Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Balance shaft?

savage1987

Donating Member
Joined
May 8, 2005
Messages
3,660
Reaction score
31
Points
48
Location
Townsville
Website
www.facebook.com
Members Ride
LS1 VN + WK Grange 0010 + HPW VX SS
fail.

From what I've read last night that is commonly said, but completely wrong. A 90degree V6 is naturally off balance regardless of how well balanced the parts themselves are.

It's not there to balance the bottom end.. it's there to counter harmonic vibrations (the engine's 3rd harmonic or some such). If it were there to replace bottom end balancing, each motor would have to have a differently weighted shaft installed. Doubt very much that Holden went to that much effort lol
 

Thomas1

New Member
Joined
Oct 5, 2006
Messages
599
Reaction score
3
Points
0
Age
36
Location
Melbourne, VIC
Members Ride
VS L67 Statesman
Pffft. Mine isn't hooked up anymore (it's still sitting in there cause I didn't want to have to plug the rear hole, but the gear isn't connected). I haven't noticed any more vibrations at all. But I do have a fairly large cam in there :p. My engine hasn't been balanced either...it's still a stock bottom end.

Ditch it :thumbsup:

I find that the removing balance shaft topic is like a mini spool topic. Those who have never done it/had one tell you it's bad, and those who have tell you to remove it/they are good....
 

leigh 7005

New Member
Joined
Jan 31, 2009
Messages
492
Reaction score
2
Points
0
Location
adelaide
Members Ride
vb sle
ok i just thought it was like the astron engine ones you remove them you gain hp and losse weaight
 

ScoHar

Jizz in my pants
Joined
Apr 10, 2006
Messages
836
Reaction score
7
Points
0
Location
CHCH, NZ
Members Ride
VS Senator
Yea with the Mitsi's you don't have to balance them when removing the balance shaft as engine rotating mass balance is different to what a balance shaft is trying to equalize, balance shafts are really there for driver comfort/smoother engine. I sell Mitsi Balance shaft removal kits i.e frost plug 2 threaded plugs and another size frost plug, and most people I have sold them to have just pulled it out plugged it up. I know its not much use cause were talking about Holden 3800, but they do the same job.

*EDITIf you do balance them without the balance shaft it'll be a bitch to get the right balance ratio but can be done, not by the factory specifications as they will be wrong without the shaft.

and....apparently you gain HP in the 3800 because there is less drag on the timing/drive train sides of things, not sure about mitsi's on that one as most run a separate balance shaft belt.

So in short go for it if you want.
 
Last edited:

Immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
22,472
Reaction score
19,901
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX Calais II L67
holden did alter the weights ofthe ballance shafts between models. the fact that the buick has a rough idle is inpart because the factory ballance is crap. you can achieve a much better ballance and smoother running engine with a proper ballance job, this doesn't alter the fact as has already been stated that with a 90degree V6 things are never going to be as smooth as a inline 6. but don't ever live under the illusion that the factory ballance can't be improved upon.

with regards to removing the ballance shaft on the buick, there is nothing that needs "pluggin up" when it is removed. there is a frost plug behind the rear needle bearing, however you would only remove this if you were changing the needle bearing(if you were intending to keep the ballance shaft). seeing as your just removing the ballance shaft, you can leave the bearing in place and it will be fine.
 
Last edited:

savage1987

Donating Member
Joined
May 8, 2005
Messages
3,660
Reaction score
31
Points
48
Location
Townsville
Website
www.facebook.com
Members Ride
LS1 VN + WK Grange 0010 + HPW VX SS
OK where I stand now is exactly caught between taking it out and leaving it in. I don't think it's a big deal one way or another.

This motor (VR V6 rebuild) is going to cop about 8psi from a turbo soon enough.. does that make my decision any easier?
 

Pub247

Well-Known Member
Joined
Apr 14, 2006
Messages
3,372
Reaction score
59
Points
48
Location
Melbourne S.E.
Members Ride
Ford Fairmont
paradox you can balance a v6 properly as long as theyre a 60 degree one not 90
 

delcowizzid

on holiday
Joined
Jul 8, 2008
Messages
6,988
Reaction score
445
Points
83
Location
NZ
Members Ride
в∞ѕтεכ √&
you can 100% balance the 90 degree v6 as well but they try to lift up off the engine mounts when they are done like that hence why they are not done like this from factory and have the balance shaft to tidy up the resulting vibrations to make the engine smoother.some people get vibration removing the balance shaft some dont each engine is different. vn and vp allso have different weight shafts to suit the different weight cranks as well just on a side note.and yes as said above you can balance the 60 degree v6 as above and they have no balance shaft due to the fact they are 60 degree and are balanced 100%
 
Top