model A spring attached to a 32 front axle

[skryla]

I am putting a 32 front axle under my Model A. I am planning on using the original model a spring. I'm using stock 32 perches with 32 brake brake actuators , spindles, 12 inch Rocky Mountain brakes.

What year shackles and bushings should I use to get the job done?

What is the inner diameter measurement of the A spring?
What is the inner diameter measurement of the 32 spring perch?
What is the outer diameter of the 32 verses 31 shackle bolt?

As always guys thank you so much for your help.

 

[gwhite]

'32 perch is 3/4" ID
A shackle is 9/16"

You need a spacer (bushing) 3/4" OD x 9/16" ID - 1 3/4" long to go inside your 32 perches. Then use the A shackles. McMaster-Carr sells bronze bushings in that size x 3" long - trim to fit.

 

[gwhite]

McMaster-Carr part #6381K5

 

[skryla]

Just an update:

Here's my parts list to put a '32 axle and brakes under a '31 - about a 3.5" to 4" drop.

'32 Axle
'32 Spindles
'32 perches
'32 Rocky Mount brakes
Flat head Ted brake floating system
'31 shackles
'31 king pins
'31 brake actuators
'31 brake rods
'31 spring, reverse eyes and remove 2 leaves, move main 1 up in pack.
'31 drag link
'31 wishbone
'31 tie rod
'31 pitman arm

Also needed (thanks Gary) You need a spacer (bushing) 3/4" OD x 9/16" ID - 1 3/4" long to go inside your 32 perches. Then use the A shackles. McMaster-Carr sells bronze bushings in that size x 3" long - trim to fit.McMaster-Carr part #6381K5

Also put a Model T spring with reverse eyes in the rear, about the same drop. Rear conversion (from Ebay - Pure Hot Rods and Kenny's Shocks)

Not happy with the '31 box, going with a Mel Gross F100 box. I'll let you know how it turns out.

Brakes are very good. Can lock them up if I want to.

Thanks to TJ of Throttle Jockey Originals of Long Island for his help with final assembly and fabrication.

 

[gwhite]

Great to see the update!

Rather than the F100 steering box, have you considered a 33-4 box? They mate up perfectly to the A sector housing (33-4 shaft, worm, box, sector, A sector housing). I'm using one in my T RPU on an A chassis.

 

[skryla]

Great to see the update!

Rather than the F100 steering box, have you considered a 33-4 box? They mate up perfectly to the A sector housing (33-4 shaft, worm, box, sector, A sector housing). I'm using one in my T RPU on an A chassis.

I had looked into the later box. The Gross box kept coming up on threads with good reviews.

 

[PeteVS]

What are you using for rear shocks? And, do you have the same picture of the rear shock taken with flash to get a bit more detail of the upper mount? Thanks!

 

[Barry B./ Ma.]

What are you using for rear shocks? And, do you have the same picture of the rear shock taken with flash to get a bit more detail of the upper mount? Thanks!

If it's like mine it bolts directly to the rear crossmember, they included in the kit a template to locate the hole location, easy drilling, either a 7/16 or 1/2" hole. I figure if the shocks didn't work out the holes could be welded. The shocks work very well by the way.

 

[d.j. moordigian]

skryla,

I have three 32 front axles. My Model A front wishbones don't fit
any of the axles,...the perch bolt holes seam to be farther apart
on the 32's than the A's. Maybe 1/2" to 3/4" at most. How did you
correct for this?
Also, did you correct for caster?

Thanks, Dudley

 

[Tom Foster]

I have a dumb question about something that's bothered me for a while. If you reverse the spring eyes, how do you use a spring spreader to mount it?

 

[gwhite]

skryla,

I have three 32 front axles. My Model A front wishbones don't fit
any of the axles,...the perch bolt holes seam to be farther apart
on the 32's than the A's. Maybe 1/2" to 3/4" at most. How did you
correct for this?
Also, did you correct for caster?

Thanks, Dudley

You have to use a spacer between the axle and wishbone.

Caster is set by the front x-member, no need to correct it.

 

[d.j. moordigian]

You have to use a spacer between the axle and wishbone.
I have no problem, needing a spacer,...the perch bolt spread is
different between the "A" wishbone and the "B" axle.

