AV8 rear axle ?

Pete Fl/Wi

Pete Fl/Wi

Senior Member
I posted this over on the HAMB but no response. I hope someone on the Barn knows about this.
I am starting a AV8 project and still in the planning stage. Goal is a traditional build a la Bishop and Tardel. I have a 30 Ford coupe and a built 8BA. I was told by a friend that back in the day a trick to get room for the engine with stock fan is to use a banjo rear end with the spring behind the axle but move the right side axle to the left of the center section and the left to the right. Which moves the spring to the front of the axle. Then you move the body back so the axle is in the correct position. You end up with more engine room and a longer wheel base. I know there are issues with torque tube and radius rods. I would be interested in hearing from others that have done this.
Thanks, Pete
 
Lots of people do mount the rear with the spring in front, like you describe, but normally in scratch built cars, or modified style stuff. If you did that, you would extend the A's wheelbase by (off the top of my head) about 8", which, in my opinion, would be too much.

If you did the axle flip, then kicked up the chassis and shortened it a bit, you could probably end up with a slightly lengthened wheelbase and it would look ok, but in reality the thing about an AV8 is that it keeps it's original wheelbase and looks great. If you want a longer wheelbase and more engine room use a 32 chassis.

Ok, I'm rambling, but I think he's kinda right, but without thinking it through and compensating for the over lengthening of the wheelbase it would be too long.

Mart.
 
Less work and better proportions just to recess the firewall a little. In fact, a 30/31 firewall can be un-riveted, turned around and riveted back in, thus creating about a 3" (from memory) recess. I have a 28 tudor sedan hiboy that cant be recessed, so I lengthened the frame 4" and put a kickup in it. In my opinion 4" is about maximum for lengthening, any more and it starts to look like a "shudder" rat rod.
 
Thanks guys, I measured it out at about 7 inches and thought the samething that the wheel base would be longer than I would want. I am thinking of a 3 or 4 inch kickup. I am still in the planning stage and want to look at options for this build.
Pete
 
I've seen a few frames that were lengthened by 7 inches to use the spring behind set up. It doesn't have to be kicked up much if any as the spring over axle approach does in order to lower the car. It does take some work to engineer the crossmember and still have axle to frame clearance. It works better with a turtleback trunk lid than with a rumble seat set up since it can encroach farther to the rear of the trunk area if the OEM model A cross member is utilized.
 
Last edited:
I am with you not wanting to cut the firewall or move the radiator. There was a thread on the HAMB on which pulleys to use along with 41-47 distributor on how to accomplish this. I am planning on using a 42-47 pickup rearend and narrow it using a mix of axles and axle housings also info on the HAMB on how to do that. I am going to cut off the perch end off of a pair of A axle housings and fit them to the later axle housings so I am not altering the wheel base or adding to the frame. Abit more work, but I like to keep the details in proprtion to what it was. Rod
 
I also went without altering my frame, I have '36 axles. Spring over with model A perch bolted on, cut down torque tube. I used existing holes in the frame, to bolt the front engine mounts and cut down '32 on. 59A engine with stock intake fits, my edmunds 2x2 needs a dent in the fire wall.
 
Last edited:
Pete, I wanted to run a stronger axle, and went over board with a bronco 9". It is sprung with a stock rear model A spring on top of the axle. I used speedway spring mounts, and Z'ed the rear of the frame to get it down. To make room for the V8 I moved the front cross-member ahead 2'', it isn't noticeable as long as it is fender-less. This also made room for an engine driven fan, and generator.
I don't have any pic's of the rear axle, but here's some of the engine. The firewall is a 32 sectioned and chopped to fit the "A" cowl. Chuck S.
 

Attachments

  • DSCF0615.jpg
    DSCF0615.jpg
    100.7 KB · Views: 53
  • my new cowl vent 001.jpg
    my new cowl vent 001.jpg
    86.3 KB · Views: 37
If you are using a banjo axle you will have to shorten it so put the axle where you want it and put the engine where you want it and cut the torque tube to the length required. I used 32 railswhich are 106 wheelbase vs 103.5 for the A and put the extra 2.5 inches in the engine compartment.
 
I would recommend locating your engine using a Model A rear axle and Torque Tube. I did that with a 59AB block and did not have to cut the firewall.

Then when you upgrade your rear end, cut some model A spring perches off of a model A axle and install and weld them to the top of your later axle.

IMG_3772.jpg


12cleanengine.jpg


CIMG3241.jpg



attachment.php


attachment.php


attachment.php
 
Look at Jason's post and consider this...an 8BA with normal hardware is substantially longer than one with 1942 type distributor and early single pulley setup. The difference is enough to eliminate most of the problems.
When you build the 8BA, get am early cam, 1942 distributor setup, '37-48 pumps, and generator with fan mount. Any '40-48 crank pulley can be readily cut to single sheave.
This not only knocks several inches off of the front, it gives a cheap ignition upgrade.
Add in earlier heads and you've converted the whole look of the 8BA to early hotrod.
Only very minor hole plugging is involved in pump and head swap, all else is routine assembly.
 
I have an 8ba in my 32, which affords a little more room then your A and I'm struggling making the mechanical fan work. You may want to concider a 59 cam, dizzy and water pumps. Every thing will be a little closer to the block that way. I kept mine all 8ba and hope I have it licked this weekend.
 
I see some are flipping the axle tubes to mount springs in front of axle centerline.

I did that many years ago using 49 Olds trailing arms with the big pivot bushings. I then mounted springs (coils) ahead of the axle too.

My reasoning for doing this was to clean up the rear as best I could.

This seemed to add a different ride factor and it seems to me that the spring forward the axle would act something like a fulcrum. Axle goes up, front of training arm would try to go down, resulting in a more level ride.

Anyone considered the effect of this and have an opinion.

Thanks
Jack
 
Using the 32 frame (original or repro ASC rails) is the best way to go. Unless of course you are running fenders ( we don't need no stinking fenders!).Everything bolts in or close to it. As a bonus a Model A on deuce rails always commands a higher price when you sell. On my 8ba we used an early style fork type generator with wide belt truck water pumps from Speedway. We cut the front pulley off the original 2 pulley set up. I made up a 2 inch spacer to mount the generator and it all fits with 1 belt. No clearance issues with the radiator but we did notch the front xmember just a leetle.
 
Here is where I am on my build. 8BA already done. 39 trans, 40 rear, Model T gas tank, 2 4inch and 2 5 inch wide wheels on hand. Frame is on order with 3 inch kickup.
Body is coming off next week when my son visits. Orginal frame, engine,trans and wheels are going to a Model A friend and he is going to put a stock sedan body on it. I got this interesting item on e-bay thought I would use it for a fake quick change.
Pete
 

Attachments

  • 0612131546-00.jpg
    0612131546-00.jpg
    103.7 KB · Views: 56
  • 0612131546-01.jpg
    0612131546-01.jpg
    73.3 KB · Views: 39
You must log in or register to reply here.
Back
Top