custom ttb springs

[swynx]

after trying to get information on skyjackers 2 inch leveling coils (132x) and not finding anything, i dont know if they are the coils i want.

ive read srsblewis thread on his custom front lift

http://www.therangerstation.com/forums/showthread.php?t=109684

seems to have worked really well for him, im trying to avoid buying all the additional parts he used by possibly having a custom coil spring made.

he used f150 part cc810 with 270 ppi 13 inch install height, and 17 inch free length, variable rate.

does 13/17 with 300 ppi sound about right for 2 inch lift with a supercab? (extra 300 ppi for the super cab/winch.) variable rate or no?

truck only see's road time on the way to the hills. it is not a daily driver.

 

[swynx]

so i was quoted over 500$ with shipping and handling for custom springs. any one know what the tallest coil you can fit without stock ttb brackets is? i feel that 270 will be a bit short.

the bronco graveyard has 320 ppi coils, but there 18.5 inches unloaded and 13 inches loaded, they have the same loaded height of the cc810 springs, but are 60 ppi higher and 1.5 inch taller.. i have a winch with steel cable (100 lbs) but i dont know if it will offset it enough to get aligned.

 

[4x4junkie]

What you'll need to do is accurately weigh the front of the truck and then subtract for the weight of the wheels/tires and part of that of the axle (usually around ~300 lbs, give/take a little depending on your tire's size). Then calculate whether the spring will compress to where you want it.

Say for example a scale shows your truck as weighing 2400lbs on the front axle (a stock Supercab V6 4WD should be around 2200-2300)... That's approximately 2100lbs the springs are supporting.
The TTB axle also has a "nutcracker" effect of approximately 1.5:1 against the springs, so in reality it's actually 3150 lbs against the springs.
Divide that by two and it's 1575 each side.

If the compressed height you need them to be at is 13", then a 320PPI 18.5" coil looks like it would come pretty close for a front weight of 2400lbs (close enough you should be able to align it via the camber/caster bushings).

2400lbs - 300 ÷ 2 × 1.5 = 1575 (weight each coil will support)

1575 ÷ 320 (PPI) = 4.92 (amount the coil will be compressed)

18.5 - 4.92 = 13.58 (compressed height the coil will sit at)

 

[swynx]

thats good to hear, i wasnt sure if that extra inch would be a limited factor or not. next time i go to the junkyard i will weight the weight of the truck.