When you lower the front end, by an axle, you loose caster! The
only way I cansee too correct for more caster is too take a thin slice in the
wishbone(then reweld) to kick the axle, for more caster.
Caster is set by the front x-member, no need to correct it.

Thanks...

 

[gwhite]

You've got it backwards, caster is increased as the axle gets closer to the x-member. The additional inch of drop from reversing the eyes of the spring may add 1* or so...probably not enough to notice under most circumstances.

Swapping to a 32-6 axle should have zero affect on caster.

 

[d.j. moordigian]

You've got it backwards, caster is increased as the axle gets closer to the x-member. The additional inch of drop from reversing the eyes of the spring may add 1* or so...probably not enough to notice under most circumstances.

Swapping to a 32-6 axle should have zero affect on caster.

Tire diameter(and height) changes the caster, the small, less caster.

As you stated in # 11, "the front cross member sets the caster",
correct?
When the frame, in the front, gets closer too the ground, the front
cross member gets closer too 90°,...loosing caster.
But I will check it when I get to that part of the project..

 

[gwhite]

D.j., think of the front axle (when viewed from the side) as swinging on an arc...the center of the arc (pivot point) is the radius rod ball. As the axle moves along this arc, fixed at the pivot point by the radius ball, caster increases (the top of the kingpin angles toward the rear of the vehicle) as the axle nears the cross member and caster decreases as the axle swings down along its arc away from the cross member.

Will see if I can come up with a drawing to illustrate this.

And I should also revise my previous statement... caster is set by both cross member AND radius ball position. Caster is unaffected by tire diameter, trail, on the other hand, changes with tire diameter; smaller tire, less trail - larger tire, more trail.

 

[1931 flamingo]

Just curious as to why this swap?? Is it for better braking?? Is it to lower the front??

Paul in CT

 

[d.j. moordigian]

Just curious as to why this swap?? Is it for better braking?? Is it to lower the front??

Paul in CT

Hi Paul,

I've collected, in the past 45+ years, a bunch of spare parts, including
enough cab parts to build a 28 CCPU. I always wanted a 1928 CCPU.
So I have a hopped up "B" engine, a 32 "heave" front axle and
a V/8 Halibrand quickchange rear end. Also a V/8 top loader transmission.
It's kind of a bucket list, thing...

Yes, the stock 32 front axle is about a 1" drop over an A axle..

 

[d.j. moordigian]

gwhite,

Yes, please do a drawing....

 

[Fordors]

D.j., think of the front axle (when viewed from the side) as swinging on an arc...the center of the arc (pivot point) is the radius rod ball. As the axle moves along this arc, fixed at the pivot point by the radius ball, caster increases (the top of the kingpin angles toward the rear of the vehicle) as the axle nears the cross member and caster decreases as the axle swings down along its arc away from the cross member.

Will see if I can come up with a drawing to illustrate this.

And I should also revise my previous statement... caster is set by both cross member AND radius ball position. Caster is unaffected by tire diameter, trail, on the other hand, changes with tire diameter; smaller tire, less trail - larger tire, more trail.

There has to be some loss of caster when using a smaller front tire, or a larger rear tire, and an even greater loss when using big and little's as is common on hop ups. If the frame were level and wishbone ball height and front cross member were engineered to provide 5° caster on a stock vehicle any change will affect the caster; simply put, the change in ride attitude with a lower front end will pitch the front cross member forward resulting in less caster.
Tire sizes, dropped axles, installing a Model A rear spring on an early V8 to clear a quick change are just some of the things that will bring about a change in caster.

 

[d.j. moordigian]

There has to be some loss of caster when using a smaller front tire, or a larger rear tire, and an even greater loss when using big and little's as is common on hop ups. If the frame were level and wishbone ball height and front cross member were engineered to provide 5° caster on a stock vehicle any change will affect the caster; simply put, the change in ride attitude with a lower front end will pitch the front cross member forward resulting in less caster.
Tire sizes, dropped axles, installing a Model A rear spring on an early V8 to clear a quick change are just some of the things that will bring about a change in caster.

Ahhhhh!..........that's why I asked the question! I wanted to know
what the rest of the "group" was doing. Tho I know how I'm going
to do it!

Thanks..