suspension for a 31 Model A on a 32 frame with quick change rear

Hi guys,
I am building a 31 Model A on a 32 frame with a high boy stance.
The body is is channeled about 1" but want to have the frame/suspension somewhat low but nothing crazy.
I have just ordered a new winters V8 quick change for the car, I am running the buggy springs front and back but my after market frame was set up for coil overs.
I have also have a set of the 36 trailing arms that have the spring mounts on them.
I had purchased a new 40 spring since I was going the 9" route, but now with a quick change I believe I have to buy a Model A style spring.

I am looking for any advice on this setup such as spring crossmember, spring size, any issues with 36 trailing arms and a model A spring setup
Basicly if you see me heading toward any pit falls, please let me know
I am completely new to early hot rods after playing with muscle car stuff for the last 35 years

I do have the orig model A frame that I might be able to use the rear spring crossmember but wasn't sure if round or square tubing would be a better choice. The frame has round tube now for the rear coil over setup

Thanks
Dave

 

Rear A crossmember and spring, use a torque tube driveline or a torque arm with those radius rods, they are not meant for keeping the rear axle from wrapping. Guys have done it no problem, how much of it was luck is the question.

 

Thanks pocket! Was thinking of maybe cutting up the model a rods for a 4 link style setup, maybe even the front suspensions rods since they look a little stronger

 

So should I set the 36 rear radius Rods at the same width the model A mounts were?

 

The perches need to be parallel to each other and perch hole center to center using a model a rear spring is 49", that is the determining factor on placement. When you go to put the spring in it has to be stretched to fit so it has a pre-load in it with out the weight of the car on it. That last part is dangerous and someone who has done it should be called in.

 

Consider a 'T' rear spring. Many posts on this subject, by many who had to change (from too tall 'A' spring!)

A tool for safe spreading of the spring can be made from a 30" length of Allthread, (1" diameter) and a 20" length of 1" galvanized pipe.
Flatten the spring eye end of the pipe, so it 'locks in'...grind the end of the Allthread at a 45* angle to wedge into the end of the rolled 'eye', next the main leaf. A nut on the Allthread will adjust the length, stretching the spring to the specs of hanger placement.
I dare say finding a 'seasoned expert' may take endless visits to a series of rest homes...but senility has its merits! (don't trust anyone under 70!)

 

Ok thanks, I have seen the spring tools for spreading them. I figuired I maybe heating and bending the radius rods to work but we will see

The model T spring seems interesting I will try and dig up some topics on it!

 

It's amazing what many "older gents" remember about the good ole days! lol

 

Considering you have some pieces I'd use what you have. The 36 bones, 40 spring and build a flat crossmember or stand off spring perch for the 40 spring. That will get you as low as you can go and the least effect on your floor pans.
The Wizzard

 

Yes that was the plan but the quick change is going to be in the way, I need a high arch spring for clearance

 

Oh wait, I missed the Quick Change. You need a T or A rear spring. Here is a photo for Food for thought. Notice the frame to Axle spacing. That is just the Main leaf in place. Once the complete spring pack is there it lifts about 2-1/2". 3" is plenty travel. You don't need a spring spreader. Just place the main leaf in place and a long piece of All Thread to put the spring back together.

The Wizzard

 

I've got the same set-up but with a 32 coupe. 36 bones, Halibrand Champ QC (same size as a Winters) Model A rear member with a Model A spring. Had to do some major surgery on the trunk floor to suit the Model A member, shock mounts and the QC. With your channel you may have to raise your floor to suit and definitely to clear the QC. Is your chassis C'd over the axles. Mine is and with a full spring pack I've just got enough chassis/axle clearance. I do have reversed spring eyes which gets you an inch or so lower.

 

Ok thanks pist-n-broke will try the all thread

Swifty, my frame is c'd also. I have no trunk floor yet just the rear trunk panel tacked in a few spots that is for the trunk latch. I am sure it's going to need some loving to put the spring mount in.
Could you post a picture of your car so I could see the stance, it would be greatly appreciated!
Thanks
Dave

 

Dave, started a conversation with you.

