Fluidampr vs ATI

Belgian1979vette

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Okay, this is a discussion going on, but i'm looking for people that had actual problems with a Fluidampr.

The story goes that Fluidampr's break off the nose of a crank and many racers seem to be advise against them in favor of the ATI's (elastomer).

However, I haven't found any real proof of a broken off nose, so this kinda seems like the story of HV pumps sucking oil pans dry.

Anyone here have any real life data on this ?

I currently have a Fluidampr that I choose because the components in my engine differ substantially from stock and I wanted to make sure the balancing range was wide enough. If however the fluidampr is actually a problem i have no problem switching, unless this is one of those tales spread on the inet.
 
Okay, this is a discussion going on, but i'm looking for people that had actual problems with a Fluidampr.

The story goes that Fluidampr's break off the nose of a crank and many racers seem to be advise against them in favor of the ATI's (elastomer).

However, I haven't found any real proof of a broken off nose, so this kinda seems like the story of HV pumps sucking oil pans dry.

Anyone here have any real life data on this ?

I currently have a Fluidampr that I choose because the components in my engine differ substantially from stock and I wanted to make sure the balancing range was wide enough. If however the fluidampr is actually a problem i have no problem switching, unless this is one of those tales spread on the inet.

Believe me when fluid dampners came out it was a common problem mostly in circle track applications and most teams went to the BBC snout which cured the problem. But even now its very common to see ATI's on every engine!!!

The other problem I see with fluid balancers is you can not balance a crankshaft with one the crank!!!! As it will not repeat and that a good enough reason for me not use one.
 
Okay, this is a discussion going on, but i'm looking for people that had actual problems with a Fluidampr.

The story goes that Fluidampr's break off the nose of a crank and many racers seem to be advise against them in favor of the ATI's (elastomer).

However, I haven't found any real proof of a broken off nose, so this kinda seems like the story of HV pumps sucking oil pans dry.

Anyone here have any real life data on this ?

I currently have a Fluidampr that I choose because the components in my engine differ substantially from stock and I wanted to make sure the balancing range was wide enough. If however the fluidampr is actually a problem i have no problem switching, unless this is one of those tales spread on the inet.

Believe me when fluid dampners came out it was a common problem mostly in circle track applications and most teams went to the BBC snout which cured the problem. But even now its very common to see ATI's on every engine!!!

The other problem I see with fluid balancers is you can not balance a crankshaft with one the crank!!!! As it will not repeat and that a good enough reason for me not use one.

The last I can understand, but what about a internally balance crank ? Same with those ?
 
Okay, this is a discussion going on, but i'm looking for people that had actual problems with a Fluidampr.

The story goes that Fluidampr's break off the nose of a crank and many racers seem to be advise against them in favor of the ATI's (elastomer).

However, I haven't found any real proof of a broken off nose, so this kinda seems like the story of HV pumps sucking oil pans dry.

Anyone here have any real life data on this ?

I currently have a Fluidampr that I choose because the components in my engine differ substantially from stock and I wanted to make sure the balancing range was wide enough. If however the fluidampr is actually a problem i have no problem switching, unless this is one of those tales spread on the inet.

Believe me when fluid dampners came out it was a common problem mostly in circle track applications and most teams went to the BBC snout which cured the problem. But even now its very common to see ATI's on every engine!!!

The other problem I see with fluid balancers is you can not balance a crankshaft with one the crank!!!! As it will not repeat and that a good enough reason for me not use one.

The last I can understand, but what about a internally balance crank ? Same with those ?


Yep same with this those balancers and thats what I was talking about any ways.
 
Okay, this is a discussion going on, but i'm looking for people that had actual problems with a Fluidampr.

The story goes that Fluidampr's break off the nose of a crank and many racers seem to be advise against them in favor of the ATI's (elastomer).

However, I haven't found any real proof of a broken off nose, so this kinda seems like the story of HV pumps sucking oil pans dry.

Anyone here have any real life data on this ?

I currently have a Fluidampr that I choose because the components in my engine differ substantially from stock and I wanted to make sure the balancing range was wide enough. If however the fluidampr is actually a problem i have no problem switching, unless this is one of those tales spread on the inet.

Believe me when fluid dampners came out it was a common problem mostly in circle track applications and most teams went to the BBC snout which cured the problem. But even now its very common to see ATI's on every engine!!!

The other problem I see with fluid balancers is you can not balance a crankshaft with one the crank!!!! As it will not repeat and that a good enough reason for me not use one.

The last I can understand, but what about a internally balance crank ? Same with those ?


Yep same with this those balancers and thats what I was talking about any ways.

Hm, correct me if I'm wrong but an internally balanced crank is supposed to be balanced without the flywheel and damper. Those intended for use with an internal balanced crank are normally 0 balanced by themselves...
 
An internally balanced crank has counterweights large enough to be balanced without an additional counterweight on the damper or flywheel/flex plate. This has nothing to do with bob weight balancing the crank and getting it spot on by adding mallory metal and/or drilling the damper for a neutral balance.

The roller blocks are also called internal balanced, they are only about 3/4th internally balanced since the roud rear crank face has no balance pad like the earlier ones. It's just nomenclature, nothing more. The externally balanced cranks would need counterweights that are too large to fit the crank case to balance without resorting to heavy (mallory) metal, hence called ext. balanced.

