Hello All, I have a 30 coupe and I'm close to completing a AV8 swap with a 50 8BA, 39 Trans, F1 cross Member, etc. I have a 40 Banjo for the rear end and it's about 1 inch wider than the stock Model A rear end. Can I run the Model A rear end? I'm sticking with the torque tube, and it looks like everything will mount up good. Can the Model A rear support the extra HP? I'm running bigs and littles with some skinny bias plys, so I don't think it will hook up and cause too much force on the rear end. I would like to understand the value of using the 40 banjo and understand if I can use the Model A rear end without issue, until I get the other one cut down. Thoughts? Thanks and Regards- Chris
first off, yes you can use the model a rear. do you want to ?? probably not. the A rears pretty much started at 4.11:1 and went from there! way to low a ratio for the most part. also the A rear has no pinion support. it really can't handle more than the banger has to give. you are also stuck with the stock height in the rear with the stock rear. the 40 rear gets you spring behind the axle. this lets you lower the car quite a bit in the back.
The model a rear is not quite as strong as the V8 rears, but it will most likely hold up fine behind that 59AB. My buddy Joe has a 32 3 window with a 4 carb 8BA that still has it's stock early 32 rear in it (same as model A in the center) There are several other guys on here who have used A rears behind Flathead V8's. At the end of the day, it's up to you. Sent from my DROID device using the TJJ mobile app
I am because I haven't built my 36 rear with quickchange yet. Agree with revkev on the gears. The engine is screaming at 65 mph. It's not going to fly apart or anything. Lay off the burnouts and you'll be fine, until you can't stand not having any top end.
Oh yeah, I can't say for certain, but I believe there were just as many 3.78 model a rears as 4.11 Sent from my DROID device using the TJJ mobile app
And you can also buy a 3:54 ring and pinion and a 3:27 ring and pinion for a Model A rear... It's just money..... http://www.brattons.com/prodtype.as...ition=11&ph=&strKeywords=&&strSearchCriteria=
I have a Model A behind a flathead. Has worked fine for me but I also have not beat on it. It has been used for years. I don't know what the gear ratio is but I can run down the road at 70 but the motor is running up high on rpms. I have a tach in it but don't remember what rpms I run it at. I am thinking around 3000. Neal
Would really like to see how you put the 8BA in your coupe. I am doing the same thing with my Roadster and I really don't want to cut the firewall if I don't have to. Did you use a mechanical fan or an electric???
My old channeled 'A' Coupe had a 5/16" by stock Ford 59 A-B, '39 trans, Model A rear, 3.78. Built it for a bud in 1958, he sold it, then I bought it from the second owner. Ran it at Fremont drags for years, street duty, back and forth from San Jose to L.A., 8 times or more. Broke some axle keys, once fractured a spider gear. Replaced it and a carrier bearing, rear was good, tight and quiet 'til we pulled it in exchange for a '40 rear. (1963) I was light on the clutch pedal, but the car was always in the low 90s at the digs...
If your really worried you could weld a bung on the axle housing and thread a ring gear support snubber in it to help it a little tk
I ran the stock rear in my old coupe, it had a pretty warmed B that would keep up with V8's and I drove it hard. I had stock 3.78's in it, it would do 70 pretty easily but 60-65 was a good cruising speed
Thanks for all the feedback guys! I will post Pics soon. I'm keeping the 40 Banjo and it will go under it within a year or so. I just wanted to make sure there wasn't some huge "issue" with the A rear end, I was missing. Sounds like it should be OK for the time being-
I didn't have to cut into my firewall at all. The fan is a Generator Pulley/Fan, so mechanical. She's tight, but it fits without issue. I didn't want to run electric and try to leave it as "period" as possible, plus it's still 6V.
Search for a thread by Gashog. Never mind, I found it. He uses a Model A rear end. http://www.jalopyjournal.com/forum/showthread.php?t=238505 As stated above by tub in da dirt, a bronze snubber can be fitted to a Model A rear that stops the crownwheel "walking" under hard acceleration. I had a Model A rear in one of my rods in the 60s, held up to abuse ok. It was 3.78
The A will likely be fine unless it is real loose from wear. Most were 3.78 like the '40, but check. 4.11 went into some (as well as some '40's...) and that is getting pretty low for a car with no overdrive. If you have a decent A rear, there's also not much to lose...converting later to a '40 is going to be the same kob as now.
Is the Model A torque tube the correct length for your engine/transmission combination and location in the frame?
I had my car all set up with the v8 swap and the factory a rear axle... I decided to go with a 40 rear just because the brakes
If you are using a 39 style transmission with the two feet on the back of the trans, and a flathead and a Model A frame, yes. The Model A rear and torque tube is perfect, and no cutting the firewall or moving the radiator. It's pretty cool.
Rear tranny mounts to the torque tube. Needs a 1/4 inch-ish spacer made to keep from pulling the rear forward.
The 39 tranny will bolt to the torque tube. Need to make a 1/4 inch spacer to keep from pulling the rear end forward.
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