 

Some good reading for others doing this

http://www.jalopyjournal.com/forum/threads/need-help-on-rear-buggy-spring-model-a.689722/

 

36 bones are perfect if you add a third link as a torque link. You will have to extend/stretch the frame 7 1/2 inches to keep the same wheel base when you switch to spring behind setup. That is the distance from the center of the axle to the center of the spring mounts on the 36 bones. A model a spring and rear crossmember will work well, unless you want to go really low. I've got pictures somewhere of that exact setup somewhere, I'll see if I can find them. Turning 36 bones into 4 links is a waste of bones, as you will really just be reducing them to sections of tubing, as they would need a pivot/bushing at the axle tube, making the forged mount useless.

 

badshifter, I did not refer to my rear suspension correctly, a 4 link would be much differant than what I had in mind.
What I was really thinking was adding 2 model A radius rods that pivited on the frame at the same point as the 36 rods or "bones" I would probably just attach with this and just a simple plate with a hole that would be welded to the top of the 36 rod
probably the same on the other end at the top of the rear ends axle tubes.
Kind of like a big ladder bar, does that make better sence?

 

Sorry for the gigantic picture

 

Did a customer chassis some time ago with 36 bones but used the narrow (44 inch) Posie A spring to narrow up the mounting points for the 36 bones on the rear axle which helped minimize the interference with the bones to the frame rails which can occur with the wider (48 inch) mounting points. Mounted the front with a P&J ladder bar cross member and P&J 5/8 th adjustable ends. Also built a single torque arm similar to what Hot Rod Works offers. Everything seems to work good.

 

Thanks for the pic bad shift that seams simple enough!

Krylon32 that 44 inch spring sounds like a great option!

 

LOL torque arms are over rated.

I am not sure that it is a matter of luck, it is more a matter of getting radius rods that are not rusted thin from age, not throwing much meat at them and not hooking up. Somewhere there is a pic floating around from when the raven first decided to go with slicks on the roadster, we already had the radius rods beefed up and they are still arched to the point of looking like a rainbow. A torque arm is a good idea with modern tires and HP/Torque.


@rsss396 I just happen to have an A spring and would use a 40 spring if I had one. Shipping would be the only killer to the deal but maybe we can make it work of someone is traveling this way.

 

Yes I do not trust just the 36 radius rods for sure that's why I was thinking of the 2 upper radius rods that would tie in with the lower 36 rods.
Not sure if that is better than a torque arm or not. I have 1" threaded shank heim joints with 3/4" hole in the ball that I thought I would thread into a 1" female couple welded on the end of the 36 rod. Should be strong enough and have some articulation with the rods angled back as close to the drive shaft area as possible

I have a complete model a chassis with a spring but think I like a narrower model A or T spring but thanks for the offer porknbeaner

 

I think I have a narrowed A rear spring at the shop. I'll check in the morning. If I remember right, it's also reversed.

 

Ok thanks bad shift!

 

has anyone tried the Speedway "Medium Arch Transverse Rear Leaf Spring, Reverse Eye, 38 Inch"
http://www.speedwaymotors.com/Medium-Arch-Transverse-Rear-Leaf-Spring-Reverse-Eye-38-Inch,43786.html

 

After reading the negative reviews on the 38" from a few on speedway stating it was not heavy enough to support a Model A, I decided on the posies super slide spring which is reversed and 2 inches narrower. So we will see how it works out
http://www.speedwaymotors.com/Posie...ed-Rear-Leaf-Spring-28-31-Model-A,118701.html

 

moparob is using that spring if im not mistaken http://www.jalopyjournal.com/forum/...-coupe-underslung.875038/page-4#post-11357217

 

Sorry if its not too late, I have a reversed model A Spring that is 40 1/4" center to center. It's an original spring I had Atlas Spring narrow and roll. Never used it. PM If you can use it.

 

This is how krylon 32 built mine; worked out great.

 

Bad shift I ordered one from speedway but thank you
Car doc your setup looks great!