Even the internal balance crank is balanced with the whole assembly in place and bob weights mimicing the pistons, rings, rods, pins.

Pic of crank with damper & flexplate and bob weights on the journals

tt-bal.jpg

As for repeatability, what he means is that if you spin balance the assembly with a fluidampr and then drill it to compensate and spin again that the imbalance will not repeat in the same location it will have shifted.

A buddy of mine has a fluidampr on his 428CJ engine and it has a fluidampr that some German shop tried to balance too. They drilled a snot load of dimples on it (drill too deep and it's ruined because you go right through). I don't know if they just said "F it" after a while but the damper will come off.
 
Fluidampr says that you should separate the inner hub from the outer body of the damper for balancing.
You just spin the inner hub, and then reassemble when you are done. It doesnt seem like it would be too difficult to do that.
 
ATIs can be disassembled, the hub and ineria ring are bolted together on the super dampers. Don't think so on the street dampers but not 100% sure. Some even come unassembled and you have to put them together yourself (like the LT1 one because you can not install it assembled on the car)
 
Fluidampr says that you should separate the inner hub from the outer body of the damper for balancing.
You just spin the inner hub, and then reassemble when you are done. It doesnt seem like it would be too difficult to do that.

You cannot disassemble them.

According to Fluidampr, you can disassemble the external balanced units.
For internal balanced dampers, there is no reason to spin them. They are zero balanced from the manufacturer.
 
read above, zero balance has to do with engine design, either needing or not needing 1 or 2 external weights (roller SBC only on rear, 400 etc front and rear) it has NOTHING to do with spin balancing a rotating assy.
 
I've always wondered how useful custom balancing is. Unless you get the piston and rod weight perfect i don't know what the point is. And that doesn't account for all the piston friction.

It makes a crapload of money for machine shops though. I'm considering not having the rotating assy for my next motor balanced. Actually i've never done that and i don't know anyone who has.

What's the chance that your replacement pistons on a rebuild are the exact same weight as the originals. People just press the new ones on and go.
 
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Fluidampr says that you should separate the inner hub from the outer body of the damper for balancing.
You just spin the inner hub, and then reassemble when you are done. It doesnt seem like it would be too difficult to do that.

You cannot disassemble them.

According to Fluidampr, you can disassemble the external balanced units.
For internal balanced dampers, there is no reason to spin them. They are zero balanced from the manufacturer.

I have spun up a fluid balancers before and they donot repeat so how can they say they arre zero balanced.
 
I've always wondered how useful custom balancing is. Unless you get the piston and rod weight perfect i don't know what the point is. And that doesn't account for all the piston friction.

It makes a crapload of money for machine shops though. I'm considering not having the rotating assy for my next motor balanced. Actually i've never done that and i don't know anyone who has.

What's the chance that your replacement pistons on a rebuild are the exact same weight as the originals. People just press the new ones on and go.

So 175 dollars is a crap load of money to balance a crank HMMMMM, The new Sealed power pistons are on average 70 grams liter then OEM pistons and I balance for a lot of machine shops that don't balance and these lighter pistons are cauesing some vibration issues and causing the shops to pull the enignes down and balance the rotators.

Its always best to weigh all the old parts against the now ones and they make a decision.

A balanced engine is a much happier one then one that is not.
 
Fluidampr says that you should separate the inner hub from the outer body of the damper for balancing.
You just spin the inner hub, and then reassemble when you are done. It doesnt seem like it would be too difficult to do that.

You cannot disassemble them.

According to Fluidampr, you can disassemble the external balanced units.
For internal balanced dampers, there is no reason to spin them. They are zero balanced from the manufacturer.

I have spun up a fluid balancers before and they donot repeat so how can they say they arre zero balanced.

Carl,

I think you're right. If the thing cannot be balanced, how did they do it in the factory. You could of course balance the hub and the inertie ring seperate, but then it would have an imbalance again when the silicone gets added.

This could account for the reason why with higher rpms people are reporting breaking cranks.

I ordered an ATI to replace it.
 
Fluidampr says that you should separate the inner hub from the outer body of the damper for balancing.
You just spin the inner hub, and then reassemble when you are done. It doesnt seem like it would be too difficult to do that.

You cannot disassemble them.

According to Fluidampr, you can disassemble the external balanced units.
For internal balanced dampers, there is no reason to spin them. They are zero balanced from the manufacturer.

I have spun up a fluid balancers before and they donot repeat so how can they say they arre zero balanced.

Carl,

I think you're right. If the thing cannot be balanced, how did they do it in the factory. You could of course balance the hub and the inertie ring seperate, but then it would have an imbalance again when the silicone gets added.

This could account for the reason why with higher rpms people are reporting breaking cranks.

I ordered an ATI to replace it.


Smart move !!!!
 
read above, zero balance has to do with engine design, either needing or not needing 1 or 2 external weights (roller SBC only on rear, 400 etc front and rear) it has NOTHING to do with spin balancing a rotating assy.

I understand that. When I said zero balance, what I mean was that being a balancer for an internal balanced assembly, that there was no imbalance.
Therefore spinning it on the balancing machine does not affect the balance of the assembly.
 
Streetdamper from ati is fine just not sfi. It's an excellent damper

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