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Damn. So Hank says there is too much nvh.
Would there be any way to reduce nvh without compromising performance?
Camber plates?
No...... There's a reason they spent time engineering this and money installing it..... If you have a track dedicated car you are trying to get max performance out of without caring about drive-ability, this mod is for you. If it's anything else, I seriously doubt this is a change you want on your RS......
 

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I think Hank did upgrade all his motor mounts though.

From what I read if its just the RMM upgrade, the NVH should not be too bad.
 

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It's not the first car that I've removed the balance shaft.
But time will tell.
More research is needed!
Let us know, but I imagine reinstalling the balance shaft would be quite a hassle to make sure it's lined up correctly. I'd much rather spend the afternoon installing some bolt-ons onto my daily vs taking off the balance shaft
 

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Thought I'd add to this thread since I just did this mod to my car. I have the Mountune B2 package on my car and this. I feel a bit more vibration on a cold start when it's idling at 1200rpm. Once warmed up and idle drops I can't tell if it's vibrating more or not... Maybe? Lol.
Definitely feel no vibrations while driving. Engine spins up faster and that feels nice. Only issue is when I put the oil pan back on and was waiting for the gasket maker to set up, I found the rubber o-ring for the oil pick up tube on my floor ?. That sucked huge... So did the job twice. Car has 1300km on it. I don't bother to wait to mod anymore cause I know from experience, I'll never come close to leaving it stock for the warranty period. Lol.
 

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Thought I'd add to this thread since I just did this mod to my car. I have the Mountune B2 package on my car and this. I feel a bit more vibration on a cold start when it's idling at 1200rpm. Once warmed up and idle drops I can't tell if it's vibrating more or not... Maybe? Lol.
Definitely feel no vibrations while driving. Engine spins up faster and that feels nice. Only issue is when I put the oil pan back on and was waiting for the gasket maker to set up, I found the rubber o-ring for the oil pick up tube on my floor ��. That sucked huge... So did the job twice. Car has 1300km on it. I don't bother to wait to mod anymore cause I know from experience, I'll never come close to leaving it stock for the warranty period. Lol.
Sweet, good to know. Time to enjoy the car!
 

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Damn. So Hank says there is too much nvh.
Would there be any way to reduce nvh without compromising performance?
Camber plates?
The only way to minimize the secondary imbalance (and therefore vibrations) caused by removing the balance shaft assembly is to lighten up the rods and piston assemblies. The secondary vibes that the balance shafts counteract are a consequence of the engine and crank format (inline 4 with flat crank) Lightening the reciprocating components will reduce but not eliminate the the secondary imbalance.

Ciao
 

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The only way to minimize the secondary imbalance (and therefore vibrations) caused by removing the balance shaft assembly is to lighten up the rods and piston assemblies. The secondary vibes that the balance shafts counteract are a consequence of the engine and crank format (inline 4 with flat crank) Lightening the reciprocating components will reduce but not eliminate the the secondary imbalance.

Ciao
So would taking out the balance shaft wear our the crank faster? As it would have less balanced forces on it?

What if you balanced the whole rotating assembly including the flywheel?
 

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The UK Mountune demonstrator car has been running for some 18 months without hiccup with its Balance Shaft Assembly removed and that’s also over 400hp and as a demo car it surely won’t have an easy life.

Even the YouTube guy Sheemee150 drove the Mountune demo car and never mentioned any additional vibrations.

I’ve also done mine and it revs like (in principle it’s the same) as if you’ve lighted the flywheel and you drive according to the lesser rotating mass. It’s like traditional tuning lightening and balancing the crank assembly.

But it sure does rev up a lot quicker, it’s like a fireblade now on the revs.

You may stall it for maybe once or twice then you adjust the feel and revs to compensate for the lesser rotating mass and it’s kinetic energy flipping the flywheel around.
 

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So would taking out the balance shaft wear our the crank faster? As it would have less balanced forces on it?

