Hot Rods Need some help/direction on Model AA build

Sorry haven't posted in a bit. The model AA has been on the back burner but I actually did a small amount. I bought two 39/40 Ford front springs from speedway. I removed the old rear springs and mocked up the speedway springs. The speedway springs are only 2" so I need to make new shackles and of course rear mounts, but I am satisfied this will work. I'm using an explorer rear axle.

Haven't gotten to the steering yet

 

Looks good and like that option!

 

The tough part was the stock springs are an odd length- about 35" long.

 

Hi Everyone- Back at it finally. I finally made some progress. I machined some bushings for the front spring hangers and welded em up, made a 2 inch lift block (may adjust this after I have some weight on the frame) and welded the spring mounts to the axle. I have the axle sitting at about 4 degrees currently. the upright parts in the photo are just temporary until I build the lower mounts.

Originally I was going to use the same idea as in Osage Orange post with the lower bar of a 4 bar set up for the lower mount. I know I am probably overthinking it, but is this sturdy enough? Im imagining the axle being able to twist like this as the spring flexes. The truck will have a SBC with not more than 300hp. Maybe an occasional burn out, but not planning to abuse the truck. My other option would be a more solid mount bolted to the axle (like a hairpin?) with a front mount that moves. for sure that wouldnt allow roll but maybe is overkill. If the single bar is sturdy enough, I may buy a set of C4 Corvette adjustable strut rods for this purpose.

Lastly- Angle of the rear mount. I have seen online where many people say it should be flat with the axle centerline, but I am thinking the lower bar should be on more of a similar angle to the original wishbone. Again referencing Osage Orange pic- the lower mount appears to have a slight angle almost matching the spring.

 

Keep hacking away. You'll get this on the road before I can get mine going. These are trucks, so we should never expect the ride and handling of a roadster. The fun should still be there, though. And because of their bigger bones, real hotrodding takes place when we build them, because most suppliers don't have the cookie-cutter solutions ready to ship as soon as you give them your credit card number.

 

Looking good!

Since the last time I chimed in here, I started my own AA build. I'm going for a bobbed express look with mine.

What I did to get my rear stance where I liked it was to section 13" out of the middle of the frame and cut the back end up to stack on top of the rails. Then I made a rear crossmember to hook up to a 47 banjo & spring. That will hook up to a 265 SBC/TH350.

The roof of the unchopped cab is now sitting at about 5.5' but I still need a dropped axle up front to get the stance just right.

https://www.jalopyjournal.com/forum/threads/my-hot-rod-29-aa-express-aav8-build.1124353/

 

Yeah, the axle is going to want to rotate the pinion up under acceleration, and there's not much with this setup to resist that. But I think maybe a pair of slapper type traction bars might just do the trick. I wouldn't go with hairpin style radius arms, the parallel springs will give a much better ride and handling.

 

Thanks for all the feedback everyone.its my first suspension build so just trying to get it right.

Maybe hairpins is the wrong word. Maybe split wishbones is what I mean. Something like this picture ( but maybe not so spread apart where they mount to the axle)

 

I personally think the spring on top acts as a top link in a 4 bar, the addition of a bottom 4 bar link should not have any difficulty handling the torque of a mild smallblock....especially if you don't use giant sticky tires.if you want to increase the torque you can apply without getting a serious amount of pinion angle alteration make the bottom mounts off of the rear axle longer ( closer to the ground) thereby decreasing the number of degrees the axle housing can rotate with the same amount of rubber bushing compression in the lower links. I also should point out that if you were to run the " ladder bar" type axle locating links you showed in the photo along with the spring being fastened to the frame and the axle housing you will incur a bind since you will have two links swing on substantially different arc's try to locate the rear fore and aft .....

 

You are right. The original suspension had a wishbone mounted solid to each side of the axle and then mounted centrally further up the frame so that was along my lines of thinking, but I made a crude cardboard model and it absolutely binds unlike the "4 link" method. Weird- I guess the rear axle just didn't move much with the huge original springs.

Picture of my model, its crude but proved your point. Even when moving the front anchor points I couldn't move that axle much at all. The other one moves all over free as can be and kept its pinion angle.

Looks like I'll be making a radius rod to mount below the axle like previously suggested.

Thanks for everyone's help and suggestions!

 

Man, I think if you just copy @osage orange here you will be good to go. This is a simple setup you can make yourself.

 

Yup! That's the plan!

 

Hi everyone.
Finally a day that's not sweltering here so I'm trying to work on this some more. Take a look at the attached hed picture. With the spring mounted centered the front spring shackle is tipped forward. I assumed I will need to move the bracket for the front shackle forward so it is straight up and down, but wanted to check if it's really needed. I have seen a lot of trucks that have them tilted but those are regular leaf spring set ups and not cantilever like this. Not sure how it would effect the suspension.

I'm thinking safe side it move them but looking for input before I start cutting rivets