Belltech Drop Leaf Spring Rate? Reply with quote Edit/Delete this post Delete this post View IP address of poster
Anyone know what the actual spring rate is on the Belltech 3" drop leafs? I'm debating whether or not I should have a custom main-leaf made for these to raise the spring rate to what I want, have a custom rear eye made (I want to run Johnny Joints front and rear) and a torque/traction leaf added or just run the off-the-shelf springs. Thanks.
FYI I was quoted ~$60 per side for new main leafs IIRC, and $35 per side for traction leafs (this is a half leaf that goes from the axle perch to the front spring eye and actually wraps around the front eye for increased anti-wheel hop without increasing spring-rate) from Alcan Spring. If you have a set of stockers lying around, it might be a good option for a semi-custom rear spring.
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greencactus3
hmmm thats something ive been considering for a long time. cutting a leaf in half and just using the front side, or just the rear half...(and clamping it to the main leaf)
but i didnt quite understand which would be more beneficial...
also whether above the main leaf or below the main leaf.... didnt want it to mess the pinion angle either...
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hardline_42
greencactus3 wrote:
hmmm thats something ive been considering for a long time. cutting a leaf in half and just using the front side, or just the rear half...(and clamping it to the main leaf)
but i didnt quite understand which would be more beneficial...
also whether above the main leaf or below the main leaf.... didnt want it to mess the pinion angle either...
Green, the benefits of a torque leaf are that it acts like a traction device like caltracs or slide-a-links without the negative aspects like poor handling and reduced ground clearance. A torque leaf actually wraps around the front spring eye like this (the glowing leaf):
You basically end up with a very beefy spring that has built-in anti-wrap characteristics without adding spring rate, all in a package that doesn't take up much more room than stock. The extra leaf always goes above the spring pack and towards the front so that as the axle tries to wrap up, the leaf pulls it down, cancelling it out. Also, you would only be lowering the truck by the thickness of the extra leaf, as if it were a really thin lowering block, so the typical means of correcting pinion angle apply (ie. shims).
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s10cyncrvr
I have the formula out of Herb Adam's book to calculate spring rate of a leafspring. I also have a set of leafs I can measure. I'm just not sure how accurate it will be. I'll see what it works out to tomorrow.
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hardline_42
s10cyncrvr wrote:
I have the formula out of Herb Adam's book to calculate spring rate of a leafspring. I also have a set of leafs I can measure. I'm just not sure how accurate it will be. I'll see what it works out to tomorrow.
Thanks, I look forward to it. I have to dust off Chassis Engineering and take another look at it myself! I just didn't want to spend the money on a set of Belltechs if the rate isn't what I wanted so I'd appreciate it. Thanks again.
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s10cyncrvr
I took the measurements this morning. The width of the leafs is 2.5". There are 3 leafs bundled together. The thickenss of the leafs are 5/16". The length of the spring is 53-3/4". Using the formula, it came out to 122.
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hardline_42
s10cyncrvr wrote:
I took the measurements this morning. The width of the leafs is 2.5". There are 3 leafs bundled together. The thickenss of the leafs are 5/16". The length of the spring is 53-3/4". Using the formula, it came out to 122.
Thanks. That's pretty low. I was hoping for something closer to 175-200. I might have to see if I can find a cheap used set of Belltechs and have them modified or spend some money and get a set of Flex-a-form fiberglass leafs with some Deaver Baja Bushings. There doesn't seem to be much selection for these truck when it comes to springs.
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greencactus3
back to the torque leaf... what kind of arch is on it? is it matched to the main leaf at droop? or at ride height?
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hardline_42
greencactus3 wrote:
back to the torque leaf... what kind of arch is on it? is it matched to the main leaf at droop? or at ride height?
The torque leaf is a part of the spring pack so it conforms to the arch of the adjacent springs. It just doesn't go past the spring perch so it isn't a complete "arch" and doesn't add to the total spring rate in the way that an overload or add-a-leaf would. Anything you can do to stiffen the front of the spring reduces wrap-up. A lot of performance spring manufacturers have the second and third leafs extending a lot further towards the front eye to stiffen this area. A torque leaf takes it a step further since it's dedicated to reduce spring wrap.
