Aubrey's 62 409 goes 11.067 in C/S

[ss wannabee]

I think Aubrey's trying to get the Bubbletop into the 10's WITH the 10-bolt if he can. Wonder if dropping down to 4.88 would give you any strength and not affect the tune-up too much? 12-bolt is probably the way to go long-term...I think it's legal now...didn't that '62 Vette Stocker in Div.1 have one aboard a few years ago when it came out? But the Bel-Air would loose some of it's coolness if the rear was swapped, LOL!!! I'd check the 10-bolt banjo housing when doing repairs to make sure it's not distorted any...isn't it basically sheet-metal? Wonder if a little more clutch work would allow the 10-bolt to "live" a bit longer? While we're on the subject, would anybody know how many '62 Bel-Air Bubbletops were built...do I understand about 5900....and about how many were ACTUALLY 409 factory-equipped??? I've heard some of the stories about the '62 Indy Nats, and the late(in the model year) release of the aluminum front-ends and Z-11 parts upgrade and some of the racers 'borrowing' Bubbletop pieces (or cars) from rental car agencies...or so forth...All I can say is WISH I were there! Must have been a wild time!!!!

[Tony Janes]

The 10 bolt drop out is a waste of time if he is serious. It will break almost every time he goes to an event. 12 bolt 35 spline spool and axles next step.

Aubry,

Your car makes me smile! I'm glad to see that you’re getting it there. Don't listen to the naysayers, you've got a plan that is working stick with it!

Jackie McCracken

[Ken Haase]

Aubrey, your BelAir was undoubtedly the crowd favorite at Mission. And I'd bet those fans were plenty disappointed when the rear let go. But, not nearly as much as you were! I don't think Tony Janes is being a naysayer. I think that he is giving very good advice. As far as 'cool' goes, the only people that will know there's a 12 bolt under there are you and whoever wants to get down on the ground and look. IMO, cool is those disc brake mounts you made. Those were an upgrade, and a smart one at that. I understand the reluctance to give up on the original 'chunks'. But, you're making good power, you've got a fairly deep first gear, and using a clutch. Recent history proves Tony's point don't you think? When you stage at the next race you go to, you're going to have that nagging little voice saying "is it going to break again?" With a 12 bolt there's more ratio selection, parts availability, and the strength factor. Just another smart upgrade.

Personally, I want to see that car go rounds, not be towed off the starting line. No rear is bulletproof, but you would really improve your odds. Best of Luck.

[Greg Reimer 7376]

Ken is exactly right. Also,the collector/restorer's demand on the early rear end's parts availability has the cost of those units up to where a good 12 bolt isn't that costly by compatison.We all want to see that car go rounds,this would help it immensely. Bring it down for Winternationals some year!

[Geerhead55]

Aubrey,,,,sell off one of your other "hotrods" and slap a good unit like a Moser 12 bolt under there with the spool/axle/ gear ratio package you want.You can even get them with disc brakes. I had one question I forgot to ask you last weekend,,,are you running a 2 piece driveshaft? I think those cars came that way did'nt they? I'm curious how they make them live under a heavy car with a lot of power and a manual transmission,, and if you have to beef up the carrier bearing.
Good luck,,,I hope to see you again out there somewhere,,,,,,,,Danny Durham

[Grant Eldridge]

Congratulations, Aubrey, great meeting you at Mission and seeing your car run! I raced 409 Chevys in the '60's when we were lucky to get into the 12's with the track prep and tires of the day. We broke dozens of those old rear ends, as well as the axles, driveshaft centre bearing supports, u-joints, clutch linkages and of course the old Muncie transmissions. With todays tires and traction I can't imagine attempting to use that rear end. We even broke the pinion right out of the carrier on one pass, hanging off the end of the driveshaft with half the casting, the rest still bolted into the car! The chevs were bad for not upgrading the rest of the driveline to handle the bigger motors, this was essentially the same rear end found in six cylinder cars, They bolt right into the early 4 cylinder Novas even! We did improve the situation by heat treating gear sets to soften them, as I recall from 40 years ago they were about Rockwell 62-64 and we drew them down to about 52-54 from ancient memory. That made them wear out faster, but less likely to break. We'd also set the gear pattern on the drive side well towards the inside of the tooth and use as close to zero lash as we dared. The case and carrier deflect substantially and the pattern shifts out on the tooth, so if you start centered you'll move out and break the teeth off on the outside of the ring gear. I recall guys using steel straps machined to fit on the main caps to strengthen them and longer bolts. I even seem to recall some guys brazing up the end of a bolt and threading it in through the side of the case so it would contact the back of the ring gear somehow to help stop the case from spreading, not sure of exactly how this was positioned or if it was effective. The point is exactly as Tony Janes said, it's junk and a waste of your time and money to attempt to keep it in one piece. Even if it were an automatic, it would be highly doubtful that it could be reliable. As others have posted, the 12 bolt should be no problem to rework with suitable mounts, etc and you'll be saving yourself endless problems with the old 10 bolt. Anyway, best of luck! It's a cool ride!
Grant Eldridge
E/SA 6650