evo 4g63 viscous crank damper
 

discuss fluidampr($250.00) vs ati $(470.00) which is better ?

https://img216.imageshack.us/img216/...emediumqv8.jpg

i just ordered mine from jam there runs about 280 a lot less and i bet its better put together

you didn't like the ati ?

The fluidampr unit uses a different concept for dampening than the ATI -- viscous silicone fluid is the dampening material, rather than elastomeric rubber bands. They claim better dampening characteristics than ATI (which might be expected) :) The other main techinical difference is that the ATI has an integral hub, which may have some advantages, but requires a complete timing belt job since installation requires removal of the crank hub. The fluidampr does not. Last, the cost is substantiallly more for the ATI. Different solutions for different engineering preferences...

Just about the most important aspect of an engine DAMPER is the fit to the crank. ATi units require a press fit so it is SUPER TIGHT and transfers all vibration to the damper. A fluid damper just bolts onto the same loose fit crank sprocket that basically falls off once the crank bolt is removed.

There is not a better DAMPER available than Ati, tis why Curt Brown used the ATi.

thats a good point, but if we were to make sure the main crank bolt is tightened. then which is trully better?


Eddie Rosado

The tightness on the circumference of the crank to the damper is what is critical not the tightness of the crank bolt.

In fact the crank bolt itself is not even bolted to the damper unless it is an ATi.

The pulley/damper itself is placed OVER the crank sprocket and bolt and is only held on by small bolts.

The ATi is PRESSED on the crank. BOLTED on by the crank bolt and then the second piece is bolted on by 6 more bolts and torqued to ATi specs.

the only reason curt brown used the ati is because that's all that was available @ the time.

the fluidampr is held on with 4 bolts just like all oe 4g63 crank dampers have been since 1989.

the most important feature is to control torsional vibration. mitsubishi has been using the 4 bolt method of securing it for over 17 years, it is not an issue.

"Each time the air/fuel mixture inside a cylinder is ignited, the combustion that occurs creates a torque spike that is applied to the crankshaft through the piston and rod. This torque spike is so severe that it not only turns the crankshaft, it actually twists the crankshaft ahead of its normal rotation and then the crankshaft rebounds. This twisting action is known as torsional vibration. When these torque spikes and forces get into phase with the natural frequency, critical torsional harmonic vibrations occur and can be seriously destructive to the bearings and the crankshaft. Dampers are designed to control those destructive vibrations.

Critical harmonic vibrations occur numerous times in a engine’s operating range. Stock rubber and elastomer-type dampers are frequency sensitive “tuned absorbers”, and work at only one critical frequency. In the case of a stock rubber damper, it is tuned for a factory engine’s critical harmonic vibrations. If you change the mass of pistons, rods, or the crankshaft, you change the natural frequency of the crankshaft assembly; therefore, the stock damper is no longer tuned to the new frequency of vibration, and you may be headed for early failure of expensive engine components. Dampers also create heat while they work, and rubber is a poor dissipator of heat. This heat and the exposure to the elements deteriorates rubber, causing it to crack and change durometer, which then leads to inertia ring slippage, damper failure, uncontrolled torsional vibration, and costly engine parts breakage." from fluidampr..... to make ttp happy.

Curt Brown is well able to ANSWER FOR HIMSELF.

Curt Brown has not stated this as fact.

In fact if asked, I think he would state quite the opposite.

Cutting and pasting text from Fluidampr's website and pretending you wrote it in your own words is called PLAGIARISM.

Now if you stole that text from a website, you should have also stolen this.
Mitsu has been using 4 bolt stock dampers on STOCK CARS for 16 years.

How does a crank damper help your car???

I used to modify small block chevy engines for roughly 14 years before I got into the imports. I have a great deal of experience in harmonic balancers and I will give my 2 cents.
I have built some pretty nasty small blocks, I have put my hands on everything from 600hp 350's to blown 1200hp stroker 427's. A built V-8 has some wicked torsional vibration that a stock balancer will simply not controll. Out of all the dampers out there, the Fluidamper IMHO, is the best. It controlls all the damaging vibrations in every RPM range and the balancer is one piece. The ATI is a good balancer also but has the rubber damping rings which wear out over time and has to be replaced. That is why the ATI is rebuildable. I have seen 8 and 9 second race only small blocks torn down after a season of racing. Some used ATI, some Fluidamper. From what I saw of the main bearings between the two - I am stuck on Fluidamper. For some reason some of my customers just did'nt want a fluid type balancer on their race engine. I guess they were old school and believed in the traditional rubber balancer. The engines that used the Fluidamper all looked good. The bearings were worn but not down to the copper and I very rarely had to resurface or turn a crank when the Fluidamper was used. Every engine that used the ATI had more wear on the main bearings with some being worn down to the copper, not much more than the Fluidamper but there was a noticeable amount more wear with the ATI. I used the same Chids&Albert bearings on all the engines I built and the same build up process nothing was different except the balancers. These were not street engines, they were 800hp 406 small block chevy's and were used in track only cars. I have many other encounters between Fluidamper and ATI balancers in my years of hot rodding but I could not tell them all here. All I can say is that on every engine I built for myself wether it was mildly modified or a full blown track beast - had a Fluidamper balancer. I tried to get all my customers hooked on Fluidamper but some just would'nt take the advise.
The Fluidamper is sealed, one piece, and has no parts that wear out over time. The Fluidamper is also impervious to heat unlike the ATI. I'm not bashing ATI because it still is a damn good balancer but for the average street/occassional track guy and even the full tilt drag racer, the Fluidamper is just an easier balancer. All you really have to do with the Fluidamper is bolt it on and go. The ATI will require frequent inspections and a teardown and rebuild when the rubber rings go out. As far as I'm concerned the Fluidamper does an outstanding job of eliminating damaging torsional vibrations and extending the life of the crank and main bearings all while requiring zero maintenance.

ATi dampeners are approved for 10years between inspections. Will you own your Evo in 2016?

Many have expressed that the fluid dampers may run out of balance until heated up to normal temperature and the fluid becomes more viscous.

I don't have an aftermarket balancer on my EVO for one and after building small block Chevy's for 14 years I can tell you that a Fluidamper does not "run out" of balance as heat rises. The local team that I built the stroker 406 small blocks for, my own personal stroker 421, and the numerous other engines that I have torn down and rebuilt after going through either many miles or a grueling drag race season all have shown absolutly no significant signs of premature wear and the main bearings and cranks have looked outstanding saying what some of these engines have gone through. The few engines that I used the ATI on were still in good shape but had more wear than the engines that used the Fluidamper. I'm only talking on my own personal experience and what I have seen first hand in my 14 years building some wicked mouse motors.

BTW, I have never actually seen or heard of any of my fellow engine builders or race teams that I associated with back in the day that used the ATI go 10 years without having to replace the rings. As a matter of fact one race team that ran a 415 mouse had an ATI fly apart at the end of their 8.17 pass, it pretty much destroyed the engine. Their 10,000 dollar engine was reduced to a worthless pile of junk in a matter of seconds. They failed to rebuild the balancer because they did'nt think it needed to be - the balancer was about 2 years old.

This is great info to know.

You read that opposite. Their concern was at COLDER temperatures the fluid would favor one side and actually run out of balance until heated up.

The ATi Evo dampers are rated to 800HP. I am not sure what brand the 7 or 8 second car was running, but I assume it had over 1000bhp.