I have a chance to pick up a banjo rear out of a model a. How much power would you be confortable putting to it? Im shooting for a 300hp 296 that will probably make 400ld-ft of torque Sent from my LG-K373 using Tapatalk
Hi Then why not answer him. Even I would like to know. He asked for a reason and does not need a smart ass remark Thanks Dave
A 300 horsepower flathead, and you want to cheap out with a Model A rearend? Don't. If you want a banjo rearend, use a late 32 to 48 depending on what chassis it is used in. An A rear (and early 32 as well) has an unsupported nose on the pinion.
I've run a Model A banjo behind a flathead but never been hard on it. A v8 banjo has a larger, stronger ring and pinion but the axles are the same diameter from 28 to 48 and are keyed. I wouldn't expect it to hold up if you put your foot in it. There is information around about running late model axles in them but involves machine work. Unless there is some reason you want to stay with the closed drive line there are a lot better rearends out there.
I am not a Ford guy and don't play one in TV. But My best friend in high school drove a '40 Ford pickup with the banjo rear and a 289 V8. He also ran huge real Indy rubber (In the 60s!) on the rear. I can't remember where he got that rubber but it was really wide I remember that. Anyway, when his license wasn't suspended for exhibition of speed, he was changing twisted axle shafts it seems nearly every weekend. You are pretty much sunk if you keep the stock axles in that rear. I think you would have a fighting chance if you install one of the conversion kits that adapts Ford 9" axles and bearings to that rear. Oh, and you will need to also install the open driveline conversion pinion kit. Here are photos of the conversion I did on the Mysterion clone rear; Firsts you need to get a kit like this Then you need to modify the ends of the axle housings. I narrowed my axles so cut these off the tubes and chucked them in my lathe. a machinist can do the job with the ends still on the tubes, that bore holds the oil seal, the aluminum piece holds the axle bearing; then you have to bore out the ring gear and differential housing to the diameter of the Ford 9" side gear. Seems that might be tough to do but the ring gear bores easily using carbide tools and light feed; Next you need to modify both the 9" side gears because they are too big diameter to fit in the old differential. Can do this on a grinding wheel, not critical; And also need to modify the banjo spider gears which you reuse. They have the same pitch as the 9" side gears but the teeth are a little too tall at the crown and hit the root of the teeth in the side gears. Again not critical, just grind off a little (1/16"?) of the crown of each tooth on the spider gears so they mesh and there is no binding; That's about it except for getting a set of axles and side gears from the junk yard that are the right length or have been machined to the right length.
We only assume 296 means flathead. 300hp is might high numbers. It'll have to be supercharged. Joe Abin built a 284 supercharged @ 265hp. Model A rear / wait for the carrots to snap. The 3 Spd crockery department will need to be treated gently also.
300 HP and 400 Ft/Lb or torque? You really have to write a book. (Also, you should consider a stronger rear end.)
We're going to need to see some pictures of this setup, especially the bottom end, and how you beefed it up. A V8 banjo likely will not even be of much use, if these are your real numbers. If you really want a banjo, and cannot swing a quickchange, Winters makes a non-quick change center, with a 10" ring gear. You might be able to find a used one. These have the 3rd bearing supporting the pinion head. But seriously, if you have the coin to make a 296 do that, find some to back it with a stout rear end.
Naturally aspirated, either 2x1 or a single 4bbl. Haven't decided yet. Prefer the 2x1 setup honestly Sent from my LG-K373 using Tapatalk
You know the old saying, “Ask a stupid question...”. There are a lot of posts where Model A rear axles are questioned for even just a stock 100hp Flathead swap. So,it goes to reason then that it would be exponentially more likely to grenade behind 300hp. There are MANY better choices with better brake options. I don’t have a Model A axle in my AV8 for this very reason.
A '48 banjo would would be questionable @300hp, depending on the right foot. The key way on the end of the axle is probably the weakest link. Hotrodworks has side gears that will accept 28 spline for 9 inch axles which would beef it up a bit. That leads to more work of 9" housing ends etc...
Darn, I was looking forward to seeing a 300hp flathead! Would stay away from stock banjo, but beefed up it might handle it, depending on the amount of Pb in your right foot Sent from my iPhone using The H.A.M.B. mobile app
Forget all the axle talk, this is the significant fact when it comes to A rears. In the interests of full disclosure (which a lot of question askers aren't good at), I looked up the OP's other posts and found this: "I am in the process of building a 292 out of a 1975 Chevy truck." So we won't see a wonder flathead after all.
A little research would have shown a Model A produced 40 brake horsepower at 2200 RPM's and was rated at 24 HP. Would a rear end designed for the above engine stand up to 300 hp and 400 ft pounds of torque? Thats a tough question all right.
Hi I have been on the hamb for a long time. When it crashed I could not get back on until now for some reason
Lemme go out on a limb here and guess the O.P. is trying to avoid welding on new bracketry for a new stouter rear axle. Unfortunately once you open up the hot-rod can-o-worms there are things that have to be done along the line for peace of mind and reliability. You are going to have more issues than just a rear axle by putting a very long inliner in a tiny model A engine bay without other compromises. Think firewall, cooling, oil pan to ground clearance...But on the subject of the rear axle. Someone has to have the brackets at a reasonable price to convert a D44/S10/8.8/9" housing under there and keep the geometry stock. Hit up the google and see what you find. Bet someone links info here. https://www.est1946.com/modelareaspringhangers.aspx
No blower. Its been done multiple times before. Guys have actually hit 600hp on race gas with the right head work (big valves, lumps, port and polish), an overbore, and a cam. I'm not going that crazy with mine. .030" over, propane pistons, 256/252 hydraulic cam, rhoads lifters, the aforementioned head work, balancing the bottom end, custom header, nothing too fancy. I might see it. If not 275 should be easy. And that should be plenty for an 1800lb driver. Sent from my LG-K373 using Tapatalk
I seem to recall a 600hp flathead in one of the magazines about 15-20 years ago. But they did a crazy amount of work and had a bunch of one off stuff made to get there. Sent from my LG-K373 using Tapatalk
Is the reason to use the banjo style rearend just for the looks? Or because it's cheap and handy? Be aware that any banjo that is found (except for the rareish 40's pickups) will need an expensive conversion for the open drive required to work with your new transmission. Since you aren't sticking with an all old Ford drivetrain, I personally wouldn't use a banjo in your car. I'd find an early 9" Ford, and narrow one side to center the pumpkin so it looks good under the T spring.
I agree with alchemy although I'm running a banjo and never had trouble but it cost a ton to build it right.
Many years ago in a comment to a similar thread someone pointed out that over the years a huge number of A banjos have complimented very stout flat motors in both the establishment and breaking of speed records.
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