One quick fix is adding a bit of flywheel mass. The race car can idle right down, RPM wise but with no flywheel, it shakes the trans so hard you hear it above the considerable exhaust note. So, the idle is set at 2,200 RPM. Seems real happy there and makes no trans noise.
The missing rotor looked like flywheel mass to the system. So removing it raises the RPM where one of the nodes is peaking.
The BD-5 article is a must read for all builders, just to get the hair on the back of your neck standing up.
Bill and Lynn,
Thanks for the pointer to the article. Indeed, it's interesting, and gets your attention.
I had wondered if a flywheel of sorts would be needed, but with the high weight of the engine now, I'd hate to add more weight. It would make an interesting test, if I could do it easily though. Perhaps some evenly matched weights could be added at the 4 bolts that hold the flex plate to the drive plate. I'm not sure if you could put enough weight there to really matter though.
This will make a really interesting project, and perhaps another good use for the dynamic balancing equipment. It's all going to have to wait until the RV-8 is flying though, because that's my only priority at the moment. My goal is to have it flying by the end of the Summer, so maybe I can get back to the single rotor project then.
Cheers,
Rusty
PS- Tracy, can you send me the dimensions and durometer specs for those dampeners?