balance / damper question

[grumpyvette]

A while back a buddy of mine bought a stroker kit for his 350. It came with a 6" external balancing harmonic balancer in the kit. This was factory new and in the SEALED box. While assembling we noticed that when we seated the balancer, it just barely rubbed on the front cover seal. We then replaced it with an 8" SB 400 external balancing unit again in the factory sealed box. This solved that problem. Then we had a guy tell us that we couldn't do that because stroker kits a special and need that 6" damper. I say that a 400 balancer is a 400 balancer and if that crank needed something different then the box would have been opened. Any thoughts?

I doubt your main issue will be damper size, both dampers maybe are externally balanced, but to what standard or gram weight/were the components designed for the same weight crank and connecting rods etc. the kit might have a 50 lb forged crank with 6" connecting rods and forged pistons , the factory damper balance was for a cast crank, 5.556 rods and cast pistons?

a 8' damper in theory should be more effective than a 6" damper, but generally a "KIT" is composed of "BALANCED, TOGETHER, MATCHED SET of COMPONENTS"
and as a "KIT" its most likely more accurate than assembling factory balanced components matched to an OEM production standard, the new dampers weight and balance may or may not fall close to the factory perameters

viewtopic.php?f=38&t=3900&p=28672&hilit=balancing#p28672

viewtopic.php?f=53&t=141&p=5391&hilit=balancing+external#p5391

 

[Grumpy]

http://www.epi-eng.com/piston_engine_technology/torsional_excitation_from_piston_engines.htm

http://www.epi-eng.com/piston_engine_technology/crankshaft_torsional_absorbers.htm

 

[NitroInjected]

I think this is a good place to post a question of this nature. I mentioned it in another thread but I am trying to get pricing asap:

I Want to run a fluid damper on an engine that never came with one. There are two issues. One is that I would need to run the serpentine or v belt directly on the outside of the damper like an oem would due to packaging. The other issue is that no one makes a damper for this motor so I would need to adopt something to fit. It would of course be balanced separately as all of the other pieces are going to be as well.

 

[Grumpy]

why not call fluid damper after taking careful accurate measurements of your crank snout diameter,
and all your current damper dimensions, maybe take a few pictures to fax over?
and ask for their ideas, they may already have what you need or can modify a similar product for a bit additional cost
For Technical Support and Product Information Call or E-mail us at:
Phone: (716) 592-1000
Email: sales@fluidampr.com
Office Hours:M - Fr 8:00am - 4:30pm EST.
If after hours, please leave a message and we will get back to you as soon as possible.

https://www.summitracing.com/parts/flu-740121

https://www.summitracing.com/parts/flu-720102

 

[NitroInjected]

mailed them this morning after my call wouldnt go through. I may have called after they were closed as I only really pay attention to east coast time difference.