damper thoughts running a gear drive

what are your thoughts on choosing a damper when running a gear drive ?
any good damper ? fluid damper ? doesn't make any difference ? why ? street, street strip, or race mean anything ?
TIA as always !

ATI 3 ring dampeners regardless :twocents
My current SP E85 motor has a ATI 3 ring on it, just like all the rest of the motors I've built in the last 5+ years, they work very well

Everybody's preference is the ATI but the Fluidamper looks more stock on a Street Hemi it that matters to you.

I have an ATI on my hemi and a Fluidamper on the 440. Both seem to work fine.

I run fliuldamper on my 416ci with a gear drive.. have been for years now

Ati. Fluidampers are HEAVY!

Part of how they work.

ATI here also with gear drive, several motors.

I have a TCI Rattler with a gear drive on a small block.

I like a fluid damper for my race engines. On a street engine, I have been told that if you run a fluid damper in cold weather the silicone fluid gets thick and may cause issues. So I just run a stock elastomer type balancer that is sfI approved on street engines.

I drive my car at well below freezing and my FD has never had an issue.

A picture tells the story!

ATI 917127E fits both Jesel belt drives and gear drives. @AndyF

Andy is a good resource for this kind of info too.

For a Milodon geardrive/super damper combo a special damper hub is requiered. $119! And don't under any circumstances buy a used damper. The ATIs may have to have all the bolt heads drilled out/off to disassemble. It might be worth asking if anti sieze can be put on the shoulders of the bolt heads before installation. I had to drill mine to dissassemble for rebuilding. I tried soaking them in wd40, penetrating oil, still broke multiple allen sockets.

interesting replies fellows. thank you !
any others ?

Every chart I have seen, even those published by ATI, shows the FD more effective for its intended design below 6500? rpm, seems like the expected use would be a factor in deciding.
That being said, I have both.

I ran my FD to 8200 on every pass with zero issues and now on my 418

The differences in dampening between an ATI and a Fluid damper are pretty small. Bracket racers would never notice the difference. NASCAR engine builders need to pay attention to this stuff though. I'm pretty sure all NASCAR engines get tuned ATI dampers these days.

For bracket racing or street duty just use whatever fits. For serious drag racing I'd probably use an ATI unit.

Finding something that fits is the important thing. ATI makes a version with a longer hub that fits belt drives and gear drives so that is one option I'd look at.

"Stop the presses

So I went online to locate the ATI graph/chart that I thought I just recently viewed in the newest ATI product catalog I got in the mail. The online graph does not jive with what I shared here regrading the comparison of ATI vs FD in rpms.

I will get a copy of ATI's catalog at PRI Thursday and I might have to retract my incorrect comment. Sorry"

So the attached pic is from the latest "ATI 2020 Winter catalog".

As AndyF has already noted there are many variables in tuning a damper. I suspect there are at least 12? known elected variables that they account for in the final design. I'd bet there are another dozen variables felt too difficult to measure or insignificant enough to design in, and I also suspect there is an infinite of unknown undiscovered other variables also at play. All to mean, pic your poison.

So I also suspect ATI being a for profit corporation, picked a specific ATI damper to best promote their marketing strategy. I'd give them the benefit of doubt and believe they did not pick competitor test example s that would test poorly.

That being said, all three dampers in the graph appear to test the same up to approx 5800 rpms, at the point their effectiveness separate, then the FD tests best, until approx 6900 rpm where its non effectiveness quickly climbs, and the ATI becomes more effective as the rpms climb. I would not draw a solid conclusion from this, but I believe its indicative in general as to the best rpms effective range a user could be guided by. Such as if you never seldom operate your engine above say 7000 rpm, the choice is rather clear. None of the above numbers are etched in stone, especially if one refers back to my opening comment on variables and tuning dampers.

Of the 3-4 balancer companies out there, their products/theory work at different harmonic levels. Some do a general dampening through the rpm range and others are more specific. I've found that harmonics, whether engine, driveshaft, etc, can be many hidden issues that surface and reveal themselves in unexpected ways. There was a chart several years ago that posted the rpm/dampening effects for balancers. Then of course is the whole 1960's-70's Chrysler/Nascar balancer theory that lets balancer weight solve all issues.

The primary purpose of a damper is to (attempt to) suppress destructive harmonic forces (not balance related). The exact design is highly dependent on the engine design and use (not the power developed), especially crankshaft stiffness. A stroker is not a stiff as a stock crank, etc.