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I've heard of people removing the balance shaft assembly from the engine but nobody says anything about vibrations or how the engine runs after that, does it cause any noticeable vibration in the engine??
 

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85 New Yorker 2.2 T1, 89 LeBaron Convertible 2.5 T1
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It's noticeable if you're looking for it. My Daytona had the chain cut but the balance shafts were left on. I honestly never noticed any difference in power between a motor with or without them, and I don't know if anyone has actually scientifically tested the difference it makes.

Personally, I'd only do it if I had some other reason to go down there. Oil pan gaskets can be a PITA. The 2.5 8v I just installed in my Spirit still has the balance shaft hooked up, and it has new motor mounts. You don't feel the engine at all at idle.
 

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I've seen Engines with burned rod bearings due to faulty balance shafts.

They connect directly to the Engine oil gallery so if they're loose inside...

I remove them from all my Engines and never noticed any difference.

The Engine runs just as smoothly after removal as it did before.

The smoothness is just my opinion, I had no way to quantify it.

They may rob a bit of power but that's of no concern to me.

It's the possible internal oil leak that I want to eliminate.

Thanks
Randy
 
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sitting in the passenger seat of my mother's then new '91 shadow..2.5 auto,it had a little growl as it drove away from a stop ..it came from down below/behind the heater box..

and it was the technology shared with porsche as advertising ,in the day claimed..

in a north south layout with more solid mounting than our bobbling engine mounts ..like the 944 porsche the balance shafts came from.. others, not us might notice more effect than a little growl..
 

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I removed the balance shafts and plugged the oil supply to them in the 2.5 (injected, NA) that I put in my '86 GLH look-alike. It has much more power than the stock TBI 2.2 in my '88 Omni, but there is very noticeable vibration at idle, especially when the A/C is on. I'm not sure if the performance difference off the line is due to the bigger engine or the deleted balance shafts, or a combination of both, but I DO like the increase in power. If I give it an additional 1 or 2 hundred RPM at idle, the vibration goes away. WHen the engine is cold and still idling slightly higher, there is no vibration, or very little.
 

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Balance shafts are for secondary vibrations. If you open the hood and where able to turn them on and off you could see it. It's a very slow oscillating movement. You'd never feel it in the car. Ditch them.
 

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My '91 Dakota has the nat. asp. 2.5 and it uses a special oil pan that is only used in the truck. No room for balance shafts, but it runs quite well without them. If you remove the balance shafts, it saves weight, but you have to plug the oil hole. One solution is a to make a metal tab held over the hole by an adjacent bolt. The oil pan seals easily with RTV silicone..
 

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Straight from www.thedodgegarage.com
If you haven't been there before or don't know about it, this site has more info about FWD Mopar than you can imagine!

Balance Shafts
2.5 SOHC and 2.2 16V owners can remove the balance shafts in the oil pan and pickup 10-14 hp for free- they are for secondary order vibrations and are not needed for normal operation. I have done several turbo and non-turbo cars with no ill effects. Some people have voiced concerns over this mod saying the shafts are need to control vibration, to which I respond that's nonsense! Did you know 88-95 2.5 Dakotas don't come with them? There is no room for them in the truck oil pan!

Just drop the oil pan, remove the 6 bolts holding the balance shafts in, cut the chain attached to the front of the crankshaft and remove it. Plug the oil feed hole, which is located next to the number 1 main cap, with a pipe plug (you will have to tap out the hole), reinstall the oil pan and your done.

Another bonus is less engine noise and a pan that holds another quart of oil.


WARNING!!!!
YOU MUST PLUG OFF THE OIL FEED HOLE TO THE BALANCE SHAFTS
OR LOSS OF OIL PRESSURE AND ENGINE DAMAGE WILL OCCUR!!!!


True story about balance shafts! Just learned this one from a retired Chrysler engineer- Seems the only reason the 1990-1993 2.2 Turbo III & VNT motors had balance shafts was that the guys on the assembly lines were forgetting to install balance shafts on the 1989 2.5 motors after a holiday!! It's true! The block would come down the line after a holiday or weekend and the assembly line guys would forget to install the shafts in the first couple of engines causing massive oil pressure loss.

The fix? Install balance shafts in ALL the TURBO ENGINES as of the 1990 model year.
 
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