i do not have removed the balance shaft in my 92 bonneville sse supercharged car and i do not notice any extra vibration and i have over 5000 miles on the rebuild. i have found no problem in removing it at all....

yeah lol my bad.....i did have the balance shaft removed during my rebuild and it didn't affect anything that i can tell

It may over time.

If it was removed, how were the holes in the block sealed?

After thinking about it, removing the shaft and having no ill effects would require LOTS of machine time. Balancing the pistons and crankshaft actually would probably eliminate the need for a balance shaft...my thinking is that GM decided to go with a balance shaft because it is cheaper to go that route instead of having to balance every single rotating component that goes into every engine. Even the Chrysler 2.5 Turbo guys that know what'* what would ensure the internals are balanced before taking the balance shafts out.

As said before, removing the balance shaft and ONLY doing that and nothing else, yeah the engine will probably silently shake itself to death. But I think with proper component balancing it could work, provided you aren't afraid to drop the coin for that sorta thing.

This is not true. The balance shaft is there to cancel out vibrations due to combustion. Balancing the engine will help it run smoother but it has nothing to do with the harmonics the balance shaft cancels out.

^^^ This is correct. Vibration caused by the rotating assembly (crank, rods and pistons) moving up and down is called first degree vibration and is taken care of (mostly) when the rotating assembly is balanced at the factory. The balance shaft is there to control second and third degree vibrations, such as the V6 "rocking couple" vibration, which can let the engine shake itself appart.

I wouldn't remove the balance shaft on any daily driver. Sure some of the race guys on 3800Pro and elsewhere have done it, but they're pushing those engines so hard they have to rebuild them at least once a year anyway. They aren't going to have time to witness the long term effects of removing the balance shaft when they're pushing an engine so hard that it only lasts a few runs down the track.

It'* important to remember that virtually every performance mod hurts long-term reliability. GM could easily sell a 300+ HP NA 3800 that still passed emissions, but it wouldn't last longer than 50,000 miles. And; this can be said about almost every part on the car; GM wouldn't put the balance shaft there if it wasn't needed. Remember, every part they put in that engine costs them money.

I have a 1998 L67 and I removed my balance shaft so I could install a stronger double roller timing chain. The engine has a very slight feeling of worble during idle only but so does my Vette with the stock cam. so... so what. So it has the big cam feel. how bad could that be.. :P If I had a worble at idle because it was a fat cam, I'd be cool right? Maybe without the balance shaft you can simply feel the cam like you would in a V8? yep.. see my point.
I'm not worried that its going to increase over time, that'* just silly.
Techniccally the engine should be able to spin up faster but I don't really think anyone could tell.
I say go for it if you are planning on upgrading your timing chain.
If you like, I'll throw my balance shaft on the scales tomorrow morning and I'll post the actual weight for you.
I say go for it.

There isn't a double-roller timing chain for the S1. Only a stronger OEM style chain that doesn't require a BS delete.

Ahh.. gotch-ya.

Ok, so i was addressing the subject with my general opinion when it applies. :P