Technical 1-3/4 leafs and axle wrap.

Im putting together a 52 210 straight axle car. Trying to get it running before the tracks open in spring. And I know I know, people are tired of "budget build threads" but reality is reality and Im trying to get it done on the non expensive side. Or at least spreading the money out because the car needs a lot.

My question is are the stock style skinny leaf springs considerably more susceptible to axle wrap issues compared to the later and more common 2.5" wide leaf springs used in Gm cars forever. You can put traction bars on the 2.5s and reasonably keep them in check, can you do the same for the skinny springs?

I would rather spend money elsewhere that needs it, but Im going with the old realizable and affordable Explorer 8.8, and don't want to have to weld on perches twice. So if I stick with the 1.75" springs they are likely on there for a while.

 

Traction bars, also known as slapper bars, don't care how wide the spring is.

They still work the same way.

 

Fair enough.

 

Double stacking a main leaf with ends cut off is an option.

 

homemade Cal Tracs would help, and offer an adjustment option too.

 

45 year old springs have bent up and down a bunch in that time. Just something to think about!

 

Experiment with clamping the front of the springs. Sometimes it works sometimes not.

 

You got to ask yourself if you want to pinch pennies in that area or spend a little more once and be done. Plenty of leaf spring gassers running floaters and ladder bars, ladder bars plant the tires and the springs only hold up the body.
What's your ultimate goal here, continually going faster ? You have to get the bones of the build right for your intended purposes, sometimes the weak link can ultimately destroy all of your hard work, I broke an axle that put me into the guardrail, the cost of the repairs far outweighed the cost of those new axles I should've bought.

 

That doesn't matter............Springs never lose their stiffness [unless some DIY metallurgist attacks them with heat]
Over millions of cycles a spring will lose it's set [or if it is bent beyond the point of yield it will re-set]

A re-set 45 year old spring is just as good as a new spring [with the same specs]

It is forward thrust [not pinion torque reaction] that causes axle tramping[wrap]
The point of thrust is at the axle centreline . The point of "resistance" is below the centerline at the spring pad.
So in a perfect world the pinion will try to "nose down", but in reality the combination of thrust trying to shorten the spring AND added pinion torque reaction causes the spring to "S" shape itself.
[The tramping is the kinetic energy being released from the springs]

Adding a 1/2 leaf will help this effect, or a simple link that transfers thrust from the rearend into the frame [which is how a Caltrac works]
A traction override bar [used in early Shelby Mustangs] is better at controlling brake torque. But to be more effective in drag racing ,it really needs an extra 1/2 leaf making it a pseudo 4-link.

 

Those are the questions Im asking myself, again, I flat out cant get it all perfect this season. So Im trying to apply the dollars to fix holes that must be fixed. Where is it safe to put it off for another day etc.

Its not going to have a ton of engine to start with, so yes the point is to continually upgrade.

 

I learned this lesson years ago , 37 Coupe . I twisted up a NOS set of springs into an S shape rather fast . Remember the torque tube is designed , just as how it is defined . A TORQUE TUBE , it was to keep the springs from wrapping up . I built a set of traction bars as suggested , and never had one more issue . When building the bars remember the frame is only made of nothing more than folded sheet metal . Give some real engineering thoughts , when anchoring them to the frame .

 

Slapper bars are an effective way to control spring wrap without negativity affecting the ride. I built some for my 401 nailhead powered ‘50 Sedan Delivery after finding out that on hard acceleration the rear was twisting so much that the yoke was rubbing the floor pan.
On my ‘38 409 powered Gasser I built some ladder bars and attached the rear axle to the original springs with home made sliders.

 

A buddy and myself put together a 73 Capri (built 400 sbc etc) YEARS ago.
It too had narrow leaves and we ran basic slapper bars at first.
The rear tires were 1 1/2" from the end of the rocker panels at rest, but something didn't feel right under hard acceleration.
Come to discover the paint was completely polished off both rocker ends by the tires.
Thats how much the springs were deflecting!
I fixed it with a homebuilt ladder bar setup and a conversion to coil springs.

I imagine you could easily make some old fashion "lift bars" that tie the rear axle to the chassis farther up towards the front, to give an old school look to the car, instead of going the somewhat modern full ladder bar or 4 link route.

 

This is what we used for my 31' Roadster. They work pretty good.

 

Is there a brand/part number for that? Or did you just put on some tie rod ends to a threaded rod?

 

You've said you have a 52. What body style is it?

 

It was made from Tie Rod parts..

Sent from my SM-G950U using The H.A.M.B. mobile app

 

Its a styleline, two door. Now Im a bit confused on the coupe/sedan thing. With other cars its a full window frame or door pillar, but I m not sure on this early chevy. Im not even sure there is such a split, but I believe ive seen parts advertised as for a 1952 sedan and wondered if there was a two door sedan.

 

It looks like a 51 coupe. It has 51 trim. It's hard to see with out a good profile picture if it's a sedan or coupe.

 

.

 

Thank you for that, Im still having a hard time seeing the difference. The rear quarter window is a little bigger?

And maybe its a 51 and Im mis remembering. I havent looked at the title in a minute. To me its just a race car lol. I havent dove into the minute details or trim differences like I would on some other of my projects. This one is, drop a BBC in and try to do a wheelie.

 

Cal trac

 

Sure about that ? maybe weaken some? Arch? Bend? Not agreeing with your statement there.......
But- Go with those thoughts,and run them. Just don't try to tell anyone different...........

 

I'll put money on that it's a sedan. Rear side window looks a little larger than a coupe. If, the window rolls down, game over, it's a sedan.

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It is a '51 2 door sedan. A coupe has a shorter 1/4 window.

Ray

 

Read my whole statement.

Arching or Bending is basically changing it's setting.
If you clamped a spring for ?[10+years?] it will reset it's load height, but it's linear rating won't change [lb/in]

This even applies to valve springs. If an engine isn't started for a while, the valves that were left open will reset , so the seat pressure changes [but the stiffness remains constant]
Shimming the springs will restore the seat pressure but the spring height gets closer to coil bind when open.

 

No- Cycling for upteen years, and or setting, is going to have an impact.
Valve springs? Same applies..... Those at rest, those in bind...... = Shims to those in bind? who does that these days?
I know how springs work......on a rear end,on a head, or even a throttle return spring,,,,,,,,,,
Sorry man- aint buying your logic.............
Run those thoughts on your own ride,but don't post up here for the uninformed to believe.

 

METALLURGIST NEEDED ON POST#29! Stat!

 

I run original traction masters on the car in my avatar it has narrow springs no wheel and it leaves hard with one wheel off the ground . The traction master co. is still in bis in la.

 

I’ve been on their site before. They don’t currently list a Chevrolet earlier than the 55-57.