383 damper bad?

[toolmonte]

I have an external balanced 383 trying to figure out bad vibration after a t-56 swap. After fooling around quite a while. I watched the damper while car was running on lift. It has quite a bit of wobble between inner and outer rings (stock gm) the rubber is also squeezed out different amounts around the damper. I assume this is causing my vibration and am going to replace it. What is the best damper to put on it. Motor sees 6500 rpm max Street car with dreams of track time. Thx Jamie

[MonzaRacer]

Order up a performance balancer for a 400 sbc Or Dorman number 519-016 Napa number 600-5203

[TheJDMan]

Any time you see the outer inertia ring wobbling on a balancer that is never a good thing. This is what normally happens with generic no name balancers as they age. I have used both Professional Products and Fluidampr for many years on numerous street and race engines including my current 383 with no problems. Which ever balancer you decide on, I highly recommend you go with an SFI rated unit, not some cheap generic NAPA unit. My 383 is internally balanced but for your external balance motor this Professional Products would be a good low cost choice.

http://www.summitracing.com/parts/pfs-90001/overview/

Fluidampr is a viscus fluid design which works over a wider frequency range and provides better protection on long stroke engines but is more pricey. This same technology is used exclusively on huge commercial diesel engines where maximum reliability is a primary requirement.

http://www.summitracing.com/parts/flu-80251e/overview/

[MonzaRacer]

Personally, after tearing down numerous engines I would not use Fluidampers on my worst enemies engine or for door stops. After seeing bearings that all looked like they had sand ran through them I will pass on them. Built 4 engines, all same, EXCEPT two had Fluidamperrs two had ATI Super dampers.
The ATI equipt engines bearings look perfect, Fluidamper equipt bearings looked like hammered a$$.
Just my thoughts, opinions, experience.
If it's external balance, order up a balancer for an early 70s 400, performance or stock , slap it on, and drive.

[another69]

If the vibration started after the t56 swap is it possible that you have the wrong flywheel? If it is external balance than the flywheel should be too. The way you describe the damper I would start with that though to rule it out. Besides it sounds like it may go at any time!

[sanman]

I have the TCI Rattler on a ZZ383, It works great.