Leaf spring advancements

Has anybody thought about changing out the rear segment on a Calvert mono leaf for more or less stored energy ..
has anybody ever mixed a composite rear segment with a steel front segment
I'm currently working on changing things around looking for more stored energy however the Calvert Springs just do not have very much Arch definitely not as much Arch as I would like.. the rear end currently suspends 3 inches from ride height before the car has to fight the spring as well as the shock I'd like to increase that to 5 in of free travel and maintain a relatively low stance

Calvert will make any arch you want. I would call them and discuss it with them.

Not anymore the business has sold I just don't think they have the technical background anymore

Landrum does leaf springs. Haven't talked to anyone at Calvert. Someone should be able to build a spring to spec.

Spring rate and compression at ride height. I'm not an expert but a low rate spring with enough arch to get it loaded and hold desired ride height will store more energy than a high rate spring that is deflected less..

More horsepower, gear, etc usually means less help needed from low rate springs to get the tire applied. i.e same car, same weight with a mild small block and automatic would get a different spring than a decent big block stick combo. Springs matter. They don't just hold the car up as some people think.

You would need a weaker back half with more arch. Just not sure who would make it. Rhodes, Barnett, etc have been so quick they are most likely using a stiffer back half. Maybe thining the section width wise to weaken it? And then moving the slider mount towards the ground to maintain ride height?
Doug

Seems to me the guys with a particular X275 '68 Dart ran them and had a record of 4.17 in the 1/8th at the time. So I know it can be done. The latest thing is to put Caltrac Sliders on them. I am considering this for mine. And yes, mine are relatively flat as well. But I bet my 1.33 sixty foot is nowhere nears yours. I am not happy with the ride they give, or the inconsistent 60fts.....I actually like the RMS rear bolt on 4-link system even more...Wondering if that could be adapted to my tubbed POS...I would call Calvert and get one of their techs on the line....

My thinking here is a power Adder car has enough horsepower to separate the spring Beyond its neutral position down track on a motor car we lack down track horsepower which means the leaf spring is actually trying to pull the tire back up off the track.. this is just a theory for instance I have five and a half inches of shock travel and a leaf spring that only suspends two and a half inches from ride height.. so the car on separation actually is beginning to fight the leaf spring after two and a half inches I think ideally when I'm looking for is for the same right height and a leaf spring that will suspend five or six inches that way all of the action will be controlled by shock adjustment not the added variable of the spring

. You're thinking exactly the same way I am I'm just trying to figure out the best way to get there

Maybe try a section from a stock leaf spring and cut it to be a rear section?

Exactly, the more power you have the less help you need with planting the tire. So without a poer adder, you want a spring with less rate. To acomplish the same ride height with leafs there are 2 options. #1 mount the spring attaching points lower in the body. Since your instant center seems to be working that means moving the rear slider. #2 find a spring segment with more arch. There are probay more places that could built a steel spring then there are a composite. The trick is knowing what rate you need. Any arch could be put into a steel spring.

Do you know the current spring rate?

So maybe its time to call your shock guy. Most of the fast leaf spring cars are using the blue Afco's or Santuff shocks...I know the valving is key...

https://www.afcoracing.com/store.aspx?itemid=3548&pagetitle=Big-Gun

Rhodes makes it seem simple:
https://www.motortrend.com/features/leaf-spring-tips-tricks-x275-racer-ron-rhodes/

Would this give you what you're looking for?

https://www.lpracing.net/product-page/rear-leaf-spring-separation-sliders

just add a small plate kit .....


I know...... LMAO , im just being "that guy"

Props for keeping it all motor

The level your at now......info doesnt seem to come easy .
As already mentioned, get with a "good" shock guy and hopefully you get some help. ALSO 235 radial cars are right at your ET level, and yes they have a power adder but some are leaf spring cars and maybe some of that info can crossover to your program.
Are you data logging, and do you have rear shock sensors to see the travel as the car is going down the track??

AND ....nitrous cars dont add power down track, usually the kit is all in by .9 or less , so in reality you are pretty close to a 235 radial car

DA shocks to control it all.

Maybe some fancy shocks to hold the housing out until you want them to release.

With some of the stuff I'm involved with now, I'm getting into OEM suspension stuff more than I have in the past. Same principles apply.

A spring - coil, leaf, torsion - all react the same to a change in rate and preload/compression at ride height.

Shiloh,

Not sure where you heard that Cavert has sold but apparently it is not true.

I asked the company about it and this was their response:

"No sir, not true at all, John Calvert is still owner, he did move to
Arizona a year ago, so maybe that is why someone thinks this."

I have not used their customer service lately so I can't comment, it used to be excellent.

Bill

My theory is as stiff as possible on the front segment and soft on the rear. Kind of mimic what a ladder bar does with the front being stiff and the rear having the springs that hold up the car. All the rear segment would do is technically hold the car up.

I've wondered about using tubing for the front segment and the rear section from a calvert spring. It would eliminate the need for any type traction bar............I think.

yeah working closely with mensker there shocks are on all four corners and have been back and forth a few times to tune them up.. yes we have racpak unfortunately we do not have travel sensors at this time however we do video under car often typically the problem is at the area that we want to work on is .3 to .4 typically. And I do agree with your statement regarding the 235 tire stuff. on a good track like Vegas or Sacramento a 1.12. 60 ft is common on the marginal tracks where I think we can be better.

I have been an advocate for Calvert for many years it has been noticed that there has been a change I guess

200 lb

. One current thought is to mix in a set of composite Landrum on the back half which I can get in 175 lb spring rate which is a little lighter then what we currently have not to mention gets rid of quite a bit of weight

There were a few 235 cars in the 90’s at Lights out. Was fun being down there watching them
Stef, who many on here know , was down there with his son and his 235 Duster with gen3 power. Brand new motor, they were in the mid teens with 1.15 60 foot leaving at 30% this in 85 degree heat. On Leafs, about 75 pounds to heavy
Not sure if it was Bradenton or Orlando but somebody went 4.65. I understand it’s an “ outlaw” car, not sure what isn’t legal on it, or who it was.

Not like you’re bound by rules! Back half time!

The car you speak of going 4.60's on a 235 , yes that is a Fox body with a Turbo BB chevy based engine, Its not follwing the 235 class rules. So really not a fair comparison that car can run 4 teens on a 275

Those 235 guys are impressive, to me at least. 5.0's with a n/a small block is more impressive though!

I see both side's of the story, if you want to go fast i would go with the mono-leaf, I am building a car like i was #16 years old, that is why i moved in the spring #3 inches, with the super-stock spring, it was around then. that is a good point !

They legged it out on the last day of Sick Week to go 7.1X@206 or something dumb on a 235 tire lol.

As Dragula said, get the calver sliders, they are made at an angle & will give you more axle drop, or something like these ???

I did purchase a set of those just not sure I want to go to that

So you could calculate from that.
How many inch's do they compress at ride height?
What's the front and rear spring segment lengths?

Aluminum caltrac upgrade

Hollow 7075 saved a few ounces on each side

Sweet! Just as long as it can handle the stress they see at launch and not flex or bend. I bet its is pretty high.

The Khouty boy's were having consistancy issues last year with their all motor car. Vince senior told them to take out the titainium 4 link bars and replace them with steel. It fixed the issue.
Doug

these are made out of 7075 which technically is stronger than the material that was originally used I have ran them for two events now with great success I can't say there was any Improvement but the car definitely went straight every pass

I would get some LP racing rear leaf spring brackets, if your sticking radial, and a set of shock sensors. Do you run an ARB in the back?

I have the second set he ever made however I haven't installed them yet no I do not run an ARB