340 crank with 318 harmonic balancer?
The reason I asked about the casting number is the 318 and the 340 use the same casting numbers even though they were balanced internally different.
I bought it off another member on this site years ago. It is definitely a forged crank and he said it was out of a 340.
I'll be giving the engine shop a call come monday and see what he did to balance them all together. Sounds like I'll end up having to pull the engine like you said.
This is annoying.
I started building this car when I was 16, and I think had the engine work done a couple years after that. So I was leaning heavily on older dudes that "knew what they were doing". And I only got the thing drivable 3 years ago or so. And have barely drove it. I replaced a transmission mount and that's when I really started to notice the vibration. The new mount was a touch taller than my other, and I dont think it put the trans touching the floor board, I had wondered if it did and that's what caused this vibration. It also only does it while driving. It doesn't just sit there and vibrate while iding or revving. (That I can tell, it idles and revs nice)
That's what made me create this post, because I have several suspicions of the cause, but even if the trans was touching I dont think this should be a vibration that exists.
But I know even idling and revving without vibration isnt proof its balanced.
Sounds like engine shop time.
