The end of November I ordered and installed all new, OEM (not cheap-ola stuff) engine and transmission brackets and mounts, including new bolts. Unfortunately, my annoying vibration still existed, so the root cause isn’t likely the mounts. I suspect that the new mounts are a bit stiffer, so whatever is causing the vibration was enhanced at all RPMs. It was more pronounced at idle too. This vibration is present whether or not I have my Panzer Plate installed, so it’s not that.
To make matters worse, I was forced to buy a new battery the day I got everything back together. The one I had was 7 years old, was dead when I put it back in the car, and would not take an overnight and all next day trickle charge.
I was re-reading what Franko6 wrote on Nov 15 and Nov 19. He wrote, “I have seen an engine that wasn't suspended equally from both side engine mounts cause vibration issues. Once the vertical engine mount bolts were loosened and the engine centered on the side mounts and retightened, the problem went away.” When I installed the new brackets and mounts, I did the engine side first followed by the transmission side. Therefore, I didn’t have all four vertical bolts loose at the same time. I did ensure that there was no load on the mounts when I tightened to Franko6's recommended 65 ft‑lb for the 12‑mm bolts and 45 ft‑lb for the 10‑mm bolts, and I made sure everything was lined up as Aaron Growler had suggested.
Back in September, I removed the serpentine belt (and Panzer Plate) and carefully drove around for a few miles. The vibration was still there, so it's not likely the power steering pump, alternator, A/C compressor, serpentine belt tensioner, or roller.
I emailed Franko6 about my findings after the mount and bracket changes. Franko6 indicated that he was inclined to think since this problem happened during a timing belt installation that perhaps I would go through that timing belt procedure again. It wasn't something that I wanted to hear, and Franko6 indicated that if a timing belt change still doesn't cure the issue, then I think I should just try to get used to the vibration.
I broke down and purchased a complete timing belt kit from a different vendor than the one I purchased from in June (belt, rollers, water pump, tensioner, bolts) and installed it Friday and Saturday morning. Though the vibration might be a bit reduced, it's definitely still there. So, another waste of time and money. Ugh and Grr!!! The bright side is that if I still have this car at 230,000 miles (8 - 9 years!!), then I'll have a timing belt kit already available.
At one point a few months ago, Franko6 and I had a telephone discussion about the DC Stage III+ Clutch and Lightened 17.5 lb. Flywheel that I put on my car in 2009 (I can’t believe it was that long ago). Franko6 had indicated that he didn’t like lightened flywheels because that are often far out of balance via his testing. So now I’m wondering if that is the root problem of my vibration issue. If it is, then I find it odd that after all these years a problem would creep up now (or maybe and more likely I’m just noticing it more now with new mounts and dogbone), and coincidentally right after I performed a timing belt change and camshaft swap in June.
My dad is a Ford guy and former mechanic several decades ago. Today, I was explaining my issue to him and before I even told him about the clutch system he says to me, "Sounds like you've got a flywheel balance issue" and told me about his prior experiences with guys installing the wrong mass flywheels on their modified Fords.
Oh man!! Why I didn't talk to my dad about my issue months ago, I have no answer. Probably because he's not that enamored as I am about owning and driving a Volkswagen diesel. So, maybe in the spring I'll consider a new clutch kit with a full 21 lb. flywheel. I can't do it now with Christmas here and the cold weather. Besides, I really need a breather from continuously diagnosing and working on this car. I certainly won't look forward to dropping the transmission a fourth time. We'll see...