balance shaft

[Tsisaman]

I've looked around and can't really find an answer. What are the pros, cons of removing the balance shaft

 

[92AWDHX40]

Cons none, pros less things to break thats about it youll hear more answers take them out if you can done.

 

[Riceburning101]

Cons: Possibly more vibrations under the hood due to the lack of the balance shafts. It is really hit or miss, unless your building your motor I would highly recommend getting the rotating assembly balanced. Also increased oil pressure can be a problem later.

Pros: Less rotating mass the crank has to turn and less crap to go wrong. Next time, use the search function this has been covered pretty heavily before.

 

[codym]

http://www.dsmtuners.com/forums/cylinder-head-short-block/426621-balance-shaft-removal-no-clue.html

http://www.dsmtuners.com/forums/newbie-thread-graveyard/405976-balance-shaft-eliminator.html

This says 2g, but it's all the same
http://www.dsmtuners.com/forums/newbie-forum/394005-balance-shaft-removal.html


If you decide you want to do it, heres the step-by-step vfaq
Balance Shaft Eliminator Kit Install

 

[erics93talon]

Vibration city! I've had some bolts back loose since the delete.
Just means my hoods open more than normal! Lol

 

[Selling4G63TParts]

I would not recommend removing the balance shaft if you are running a street car. You really don't need to.

 

[BogusSVO]

I would not recommend removing the balance shaft if you are running a street car. You really don't need to.

What is your logic for this?

 

[codym]

I would not recommend removing the balance shaft if you are running a street car. You really don't need to.

Why? If it's done properly, it increases reliability ever so slightly.
The only repercussion of doing this would be increased vibrations, & they honestly aren't that bad. I got used to mine in the 2g in less than a week.

It's not like your going to do a BSE, and then feel like the earth is moving under you everytime you drive.

What is your logic for this?

Ahhh.. Bogus beat me to it by 1 minute!

 

[Riceburning101]

If the rotating assembly is balanced correctly it is hardly noticeable.

 

[Lou98GSX]

street car leave them in . drag car take them out and have the motor balanced .

 

[spyderdrifter]

Only real Con is the oil pressure issue I've read about if the OFH isn't ported. I've had the balance shafts removed on 2 DSMs and the extra vibration was never enough to cause concern. I get more vibration from my poly engine mounts than I did from lack of balance shafts.

 

[Mischif]

The vibrations aren't even really that bad. You only notice it during idle, but once your above 1k you can't even tell.

 

[Diamond Star Werks]

I would not recommend removing the balance shaft if you are running a street car. You really don't need to.

Dude, do you even know what your talking about?

Op only repercussion worth thinking about is oil pump reliability. As when deleting the shafts you leave nothing to support the pump gear in the housing, which had in some cases caused oil pump failures, but alot never have this problem. If this worries you ams sells a shaft without the weight for the oil pump which eliminates this thread completely.
If you don't want to pay for the shaft, then just be sure to keep everything in tune with good oil and change it in time, and maybe use 15w-40. That should eliminate 95% of that threat.

 

[TunaTalon]

If the rotating assembly is balanced correctly it is hardly noticeable.

The balance shafts have no effect on, or relation to, the balance of the rotating assembly.

The balance shafts compensate for differences in velocities of pistons going up from pistons going down. The differences cause a vibration that is two times the period of the crankshaft rotation. If the crank is out of static balance it will cause vibration at the period of rotation. Neither of the two periods can affect the other.

On a high mileage DSM the balance shafts should be either removed or the balance shaft bearings replaced. The balance shaft bearings wear out faster than the main or rod bearings.

When the balance shaft bearings seize the balance shaft belt breaks.
When the balance shaft belt breaks it gets stuck in the timing belt.
With the timing belt jammed, it breaks.
When the timing belt breaks the valves and the pistons “interfere” with each other.
$$$$

 

[Riceburning101]

The balance shafts have no effect on, or relation to, the balance of the rotating assembly.

The balance shafts compensate for differences in velocities of pistons going up from pistons going down. The differences cause a vibration that is two times the period of the crankshaft rotation. If the crank is out of static balance it will cause vibration at the period of rotation. Neither of the two periods can affect the other.

On a high mileage DSM the balance shafts should be either removed or the balance shaft bearings replaced. The balance shaft bearings wear out faster than the main or rod bearings.

When the balance shaft bearings seize the balance shaft belt breaks.
When the balance shaft belt breaks it gets stuck in the timing belt.
With the timing belt jammed, it breaks.
When the timing belt breaks the valves and the pistons “interfere” with each other.
$$$$

Do you really think a rotating assembly that is NOT balanced is going to have a smooth or even close to as smooth of an idle or at any rpm of the engine, opposed to an assembly that has been balanced. Thats like saying a tire/wheel that isn't balanced will have the same ride quality of a balanced one. So yes balancing the assembly will affect how much vibration is caused.

 

[TunaTalon]

Read my post again.
Balancing the rotating assembly will affect the first order vibrations.
The balance shafts affect the second order vibrations.
The second order vibrations are greater than the first order vibrations for any reasonable imbalance.
Being an olde motorhead I both balanced the rotating assembly on my stroker Talon and kept the balance shafts.