Hey guys, and gals
So here is the story. I took out my bad ass little 289 and built a 427 stroker from a 351W. The crank, fly wheel, pressure plate, and harmonic balancer were all balanced together, and then balanced again when they had to shave off some of the counter weight from the crank so it would rotate in the block correctly. So there I am with my big bad 427 stroker, and it vibrates like an SOB at about 3500 rpm's and higher. Below that it is fine. It does it in gear, out of gear, clutch in, clutch out, moving or not, running or not (just making sure you were still with me).
I had a couple of thoughts.
1. Motor mounts, but on visual inspection look fine, they are the stock mounts
2. Too small of a carb, total pull out of my butt guess, could it be causing "lean misses"?
3. Vaccum advance not working properly, hence the problem above 3500 rpm's
4. It is just that freakin bad that nothing can stop it.
Truth be told I don't know. Hope you can help?

So here is the story. I took out my bad ass little 289 and built a 427 stroker from a 351W. The crank, fly wheel, pressure plate, and harmonic balancer were all balanced together, and then balanced again when they had to shave off some of the counter weight from the crank so it would rotate in the block correctly. So there I am with my big bad 427 stroker, and it vibrates like an SOB at about 3500 rpm's and higher. Below that it is fine. It does it in gear, out of gear, clutch in, clutch out, moving or not, running or not (just making sure you were still with me).
I had a couple of thoughts.
1. Motor mounts, but on visual inspection look fine, they are the stock mounts
2. Too small of a carb, total pull out of my butt guess, could it be causing "lean misses"?
3. Vaccum advance not working properly, hence the problem above 3500 rpm's
4. It is just that freakin bad that nothing can stop it.
Truth be told I don't know. Hope you can help?