I'm gathering parts for a '31 Model A build, powertrain will be a 346 Flad Cadillac backed up by a '37 LaSalle 3 speed. The engine has Edmunds aluminum heads and an Edmunds dual deuce intake with a pair of Carter WCD's on it. Stock cam and exhaust manifolds, Egge stock replacement pistons, .020 over. Not a screaming hot rod motor by any means, but should have plenty of torque to push the car well. I've got a couple choices for rear axles, including an Olds 9.3 inch, an 8.8 Ford, and a banjo rear which I believe is from a 47 pickup. Is a banjo rear from the late 40's going to be adequate, or should I look at one of my other options? Thanks!
Plenty of Banjos have been used behind similar setups since the golden age. Should be fine as long as you stay away from clutch-dumps.
Banjo is OK if you like screaming engines at 50MPH, keep a few axle keys handy and learn how to replace them. Stay with narrow tires and avoid speed shifting. The 8.8 is probably the strongest of your choices and will handle 400+ HP all day long.
All depends on the ratio of the banjo. 3.54 gears like the highway all day long. My personal favorite is 3.78. Nice combination of driving around town and road miles. If you're breaking axle keys you're doing something wrong. If a banjo is set up right they are totally reliable and just plain cool. Guys who don't like 'em have never took the time to sort one out properly. They will not take brutal horsepower but as Rainer****** said they work just fine. The real question is what ratio are the other rears and the details of the car you're putting it in. I like closed driveline banjos for a lot od reasons. Just remember... skinny tires and torque the axles to 200 ft. lbs. min. and you'll love 'em.
Thanks for the feedback folks. aaggie, you really think an 8.8 is stronger than the 9.3 Olds that used to be found under pretty much every drag car in the early 60's? If it is, then it's a no-brainer, because it's quite a bit lighter than the Olds.
I think if you do a search, you will find a lot of info on how the old timers made the banjo rears hold up to quite a bit of power. Guys like Chrisman running hemis in A sedans, Ohio George with a blown Cad then blown chevy in his Willys etc... Some lapping of the axle stubs to the hubs, hardened keys, a br*** blocker to keep the ring gear from flexing etc... and you have a decent rear. I don't think the flat Cad is gonna be a killer so long as you drive it properly. As far as the 8.8 being stronger than the Olds/Pontiac 9.3-I'd sure be surprised to see that. Never seen a 8.8 behind a blown 417 on nitro. The only thing making a 9 inch Ford stronger than the Olds/Pont is the rear support on the pinion. 8.8 is probably plenty strong in your application however.
I am using a banjo rear in a couple of builds right now, but not because they will work well behind a powerhouse motor. They look cool and are period correct for the type of rods I am interested in (50's style builds). If you are concerned about what power they will take, may be best to use a more modern rear axle like a Ford 8 or 9 inch.
Banjo will b fine. My pops has a 40 sedan with a sbc hooked to the original running gear, hes always dumping the clutch and hasnt broke it yet.
This comes up often from those who know. A really snug fit of the axle tapper/hub taper is at least as important as the keys if not more. Those hubs can be hard to get off because they are put on really, really tight. A lot of issues are traced to poor taper fit and not tight enough hubs. The torque setting is way over 100. Might be as high as 175 ftlbs. Fuzzy brain.
A piece of square screwdriver makes an excellent axle key, but sadly the next weak link is the axle breaking!!
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