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Old 10-13-2020, 10:29 PM
ScotI ScotI is online now
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Quote:
Originally Posted by Beechy View Post
ScotI.......some more info is required to compare rates.

Ridetech quotes 1020 but their arm length might be 6".....entirely possible.
We need to know that arm length in order to compare.

Using this calculator......

https://swayaway.com/tech-room/torsi...te-calculator/

you can compare a 6" arm length to 12" arm for the same bar. Simple multiplication.....the short bar is double the rate of the long for the same diameter and same pillow block spacing.

Also if you shorten your BAR LENGTH (and locating pillow blocks closer) to get inside your chassis rails , you're gonna raise the rate massive. Warning....if your bar length is short relative to the amount of BEND in the arms to get out to your 39.3" then the amount of deflection in the ARMS reduces the bar rate and eventually fracture an arm at the pillow block area. Shortening the straight section of bar increases prolly by the square of change.....shorten 1" = 100# change.....shorten 2" = 400# change.

A HOLLOW BAR is only slightly lower in rate compared to a solid bar ..... how much? I don't know but maybe 5 or 10%. Gotta be on Internet somewhere.

My suggestion in this whole subject would be to calculate the wheel rate of a STOCK truck compared to your MODIFIED wheel rate then use the same percentage of factory bar to your desired bar. Don't OVERPOWER your spring/shock combo.
(ignoring sway bar....so just use the dimensions from inner lower pickup point to spring /shock mount, and inner point to tire contact dimension multiplied into spring rate)
Thanks for the feedback & insight.
I have the pivot point to shock/Lower BJ dimensions in my notebook @ work. I used those numbers when determining a starting spring rate for the C/O's & how I arrived @ the 750# springs. I'll follow up on that tomorrow.

All numbers posted were basing the arm length off of the current 1pc bars on hand. The Addco/PB is the only one that really has multiple bends; the others are pretty much just a 'U' bend ( I_____I ). I had to look @ an earlier version of the RideTech MuscleBar (under my dually) to verify it was similar in shape. The bar the listed 1020# spec was for could in fact be different in it's arm length since it is a more recent version (the bar under my dually is from 2014). These should all share an arm length that's fairly close since the C/L of the bars pivot point to end-link are the same.

As noted in my info, all of these C10 bars were wider than the modular set-up I'm considering which is part of the reason I'm searching for a replacement. The closest being the BellTech bar which is @ least 1" wider @ the base/arm).

With the 'standard' width (length) modular bar @ 37.5" plus the heim 'high-angle inserts', I should/would be @ the C/L of the upper link. I figure their straight arms will be used as-is after cutting to req'd length (they're 18"L) & holes drilled.

Last edited by ScotI; 10-13-2020 at 10:35 PM.
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