What is this for???


sorry so small

That's so small I can't tell. Was it a cell phone pic or something? Is it in the LIM?

I'm guessing youre talking about the balance shaft?

It does what it sounds like it would. Balances the engines rotating mass more giving it less vibration. In a nutshell of course.

Tony's right if that's what you are pointing at. It's a vibration reducer.

In the 3800 engine the balance shaft is an absloute necessity. Without it not only does it lope like a limping donkey but the engine shakes itself apart in relatviely short order.

If you search the web you should find a nice article about the balance shaft, why it's in there (it was not in the early 3800s) and how it makes the engine purr so nice at idle you can set a (pretty) full glass of water on the top w/o incident. To learn more specifically about the 3800 engine's inherent first-order imbalance, see:

http://engine.firebirdv6.com/3800history.html

and for more about engine balance shafts in general see:

http://en.wikipedia.org/wiki/Balance_shaft

Happy reasing,

Albertj

Actually, it's not completely necessary - If you 'upgrade' to a double-roller timing chain, you have to leave the balance shaft disconnected. I would never do this on a street car, I have driven a few and the vibration, although not horrible, is... pretty bad.

yea thats what I thought it was, again sorry about the size and thanks for the info

Completely necessary = no. Derek you're right - the engine willrun for some number of hours without one.

Desirable and useful = yes, even though it drags off some horsepower.

Albertj

By disabling the Balance Shaft, do you have to remove it completely?
If so, what does it involve. Are there plugs or something that go in it's place or is nothing necesary other than just removing it.
I understand if I want to change my Timing Chain to a heavier duty one, I have to remove the balance shaft and was wondering what's involved.

rick, do a search on "disabling the balance shaft on a 3800 motor" and you will find lots of interesting info on how to. it sounds like a good mod with little consequence just a little more vibration. i like the idea but is a pia to do....

Thanks for the info.
I'll do some research and see if I want to do it along with doing the LIM gaskets and new L32 Lim and Gen 5 SC next spring.
Because I've already installed the 105# valve springs I'll be able to get a look at the timing chain and tensioner and see how much wear the springs caused if any. I'm curios after reading so many warnings about doing what I did.
I'll probably have about 5 - 6,000 miles, maybe more, on it with the new springs before i get to pull the timing cover. Will be a good experiment.
If there is heavy wear then I'd like to go with the double roller chain and new tensioner. Which will necessitate the removal of the balance shaft.
Then if your going that far in might as well do a mild cam also.
Ah, what the hell. This increase in Torque is addictive.

does anybody here have the BS removed? and what do ya think?