[Huskinhano]

I'm more of a late model guy myself with my 66 Mustang. My friend is starting to build a 29 body on a 32 frame. The frame is an aftermarket, I don't know which one off hand but it's designed to mount a 29 body on it. From the start my buddy was going to use a S10 rear axle with coil overs, so he had the frame built this way for him. Now he's decided to take a different path and go for more of a traditional look. He wants to use a 40 rear that he may be able to get cheap along with a model A rear crossmember and buggy spring. He was thinking about splitting the wishbone or I should say have to because he plans on running an open driveshaft (he plans on using a 59A flathead with a T10 4 speed). He's asking me about how and where to mount the wishbone once split. I'm at a little bit of a loss but I was telling him this may take some thought in doing so from a geometery stand point. His plan was to heat the rods to bend them out and use tie rod ends. He was asking if he could mount or locate them on the inner rails of the frame that go toward the transmission. I was thinking that the center line of the rods or arms should be on the centerline of the transmission and add some extra support to where they would mount on the frame. TIA!

[F&J]

If he is using the enclosed driveshaft from the older Ford cars, then it won't work if you split the bones. That original design allows one rear wheel to move up or down without binding the other side. If you split the bones way out, then both rear wheels will try to react the same....and it puts way too much stress on the attaching points of the bones as well as bending the bones.

The easiest way to see this problem is to fab it all up but without the spring. As you lift one wheel the other will try to lift at the same time.

If you use a modern open driveshaft, then the stresses are still the same, plus the bones won't be strong enough to handle a hard launch.

A front I-beam can twist easily with split bones, but a rear end housing can't twist, and that is why the stress gets transferred to the split rear bones.

[OneMoreTime]

What to do is to get what we call a Monoball and mount it just under the front u joint and attach the wishbones to that..Keeps the original configuration intact..just shorter is all..You will need a panhard bar with this and as far as the springs use what you want..

Sam

[Huskinhano]

Originally Posted by OneMoreTime

What to do is to get what we call a Monoball and mount it just under the front u joint and attach the wishbones to that..Keeps the original configuration intact..just shorter is all..You will need a panhard bar with this and as far as the springs use what you want..

Sam

I like that idea! I would have to agree that the monoball is the best solution from a design standpoint as well. If he's going to run a buggy spring and if he does the monoball, wouldn't this keep the axle located and not need a panhard bar? I would think the panhard bar would fight the buggy spring and visa versa. Just wondering if eliminating the torque tube, will the stock arms be strong enough to coupe with the torque reaction of the axle and braking forces?

[OneMoreTime]

I missed the buggy spring part... so no panhard bar should be needed..Those arms are fairly strong so I do not see a need to change them..Unless there is a design or packaging difficulty..

Sam

[35WINDOW]

Do you know how much Horsepower your friend is going to be running? Those old rear ends don't hold up to much-something to consider-

[Huskinhano]

Not a lot of power. My friend is going to keep the flattie real mild and not going to run huge tires. It's mostly going to be a crusier. The car will be relatively light anyway, so not too much HP is needed to make it feel lively.

[OneMoreTime]

I am not all that concerned about the strength of an early Fod rear..provided it is in good condition..it is the basis for the Halibrand quick change and I know they hold up well..Note" the Champ Car rears are based on the Ford truck version with a 10" ring gear..

Sam

[Youngster]

Being an after market frame, I assume it has a center crossmember with legs going for and aft. If he were to mount the rear bones to the rear legs as close to the driveshaft as possible, I can't see any problem with using the '40 bones with tie rod ends in them. Pete and Jakes chassis have been set up this way for years.

See ya, Youngster