but they are balanced and therefore create very little bearing loads at higher RPM's.

Hope that helps,
Dave

 

[Preloader]

Dave, can you confirm that the 1.4L does not have one.

 

[Dave@ddmworks]

Dave, can you confirm that the 1.4L does not have one.

From everything I have seen the 1.4L does not have balance shafts. I looked at the GM exploded parts view, did a search for balance shafts with our parts source and didn't see anything. We have not had our engine apart here yet though, but unless someone can point out a part number or a picture showing anything that is acting like a balance shaft, I don't see any.

Also, as ThatTmoGuy pointed out, usually they are only on engine over 2.0L in displacement.

 

[ChrisJ]

I should put "balance shaft delete" in my sig for the sonic and cruze.

Easiest mod I ever did!