Balance shaft removal

niss720 · Post by **niss720** » Tue Oct 30, 2012 11:11 am

Does anyone know where I can get a balance shaft removal kit from for wideblock in Australia? Are they different to the twin cam ones? Does it come with what you need to block the oil holes ect?

Thabks

ProZac · Post by **ProZac** » Tue Oct 30, 2012 1:53 pm

I don't know where you could source a kit... But it's pretty easy to do without a kit. If you do a few searches I'm sure the process is pretty well documented on here.

Basically you cut the lower shaft off and just use the snout of it in the oil-pump, and seal the other end with a grub screw. Insert the upper front bearing rotated so it blocks the oil supply hole, and use a 35mm frost plug to seal the hole in the front timing cover. You also have to use a shorted bolt where the balance shaft belt tensions used to attach.

From memory you don't have to do anything about the rear bearings, as they are supplied oil via the hollow center of the shafts themselves, and don't source any from the block directly... But I'm slightly unclear on this and it would be worth confirming.

ProZac · Post by **ProZac** » Tue Oct 30, 2012 2:03 pm

There are also a couple of schools of thought as to whether you should remove the lower shaft, or just machine the lobes off. The issue is that the length of the shaft, and the presence of a rear bearing provide added support to the oil-pump. I've always just chopped it off, but I think I'll machine the lobes off next time I do one, purely for peace of mind.

FST4RD · Post by **FST4RD** » Tue Oct 30, 2012 2:05 pm

Does removing the balance shafts give you any more performance? I could imagine 5 pooftenths of a hp?
Talking to an experienced mitsi mechanic, he said the problem with the balance shafts is that when people replace the cam belt they don't replace the little belt driving the other balance shaft, then it breaks because it's done far to many ks and goes through everything.

ProZac · Post by **ProZac** » Tue Oct 30, 2012 2:08 pm

Bingo, that is exactly what happens. The number of people I've had tell me not to worry about the balance shaft bits when I sell them timing bits for a mitsy... Usually I try pretty hard to talk them into it, as it's critical.

The motor in my car has obviously had it break previously, as the alloy casing is smashed out right in that area. Still works fine, but looks pretty ugly, I think I'll replace it while i have it off the road.

FST4RD · Post by **FST4RD** » Tue Oct 30, 2012 2:24 pm

I also understand that unless you have a lot of hp, like a lot, it's a pointless mod? All it's going to do is make the car shake and vibrate more?

Post by **Alspos** » Tue Oct 30, 2012 3:35 pm

The shafts are used to balance the harmonics created by a 4 cylinder engine. By rights, it makes the engine run smoother......it does not have anything to do with the rotating assembly balance.

Post by **Alspos** » Tue Oct 30, 2012 3:51 pm

I just looked it up......HERE

redzone · Post by **redzone** » Tue Oct 30, 2012 8:24 pm

The only time I would pull them is if you were building an engine that would see over 8k regularly, due to the high rpm they see.

Steve's widey still has them in and is nice to drive as a result, removing them does not give you any extra hp, all it does is increase vibration & give you a slight decrease in rotating mass similar in effect to a lightened flywheel.

niss720 · Post by **niss720** » Tue Oct 30, 2012 9:58 pm

Thanks for your replys, I did not want to remove them at first but guy at the machine shop talked me out of it as the bearing holder was damaged when the bearing fell out (some how)

4g64 starion · Post by **4g64 starion** » Thu Nov 01, 2012 3:46 am

I have removed them in my 4g64 and the only differece was a small vibration at 2800rmp.

Austarion

Balance shaft removal

Balance shaft removal

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