what are the effects of removing the balance shaft? i know it makes your car rumble and ive heard plenty of stories about it.

 

balance shaft?

 

arent those only used on V6/V10s? (odd-number/side V engines)?

 

Balance shafts are more common on inline 4 cylinder engines. Because I4s can never be *fully* balanced, the balance shafts spin in opposite directions, cancelling out most of the vibration inherent in large displacement 4cyl motors. They are also used in some V6s, but the technique is most common in straight engines.

The balance shafts are powered by the engine, so they technically do cost you a few HP (4-8 roughly), so removing them can make your car slightly faster, however you will experience a much rougher ride, and I don't really think it is worth the sacrifice in ride quality just for that.

 

it will make your car vibrate like a chicks 2nd best friend... and most of all void any engine warranty

 

and would be pointless

 

it will destory your engine from shaking it apart. All engines have them. i think an i6 is the closest to a naturally balanced engine.

 

i wouldn't reccomend removing the balance shafts unless you have the motor balanced and blueprinted. the tc motor requires some modification to oil passages to remove the balance shaft. it can be done, i hear the ser guys do it to pick up some power

 

my friend did it on his ser...it made a hell of a difference let me tell you. he had intake, heade,r exhaust, clutch, and removed the balance shaft and he rank 14.4's all day in the 1/4 mile. and he beat sti's on a 75 shot.

 

tat STI is dam slow then cuz they run 13.7 haha

 

STi ran 13.7!?!?!?
getting around .75 too slow

 

Balance shaft removal isn't worth it for the 5 hp you gain. There are many other ways to squeeze out that little bit of hp, without sacrificing the engine's integrity and ride quality.

 

sti's run 13.1 stock. its hard to believe that a ser beat it but i was in the car. it was off a 2nd gear roll my friend pulled on him by a car and a half. remember its also a 75 shot of nitrous thats makes a real BIG difference..

 

races from a roll are dumb.

 

when your racing an STI i hope you dont try off the hole...unless you got something real sick

 

if you want to see the true performance of your car, do it from the hole.

either way this is going OT i'll stop

 

And he would have run a whopping 14.45 most likely with the balance shafts. It isn't worth removing them, and is a pretty horrible idea really.

 

First, allow me to establish some credibility here: A few years back I was responsible for the design engineering of the crankshaft (along with several other components and subsystems) for the Buell Blast mototcycle. I also provided design engineering for several custom racing crankshaft assemblies for V-twin Buell racing bikes (45-degree "V"'s which are extremely difficult to completely balance). Needless to say, I've got some legitimate technical knowledge in this area.

Engine balancing is all about "counteracting" the inertial forces that arise from the "translating" parts (pistons, wrist pins, rings, connecting rods, bearings, etc.). The simplest way to do this is with the counterweight masses you see on the crankshaft.

Only the "purely translating" forces can be compensated by simple crankshaft counterweights. The secondary, or harmonic, vibrations induced by the connecting rods due to their non-symmetrical translating and rotating motion, occur at a frequency that is twice that of the primary imbalance forces. Thus the introduction of the balance shaft, which rotates twice as fast as the crankshaft.

The crankshaft couterweights and balance shafts don't reduce the loading of the moving mass, rather they reduce the resulting imbalance forces from being transmitted to other components and through the motor mounts to the vehicle, people and stuff in the vehicle, etc.

You'll find most (non-automotive) engines have crankshaft counterweight only. So removing balance shafts may not necessarily be fatal. But without knowing exactly why the balance shaft was put there you could jeopardize more than just the "no perceptible engine vibration" sensation.

Different engine configurations are harder than others to balance. Inlines (even numbers of cylinders), horizontals and 90 degree V's are fairly easy. 45 degree V's are a pain in the rear. I'm afraid I don't recall where 60 degree V's fall.

 

I believe 60 degree V's are also naturally easier to balance.

 

have you ever been in a car after the balance shaft is removed? i doubt it. your car feels 20 times more responsive all the way through.