markmine
Active Member
Hello everyone.... I hope someone can give me a few ideas in trying to fix the vibrations in my 340 before I loose my teeth driving to the next cruise night! I purchased a '72 340 for my 73 Roadrunner from a guy who said he rebuilt mopar engines for 30 years. The engine is freshly rebuilt with a forged crank. I installed the engine along with a new McLeud zero balance flywheel and new clutch. Problems started when I first started the engine, the lifters were LOUD and the engine vibrated big time! The guy who built the engine said this is normal! After about 100 miles, I couldn't take the lifter noise and upon further investigation, the rocker arms looked like they were incorrect (looks like big block rockers?). So i replaced the rocker arms from the 340 I removed from the car, lifter noise resolved and the engine seems a little smother, but I still have the vibrations that vary at different rpm's. So I removed the McLeud flywheel and replaced it with a stock neutral balance, still have vibrations. I removed the dampner and it did not look like the dampner on my 340? So I checked Galen's book and the number on my old 340 dampner is the correct one for a 340 forged crank engine, so i installed it and vibration still exists - but better. At least I can drive the car now and get the RPM's up to 4k without fear of destruction. Anyone have any ideas... Thanks!