What if you balanced the whole rotating assembly including the flywheel?
The balance shaft is NOT actually balancing the crankshaft. It is just canceling the harmonics produced by the crank/rods/pistons, that the crank counterweights are unable to remove. The flywheel on this engine is "zero" balanced, so it has no effect on engine balance whatsoever.

With that said, no way I'd remove it on a street car. While the balance shaft may be ~10 pounds of rotating mass, it is very small in diameter, so it doesn't have nearly the effect of removing 10 pounds from the flywheel or clutch. Another way to put it is 10 pounds on the flywheel carries much more inertia than 10 pounds on the balance shaft. If you want faster engine response, lighten the flywheel and leave the balance shaft intact.

Anyone who doesn't understand this should look up the YouTube guy "EngineeringExplained" and watch his videos about primary and secondary engine balancing. He does a pretty good job of explaining it.
 

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So would taking out the balance shaft wear our the crank faster? As it would have less balanced forces on it?

What if you balanced the whole rotating assembly including the flywheel?
No not appreciably, the vibrations are a little harder on the components including the bearings but it probably a bigger issue for the ancillary items attached to the engine more than the internals. Eventually over the long term it will have its effects though.
You cant eliminate these particular vibrations by balancing the rotating assembly. The vibrations in this case are caused buy the fact that as the piston moves through its stroke it moves lineally further in the first 90 deg of rotation than the subsequent crank angles of rotation due to rod angularity and length. With a flat crank 4 cylinder engine you can't balance out these forces naturally, you need balance shafts. An inline 6 does as a consequence of its design. You can obviously make the engine as smooth as is possible for the given design but there's a reason Ford put the balance shafts in there and you pay the price for removing them. Some think thats a price they're willing to pay for the added performance and simplification.

Ciao
 

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If it’s a fundamental problem of the four pot engine and a Balance Shaft is required.
How did all the Crossflow Pinto CVH engines and every other Ford Four pot pre-Ecoboost survive with all the vibrations and harmonics and No balance shaft and the engineering then isn’t as good as the engineering now.
 

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If it’s a fundamental problem of the four pot engine and a Balance Shaft is required.
How did all the Crossflow Pinto CVH engines and every other Ford Four pot pre-Ecoboost survive with all the vibrations and harmonics and No balance shaft and the engineering then isn’t as good as the engineering now.
Its about thresholds. Capacity,specific output,rpm,component life and customer expectations. Eventually you reach the threshold where the vibrations are a factor that the manufacturer considers warrants addressing.
Plenty of people have done the delete and dont think the vibes are an issue but remember this engine family is used in many applications most of which are not performance orientated so it needs to feel a little refined for the more conservative owners.

Ciao
 

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拆下平衡軸機油容量提升約1.2升,平衡軸重量實際只有5.19公斤
Translated:
The oil capacity of the balance shaft is increased by about 1.2 liters after the balance shaft is removed, and the weight of the balance shaft is actually only 5.19 kg
 

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Translated:
The oil capacity of the balance shaft is increased by about 1.2 liters after the balance shaft is removed, and the weight of the balance shaft is actually only 5.19 kg
The oil volume is correct, but the BS assembly weight is light by a good bit. The steel bolts and shims must be added into the mix for a total weight drop...
 

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Another reason to delete your balance shaft is, its only been balanced to 6000rpm. After this it incurs a slight vibration and has lead to numerous assemblies coming adrift and hitting the rotating mass of rods and crank meaning another kaput engine.
If your revving your engine high its best to delete this as its a time bomb and removing it wont really matter in my experience.
 

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Another reason to delete your balance shaft is, its only been balanced to 6000rpm. After this it incurs a slight vibration and has lead to numerous assemblies coming adrift and hitting the rotating mass of rods and crank meaning another kaput engine.
If your revving your engine high its best to delete this as its a time bomb and removing it wont really matter in my experience.
Interesting, is there a source of that information?
 
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