balance shaft removal??

[tuckin20s96]

i was wondering if removing the balance shaft out of the 4.3's would add anymore hp. i used to be into dsm's and a big thing when building a motor for them was to remove the balance shafts. anyone know if this can be done or is worth while doin while i have my motor apart?

[brokeitagain]

it makes them a little rough, u will have to leave it in there for oil pressure. But just removing the gear from it will be fine,The gains may be small but any reduction in parasitic drag will help. U should remember that DSM's shaft may be geared to turn double crankshaft speed. These 4.3's are geared to run at crank shaft speed. I took the gear off mine because i still had a balance shaft rattle after i replaced the timing set and added GM's chain damper. Mine does have a bit of a rough idle but it doesnt bother me. As long as my motor mounts stay good i barely feel it

[tuckin20s96]

yeh dsm's do turn at twice the speed of the crank. thats something i didnt think about. it was just a thought anyways, i figured id ask an see if anyone had done it. thanks

[MINTSICK]

Not worth it on a 4.3, I considered leaving mine out when I rebuilt but decided against it for the minimal gains on a daily driven vehicle...Maybe if it was a dedicated track vehicle where every bit of HP mattered.

[Crew Cab Sonoma]

Quote: Originally Posted by brokeitagain

it makes them a little rough, u will have to leave it in there for oil pressure. But just removing the gear from it will be fine,The gains may be small but any reduction in parasitic drag will help. U should remember that DSM's shaft may be geared to turn double crankshaft speed. These 4.3's are geared to run at crank shaft speed. I took the gear off mine because i still had a balance shaft rattle after i replaced the timing set and added GM's chain damper. Mine does have a bit of a rough idle but it doesnt bother me. As long as my motor mounts stay good i barely feel it

i presume disabling the shaft got rid of of that annoying rattling noise?

[Atrus]

I'm with Mint on this one. I completely removed and eliminated the balance shaft in my stroker 4.3 and would never do it again. I don't care about the idle so much, it's got a comp 280 after all...but doing it right was a pain. Instead of ditching the large gear, I had the machine shop cut and lathe it down so it functioned as a spacer between the cam and timing set, so I could run the standard timing setup. That took forever, it's a lot of metal. I addition, to my knowledge, doesn't the balance shaft provide oil for the timing set and doesn't it throw some oil onto the cam, lifter valley etc.? We had to put a fitting into both sides of the block where the balance shaft it to tap into the oil supply. After that we made a long spray bar that oiled the cam and lifter valley. This may have been overkill after the fact. We then had to plug both of the holes for the balance shaft. One's easy, it's a freeze plug, and I can't remember what I ended up doing for the part that's under the front cover.

It seems to be functional as of now. But as far as the hassle, nope, I'd probably sacrifice the 1-2hp it takes, if that. Guess my setup doesn't make any noise though...

[brokeitagain]

The rattle was the reason for my elimination of the balance shaft.No more rattles

[Crew Cab Sonoma]

Quote: Originally Posted by brokeitagain

The rattle was the reason for my elimination of the balance shaft.No more rattles

thanks. i`m tempted to disable it just for the noise it makes...
tired of people asking whats wrong with my engine...

[Crew Cab Sonoma]

Quote: Originally Posted by Atrus

I'm with Mint on this one. I completely removed and eliminated the balance shaft in my stroker 4.3 and would never do it again. I don't care about the idle so much, it's got a comp 280 after all...but doing it right was a pain. Instead of ditching the large gear, I had the machine shop cut and lathe it down so it functioned as a spacer between the cam and timing set, so I could run the standard timing setup. That took forever, it's a lot of metal. I addition, to my knowledge, doesn't the balance shaft provide oil for the timing set and doesn't it throw some oil onto the cam, lifter valley etc.? We had to put a fitting into both sides of the block where the balance shaft it to tap into the oil supply. After that we made a long spray bar that oiled the cam and lifter valley. This may have been overkill after the fact. We then had to plug both of the holes for the balance shaft. One's easy, it's a freeze plug, and I can't remember what I ended up doing for the part that's under the front cover.

It seems to be functional as of now. But as far as the hassle, nope, I'd probably sacrifice the 1-2hp it takes, if that. Guess my setup doesn't make any noise though...

you are right about there not being any significant power gains from disabling it.
but it sounds like you went through too much trouble. the spray bar arrangement wasnt necessary...
just plug to oil feed holes off.
i would want to remove the entire asy. myself, just because i hate leaving dead weight hanging around.
and i would also cut down the drive gear behind the cam sprocket as well, but i would just use my trusty angle grinder to take care of that...