I Have Been Shafted

Based on the title, this story is not the vulgar thought that you may have; instead, it is the design action that was taken on the Bluebird. Let me bring you up to speed. The Bluebird is my 1962 Pontiac Catalina restomod that I have been building since I left high school in 1950. (At least it seems it has been going on that long, rather than the actual three years since I started the project). Does it run? Oh yes, it runs like the hammers of hell if you step on the gas. The problem is not if it runs; the problem is how it runs.

This adventure began when I first put the Bluebird on the road with the 3:40 Auburn racing differential. It runs great except for the banshee howl at 30 mph. That howl is not a good accompaniment for the really nice sound system that is installed. Imagine playing a Beethoven symphony in the woods sitting next to a wounded wolf – this required a remedy. I thought it must be a bad unit, so I got another ring and pinion set, but this time with a 3:90 gear ratio. Good news – it no longer had a howl at 30 mph. Bad news – it now howled at 50 mph.

Dave Fitzgerald has worked on the Bluebird getting the body panels nice and straight, while also curing the incontinence of the Vintage Air system. I think Dave felt that I must be a dumbass when it comes to setting up a differential. In all fairness, this is probably not a bad assumption. Dave suggested letting his colleague Ray do this work as he has been installing differentials since I still had a full head of hair. The first idea was to ditch the Auburn ring and pinion, which has extra big teeth designed to take 1000hp and use another manufacturer. Some research revealed that the Auburn ring and pinion was the only game in town for that limited slip design.

This is fully documented in a special published manual that details exactly how it is built, and how to set it up. So let’s ship it to the author’s shop, let him set it up, and also try another gear set. Turns out he found a lose phramus nut (and a couple of other things), set it up perfectly, and then returned it to Dave and Ray, who installed it. In the process, they discovered that the pinion angle was extreme and might account for the vibration I felt when driving. This required me to fabricate two helm jointed rods to change the pinon angle. John Cimbura kindly handled that task for me.

Were we on the right track? Well, the rear end still howls, but at a lower decibel level, and the vibration is less and only occurs on deceleration. Conclusion: Consider the new lower decibel howl to be a charming aspect of a high-powered vehicle that accelerates straight as an arrow. But the vibration needs more attention.

The driveshaft balance was a suspect in this situation, so Dave had Bill of Englewood Driveshaft, a premium shop, come out and inspect it. Bill said the driveshaft was not only way too heavy, but also a bit too short, and I should have an aluminum driveshaft. So I got shafted by Bill and a lot of the vibration went away. At this time, Dave gave the car his highest compliment: “I no longer hate it.”

Dave and his mechanics put over two hundred test drive miles on the Bluebird and made no mention of vibration. When they drove it, the car had Y rated Michelin tires on it, which are good for 186 mph. I drive South Broadway at 25 mph and have no intention of outrunning cops, so that rating is ambitious. To get the speed rating, I think the tires have very stiff sidewalls, which are matched by stagecoach wheels and cause the car to ride as if on a rough road. I changed the tires to Michelin Defender, which I like very much; however, there is now a high speed vibration. Please tell me this is just due to tires that need to have the balance redone.

So – three sets of ring and pinion gears, two drive shafts, two sets of tires, and two gas pedals all replacing parts that were brand new. The Bluebird is dangerously close to becoming the Boobird. The beat goes on! I will not surrender – only go broke. Stay tuned.

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